Base by Base

Wu J-S et al., PNAS - A PNAS study using smFRET and nano-positioning triangulation maps dynamic positioning of the Rpc34 WH2 domain in yeast Pol III elongation complexes and presents a thiol-capping SPAAC labeling strategy to enable selective site-specific fluorophore attachment. Key terms: RNA polymerase III, Rpc34, winged helix, smFRET, bio-orthogonal labeling. Study Highlights:Using smFRET with ALEX and nano-positioning triangulation, the authors show Rpc34 WH2 occupies three discrete positions across the Pol III DNA-binding cleft and dynamically interconverts among them. A bio-orthogonal labeling workflow—azido-UAA incorporation plus SPAAC with thiol-capping—enabled selective labeling in the cysteine-rich complex. Maf1 binding locks WH2 into the upstream/distal state, validating positional assignments, and HMM dwell-time analysis revealed ordered transitions that proceed through the middle state with characteristic lifetimes. These results indicate Rpc34 WH2 engages the elongation complex via transient, weak DNA and protein contacts, with potential roles in bubble stabilization and rapid reinitiation. Conclusion:Rpc34 WH2 is a mobile, multifunctional cleft-associated module that occupies three ordered positions to transiently engage the Pol III elongation complex, and the thiol-capping SPAAC labeling approach provides a robust route for smFRET studies of large native assemblies. Music:Enjoy the music based on this article at the end of the episode. Article title:Dynamic positioning of Rpc34 winged helix in RNA polymerase III elongation complex for its stability with implications for reinitiation First author:Wu J-S Journal:PNAS DOI:10.1073/pnas.2601775123 Reference:Wu J-S, Chang W-H, et al. Dynamic positioning of Rpc34 winged helix in RNA polymerase III elongation complex for its stability with implications for reinitiation. Proc Natl Acad Sci U S A. 2026;123(27):e2601775123. doi:10.1073/pnas.2601775123 License:This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support:Base by Base is independent and ad-free — no sponsors, no paywall. If an episode was worth your time, chip in and keep the papers audited and the original songs coming:❤️ Support monthly: https://buy.stripe.com/cNifZhclVebvagk2JDgEg01☕ One-time donation: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 More at basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/base-by-base-413-rpc34-wh2-pol3-dynamics QC:This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-07-12. QC Scope:- article metadata and core scientific claims from the narration- excludes analogies, intro/outro, and music- transcript coverage: Audited the transcript portions describing Rpc34 WH2 dynamics, labeling strategy, three-state model, Maf1 effects, NPS localization, and rapid reinitiation implications, comparing to the original article.- transcript topics: Rpc34 WH2 dynamics in Pol III elongation complex; smFRET labeling strategy (azido-UAA, SPAAC, MMTS); Maf1 regulation of WH2 mobility; Nano-positioning system (NPS) localization; Three-state model: distal, middle, proximal; Implications for rapid reinitiation and Pol III processivity QC Summary:- factual score: 9/10- metadata score: 10/10- supported core claims: 6- claims flagged for review: 0- metadata checks passed: 4- metadata issues found: 0 Metadata Audited:- article_doi- article_title- article_journal- license...

7/12/26 • 15:24

Scurich N et al., PNAS - A concise breakdown of a PNAS perspective that analyzes forensic proficiency testing practices using the 2023 CTS firearms test as a case study. The authors identify test design and administration flaws—easy items, consensus scoring, handling of inconclusives, nonblind verification, shot‑to‑shot variability, and contextual bias—that undermine claims about examiner accuracy and the utility of reported error rates for courts and laboratories. Key terms: forensic proficiency testing, firearm identification, false positive rate, test design, cognitive bias. Study Highlights:The authors analyze CTS Test 23‑5262 and report a false‑positive rate of about 20% for bullet comparisons, highlighting broader concerns. They identify structural issues in proficiency testing including ceiling effects from easy items, inconsistent scoring of inconclusives, reliance on consensus rather than ground truth, and nonblind verification. The paper argues these features confound examiner performance with test properties, limiting the tests’ ability to estimate operational error rates and inform court decisions. The authors recommend better test design, blind verification, confidence ratings, and use of objective metrics to improve validation and lab practice. Conclusion:Current forensic proficiency testing practices can conceal fundamental weaknesses in examiner performance and test design; systemic, evidence‑based reform is needed to provide courts and laboratories with meaningful estimates of reliability and to reduce risks of wrongful outcomes. Music:Enjoy the music based on this article at the end of the episode. Article title:Assessing the foundations of forensic identification evidence: A critical examination of proficiency test design and results First author:Scurich N Journal:PNAS DOI:10.1073/pnas.2528192123 Reference:Scurich N, Albright TD. Assessing the foundations of forensic identification evidence: A critical examination of proficiency test design and results. PNAS. 2026; Vol.123:e2528192123. doi:10.1073/pnas.2528192123 License:This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support:Base by Base is independent and ad-free — no sponsors, no paywall. If an episode was worth your time, chip in and keep the papers audited and the original songs coming:❤️ Support monthly: https://buy.stripe.com/cNifZhclVebvagk2JDgEg01☕ One-time donation: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 More at basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/fault-lines-forensic-proficiency-testing QC:This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-07-12. QC Scope:- article metadata and core scientific claims from the narration- excludes analogies, intro/outro, and music- transcript coverage: Audited the transcript sections describing CTS proficiency testing (Test 23-5262), the reported false-positive rates, consensus scoring and inconclusives, out-of-class eliminations, shot-to-shot variability and reproducibility, contextual bias and NIBIN leads, nonblind verification, signal detection theory as reform, a- transcript topics: CTS proficiency testing overview and purpose; CTS Test 23-5262 design and ground truth; False-positive rate findings (around 20%; 19.2% excluding item 4; 22% at least one false positive); Consensus scoring and handling of inconclusives; Out-of-class eliminations (Item 4) and associated errors; Class characteristics and reproducibility concerns across tes...

7/12/26 • 28:15

Nihata A et al., PNAS - This PNAS study describes the development of EKV, a humanized dividing cell line that propagates bona fide sporadic CJD (sCJD) prions, and the Human Prion Assay (HPA), a cell-based method that quantifies infectivity with sensitivity comparable to transgenic mouse bioassay while enabling rapid therapeutic screening. Key terms: sCJD, EKV cells, Human Prion Assay, prion infectivity, anti-PrP antibody. Study Highlights:The authors engineered EKV cells by reconstituting CAD5 PrP-knockdown cells with human PrP (V129) and iterative single-cell cloning to enrich prion susceptibility. EKV cells propagate de novo infectious sCJD prions that reproduce strain-specific pathology when transmitted to humanized Tg152c mice. The Human Prion Assay (HPA) using EKV cells quantifies sCJD infectivity across a wide dynamic range with sensitivity comparable to mouse bioassay but in weeks rather than years. Persistently infected iEKV clones can be cured by the anti-PrP monoclonal antibody ICSM18, validating the platform for high-throughput therapeutic screens. Conclusion:EKV cells and the HPA provide a renewable, scalable, and faster alternative to animal bioassays for measuring authentic human sCJD infectivity and for screening and validating anti-prion therapeutics, while retaining strain-specific biological properties. Music:Enjoy the music based on this article at the end of the episode. Article title:A scalable, dividing cell model for the robust propagation and quantification of human sporadic Creutzfeldt–Jakob disease prions First author:Nihata A Journal:PNAS DOI:10.1073/pnas.2600341123 Reference:Nihata A, Collinge J, Linehan J, Brandner S, Mead S, Schmidt C, Rayner MLD, Jat PS, Arora P, et al. A scalable, dividing cell model for the robust propagation and quantification of human sporadic Creutzfeldt–Jakob disease prions. PNAS. 2026;123(27):e2600341123. doi:10.1073/pnas.2600341123. License:This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support:Base by Base is independent and ad-free — no sponsors, no paywall. If an episode was worth your time, chip in and keep the papers audited and the original songs coming:❤️ Support monthly: https://buy.stripe.com/cNifZhclVebvagk2JDgEg01☕ One-time donation: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 More at basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/ekv-human-prion-assay QC:This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-07-09. QC Scope:- article metadata and core scientific claims from the narration- excludes analogies, intro/outro, and music- transcript coverage: Substantive audit focused on EKV cell development and validation, in vitro propagation of human sCJD prions, HPA implementation and benchmarking against mouse bioassay, drug-screening demonstration, and documented limitations (codon 129 mismatch, occult infectivity).- transcript topics: Prion biology and strain concepts (PRNP codon 129 polymorphism); Historical barriers to human prion culture and need for cell-based infectivity assays; Engineering EKV cells: CAD5-KDB3, human PrP V129, mouse signal peptide; Iterative single-cell cloning and enrichment to EKV; Infectivity validation via transmission to Tg152c mice; Development and validation of the Human Prion Assay (HPA) QC Summary:- factual score: 10/10- metadata score: 10/10- supported core claims: 6- claims flagged for review: 0- metadata checks passed: 4-...

7/9/26 • 26:33

Abson KL et al., PNAS - A cross-species synthesis and theory paper showing that simple molecular diversity metrics poorly predict short-term adaptive potential. The authors compiled >2,100 quantitative genetics estimates (evolvability and heritability) across ~193 eukaryotic species and compared them to nucleotide diversity (π) and microsatellite heterozygosity (He). They find nucleotide diversity explains only ~1.1% of interspecific variation in evolvability and that doubling π corresponds to a modest ~11.7% increase in evolvability. Theoretical models indicate this weak relationship is expected when trait variance is shaped by stabilizing selection, mutation rates, and effective population size dynamics. Key terms: nucleotide diversity, evolvability, adaptive potential, conservation genetics, microsatellites. Study Highlights:The authors compiled 2,113 evolvability estimates across 193 eukaryotic species and matched these to measures of nucleotide diversity (π) and microsatellite heterozygosity (He). They found no meaningful association between ln(IA) (evolvability) and ln(π): π explained ~1.1% of interspecific variation and doubling π predicts only an ~11.7% increase in evolvability. Microsatellite and nucleotide diversity were uncorrelated across species, and both molecular measures were weak predictors of quantitative genetic variation. Theoretical mutation–selection–drift models show weak associations are expected under stabilizing selection and when VA depends more on mutation rate and selection than on neutral diversity. Conclusion:Simple, genome-wide molecular diversity metrics (π, He) are poor predictors of short-term adaptive potential (evolvability); conservation assessments should not rely on these alone and should incorporate trait-based or functionally informed genomic data. Music:Enjoy the music based on this article at the end of the episode. Article title:Nucleotide diversity is a poor predictor of short-term adaptive potential First author:Abson KL Journal:PNAS DOI:10.1073/pnas.2536181123 Reference:Abson KL, Zijmers L, Mittell EA, Young EA, Postma E, Eyre-Walker A, Hadfield JD. Nucleotide diversity is a poor predictor of short-term adaptive potential. Proc Natl Acad Sci U S A. 2026;123(27):e2536181123. doi:10.1073/pnas.2536181123 License:This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support:Base by Base is independent and ad-free — no sponsors, no paywall. If an episode was worth your time, chip in and keep the papers audited and the original songs coming:❤️ Support monthly: https://buy.stripe.com/cNifZhclVebvagk2JDgEg01☕ One-time donation: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 More at basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/nucleotide-diversity-poor-predictor-adaptive-potential QC:This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-07-08. QC Scope:- article metadata and core scientific claims from the narration- excludes analogies, intro/outro, and music- transcript coverage: Audited the transcript's coverage of core scientific claims: relationship between π and IA, the π vs He relationship, functional variation (πN/πS), the theoretical basis (stabilizing selection), and conservation implications/policy directions.- transcript topics: Adaptive potential and evolvability (IA) concept; Nucleotide diversity (π) as predictor of evolvability; Microsatellite diversity (He) and its relation to π and IA; Theoretical mutation–selection...

7/8/26 • 21:48

Shin J et al., PNAS - This episode examines a large transcriptome compendium (PRECISE-NP881) that profiles E. coli K-12 MG1655 across 43 carbon substrates. Independent component analysis resolved 137 iModulons, including 25 carbon-catabolism modules that organize substrates into four activity-defined groups tied to growth rate, substrate chemistry, metabolic entry routes, and proteome allocation. The study integrates growth phenotyping, FBA/ME-modeling, targeted knockouts, and reanalysis of a starvation/refeeding time course to connect transcriptional modules to physiological context. Key terms: carbon response, iModulon, Escherichia coli, carbon catabolite repression, transcriptional regulatory network. Study Highlights:The authors assembled PRECISE-NP881 (881 transcriptomes) and used ICA to define 137 iModulons, 25 of which are carbon-catabolism modules whose activities cluster substrates into four groups. Faster-growing sugars showed limited CRP-linked remodeling while slower-growth, non-glycolytic substrates activated CRP-linked, NtrC-1, Propionate, and SgcABCEQX iModulons. Targeted knockouts (e.g., ΔprpC) demonstrated conditional growth defects on Group C/D substrates supporting a role for methylcitrate-mediated propionyl-CoA processing. Proteome-allocation modeling and projection of an independent starvation/refeeding dataset corroborated links between carbon-response modules, growth/stress physiology, and metabolite dynamics. Conclusion:The paper provides a quantitative atlas of carbon-responsive transcriptional states in E. coli, decomposing CCR into separable CRP-linked and substrate-specific modules and linking these modules to growth rate, metabolic context, proteome allocation, and conditional physiological relevance. Music:Enjoy the music based on this article at the end of the episode. Article title:A systems-level atlas of carbon-response transcriptional states in Escherichia coli First author:Shin J Journal:PNAS DOI:10.1073/pnas.2531884123 Reference:Shin J, Son HF, Krishnan J, Hefner Y, Szubin R, Sung J, Patel A, Lou XA, Catoiu EA, Palsson BØ, Zielinski DC. A systems-level atlas of carbon-response transcriptional states in Escherichia coli. PNAS. 2026;123(27):e2531884123. doi:10.1073/pnas.2531884123. License:This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support:Base by Base is independent and ad-free — no sponsors, no paywall. If an episode was worth your time, chip in and keep the papers audited and the original songs coming:❤️ Support monthly: https://buy.stripe.com/cNifZhclVebvagk2JDgEg01☕ One-time donation: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 More at basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/atlas-carbon-response-transcriptional-states-e-coli QC:This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-07-07. QC Scope:- article metadata and core scientific claims from the narration- excludes analogies, intro/outro, and music- transcript coverage: Audited the transcript sections describing PRECISE-NP881 atlas construction ( ICA/iModulons ), four substrate groups (A–D), CRP decomposition into Crp-1/Crp-2/Crp-3, NtrC-1 and Propionate iModulons linked to propionyl-CoA stress, methylcitrate pathway (prpC/astC), SgcABCEQX prophage iModulon, starvation/refeeding dynam- transcript topics: ICA-based iModulon analysis; CRP-linked iModulons decomposition (Crp-1, Crp-2, Crp-3); Four substrate groups (A–D) and growth phenotypes; NtrC-1 and Propiona...

7/7/26 • 27:15

Tsakiria E et al., Proceedings of the National Academy of Sciences (PNAS) - Using Tau knockout mice and the C. elegans PTL-1 deletion, this study shows that loss of wild-type Tau promotes a conserved shift toward mitochondrial fusion, increases respiratory activity, membrane potential and mitophagy, raises ROS, and enhances stress resilience. The adaptive phenotypes depend on mitofusin/FZO-1 and are phenocopied by FZO-1 overexpression. Key terms: Tau protein, mitochondrial fusion, mitofusin (FZO-1), mitophagy, neurodegeneration. Study Highlights:Across mouse and nematode models, Tau/PTL-1 deficiency increased basal and ATP-linked respiration, mitochondrial membrane potential, and ROS while enhancing mitophagy. Loss of Tau shifted mitochondrial morphology toward a pro-fusion state with increased mitofusin (Mfn1/2/FZO-1) localization and reduced Drp1 recruitment. Genetic removal of the mitofusin FZO-1 abolished the enhanced bioenergetics, motility, longevity under stress, and stress resistance, whereas FZO-1 overexpression phenocopied key Tau-loss features. These results identify a conserved, mitofusin-dependent mechanism by which wild-type Tau restrains mitochondrial fusion and functional adaptation. Conclusion:Wild-type Tau acts as a conserved negative regulator of mitochondrial fusion and functional adaptation; its loss triggers FZO-1/mitofusin-dependent mitochondrial remodeling that elevates bioenergetics and stress resilience in a context-dependent manner. Music:Enjoy the music based on this article at the end of the episode. Article title:Tau protein as a regulator of mitochondrial function and dynamics First author:Tsakiria E Journal:Proceedings of the National Academy of Sciences (PNAS) DOI:10.1073/pnas.2521642123 Reference:Tsakiria E., Campos-Marques C., Ferreira I.L., Trougakos I.P., Dioli C., Gianniou D.D., Silva J.M., Skourti K., Roussos A., Samiotaki M., Sotiropoulos I., Palikaras K., et al. Tau protein as a regulator of mitochondrial function and dynamics. Proc Natl Acad Sci U S A. 2026; doi:10.1073/pnas.2521642123. License:This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support:Base by Base is independent and ad-free — no sponsors, no paywall. If an episode was worth your time, chip in and keep the papers audited and the original songs coming:❤️ Support monthly: https://buy.stripe.com/cNifZhclVebvagk2JDgEg01☕ One-time donation: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 More at basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/tau-mitochondrial-fusion-episode-408 QC:This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-07-06. QC Scope:- article metadata and core scientific claims from the narration- excludes analogies, intro/outro, and music- transcript coverage: Substantively audited sections covering: WT Tau localization and baseline role; Tau/PTL-1 deficiency effects on respiration and mitophagy; pro-fusion shift and changes in fission/fusion proteins; ROS dynamics and hormetic effects; dependency on FZO-1 and rescue via FZO-1 overexpression; implications for Tau-lowering th- transcript topics: Tau deficiency and mitochondrial respiration (Seahorse data in Tau-KO mice and PTL-1 KO worms); Mitochondrial morphology and fusion/fission regulators (DRP-1, MFN1/MFN2, form factor); Mitophagy dynamics in Tau/PTL-1 deficiency; ROS production and membrane potential changes; ROS-mediated hormesis and antioxidant effects (NAC) across conditions; Genetic dissection...

7/6/26 • 24:42

Norberg ES et al., Proceedings of the National Academy of Sciences - Using metal‑responsive fluorescent Salmonella reporters, calf intestinal loops, and CRISPR edited epithelial cells, this study shows that the divalent metal transporter SLC11A2 is recruited to Salmonella‑containing vacuoles and restricts Fe2+ and Mn2+, limiting intracellular bacterial replication. Key terms: SLC11A2, nutritional immunity, Salmonella enterica, iron and manganese, intestinal epithelium. Study Highlights:The authors used metal‑sensing GFP reporters in Salmonella and a calf ligated ileal loop model to map metal availability and found a subpopulation of bacteria in IECs and lamina propria cells exposed to ≤0.1 µM Fe2+ and Zn2+, and possibly Mn2+, early in infection. SLC11A2 localized to the apical surface and endosomal network of IECs and was recruited to maturing Salmonella‑containing vacuoles; CRISPR knockout of SLC11A2 in HCT116 epithelial cells increased bacterial replication. Fluorescent reporters and ICP‑MS indicate vacuolar STm are less starved for Fe2+ and Mn2+ in the absence of SLC11A2, while Zn2+ and Mg2+ sensing was unchanged. Salmonella counters SLC11A2‑mediated restriction through the Mn2+/Fe2+ transporter MntH and siderophore production. Conclusion:SLC11A2 mediates epithelial nutritional immunity by sequestering Fe2+ and Mn2+ in Salmonella‑containing vacuoles, reducing vacuolar metal availability and limiting intracellular Salmonella replication. Music:Enjoy the music based on this article at the end of the episode. Article title:SLC11A2 withholds divalent metals fromSalmonellain the gut epithelium First author:Norberg ES Journal:Proceedings of the National Academy of Sciences DOI:10.1073/pnas.2532675123 Reference:Norberg ES, Knodler LA, et al. SLC11A2 withholds divalent metals from Salmonella in the gut epithelium. PNAS. 2026;123:e2532675123. doi:10.1073/pnas.2532675123 License:This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support:Base by Base is independent and ad-free — no sponsors, no paywall. If an episode was worth your time, chip in and keep the papers audited and the original songs coming:❤️ Support monthly: https://buy.stripe.com/cNifZhclVebvagk2JDgEg01☕ One-time donation: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 More at basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/slc11a2-withholds-divalent-metals-from-salmonella QC:This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-07-05. QC Scope:- article metadata and core scientific claims from the narration- excludes analogies, intro/outro, and music- transcript coverage: Audited transcript sections covering nutritional immunity concepts, IEC-localized SLC11A2 function, calf ileal loop in vivo model, metal-responsive STm reporters, SLC11A2 recruitment to SCVs, SLC11A2 knockout effects in HCT116 cells, bacterial countermeasures (MntH and siderophores), intracellular niches (SCV vs cytoso- transcript topics: Nutritional immunity and trace metal tug-of-war; SLC11A2 (NRAMP2) in intestinal epithelial cells; Calf ligated ileal loop model and metal availability; Metal-responsive Salmonella reporters (iroN, sitA, zinT); SLC11A2 recruitment to Salmonella-containing vacuoles; SLC11A2 knockout in HCT116 cells and impact on Salmonella replication QC Summary:- factual score: 10/10- metadata score: 10/10- supported core claims: 6- claims flagged for review: 0- metadata chec...

7/5/26 • 21:54

Synowiec A et al., Proceedings of the National Academy of Sciences (PNAS) - This episode examines a PNAS study using fetal, pediatric, and adult human intestinal enteroids to show that physiological temperature and developmental stage jointly determine susceptibility to HCoV-229E, with implications for extrapulmonary coronavirus infection and therapeutic testing. Key terms: HCoV-229E, intestinal enteroids, temperature sensitivity, age-dependent susceptibility, ANPEP/TMPRSS2. Study Highlights:The authors used age-stratified human intestinal enteroids (HIEs) and compared infection at 32 °C and 37 °C, finding temperature-dependent transcriptional reprogramming. HCoV-229E productively infected HIEs from all ages at 32 °C, but at 37 °C replication was largely restricted to fetal and some pediatric tissues. Enterocytes were identified as the primary target cells and viral progeny were released apically. Inhibition of serine proteases with camostat significantly reduced HCoV-229E replication, supporting a TMPRSS2-like entry dependency. Conclusion:Physiological temperature and developmental maturity create a dual barrier that limits intestinal replication of HCoV-229E in adults at 37 °C while permitting broader replication at cooler, upper-airway-like temperatures; HIEs provide a platform to probe host determinants and test entry-directed inhibitors such as camostat. Music:Enjoy the music based on this article at the end of the episode. Article title:Temperature and developmental stage govern intestinal susceptibility to human coronavirus 229E First author:Synowiec A Journal:Proceedings of the National Academy of Sciences (PNAS) DOI:10.1073/pnas.2600632123 Reference:Synowiec A., Lie L.K., Szczepański A., et al. Temperature and developmental stage govern intestinal susceptibility to human coronavirus 229E. Proc. Natl. Acad. Sci. U.S.A. 2026;123(26):e2600632123. https://doi.org/10.1073/pnas.2600632123 License:This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support:Base by Base – Stripe donations: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 Official website https://basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/temp-age-hcov-229e-ep406 QC:This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-07-01. QC Scope:- article metadata and core scientific claims from the narration- excludes analogies, intro/outro, and music- transcript coverage: Audited the portions of the transcript describing: experimental design (age-stratified HIEs at 32°C vs 37°C), replication patterns of HCoV-229E (32°C broad permissivity; 37°C restricted), cell tropism (enterocytes as primary target), entry mechanism (ANPEP receptor, TMPRSS2 proteases), and protease inhibition (camostat- transcript topics: HCoV-229E infection in age-stratified human intestinal enteroids (HIEs); Temperature effects (32 °C vs 37 °C) on replication; Age dependence and donor variability; Cell type tropism and ANPEP/TMPRSS2 entry; Camostat inhibition and entry pathways; Limitations of the HIE model and translational implications QC Summary:- factual score: 10/10- metadata score: 10/10- supported core claims: 4- claims flagged for review: 0- metadata checks passed: 4- metadata issues found: 0 Metadata Audited:- article_doi- article_title- article_journal- license Factual Items Audited:- Three age groups of HIEs used: fetal, pediatric, adult- Seasonal HCoV...

7/1/26 • 19:53

Úbeda F et al., Proceedings of the National Academy of Sciences (PNAS) - A population-genetic model explains why sequence-specific PRDM9-guided recombination hotspots can evolve and persist alongside non-PRDM9 hotspots by trading off reduced overall binding for increased symmetric binding that more often yields crossovers. Key terms: PRDM9, recombination hotspots, biased gene conversion, symmetric binding, population genetics. Study Highlights:The authors develop a three-locus population genetic model and run analytical and numerical simulations to compare PRDM9-like (specific) versus non-PRDM9 (unspecific) hotspot mechanisms. They find non-PRDM9 hotspots are generally favored because they yield higher overall binding and more crossovers, but PRDM9 can be favored when symmetric binding more often resolves as crossovers. Intermediate parameter regimes permit stable coexistence or cyclical oscillations in the relative use of both hotspot types. The model makes testable predictions linking chromosome architecture and fertility costs to the evolutionary distribution of hotspot mechanisms. Conclusion:PRDM9 persistence reflects a trade-off: sequence specificity reduces average binding but increases symmetric homolog binding that can disproportionately raise crossover success; when the crossover-resolution advantage of symmetric binding outweighs binding loss, PRDM9 is favored or can coexist with non-PRDM9 mechanisms. Music:Enjoy the music based on this article at the end of the episode. Article title:On the origin of PRDM9-guided recombination hotspots First author:Úbeda F Journal:Proceedings of the National Academy of Sciences (PNAS) DOI:10.1073/pnas.2535682123 Reference:Úbeda F, Bürger R, Fyon F. On the origin of PRDM9-guided recombination hotspots. Proc Natl Acad Sci U S A. 2026;123(26):e2535682123. doi:10.1073/pnas.2535682123 License:This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support:Base by Base – Stripe donations: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 Official website https://basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/405-prdm9-hotspots QC:This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-07-01. QC Scope:- article metadata and core scientific claims from the narration- excludes analogies, intro/outro, and music- transcript coverage: Audited the transcript portions describing hotspot mechanisms, symmetric vs asymmetric binding, the three-locus model (modifier M, targeting A, target B), key results (dominance of non-PRDM9, potential PRDM9 advantage with symmetric binding, coexistence and oscillations), phylogenetic patterns and chromosome-size impli- transcript topics: PRDM9-guided recombination vs non-PRDM9 hotspots; Symmetric vs asymmetric binding in recombination; Three-locus population-genetic model (modifier, targeting, target loci); Evolutionary outcomes: dominance, coexistence, oscillations; Phylogenetic distribution and chromosome-size effects QC Summary:- factual score: 10/10- metadata score: 10/10- supported core claims: 4- claims flagged for review: 0- metadata checks passed: 4- metadata issues found: 0 Metadata Audited:- article_doi- article_title- article_journal- license Factual Items Audited:- Two hotspot mechanisms exist: PRDM9-guided (specific) and non-PRDM9 (open chromatin, sequence-independent).- PRDM9 hotspots erode via biased gene conversion; non-P...

7/1/26 • 23:33

Bošković F et al., Proceedings of the National Academy of Sciences - This study introduces RUNA, a reversible chemistry that selectively labels uridine/thymidine to map nucleic acids across membranes, and uses it to show that most exosomal DNA is surface-exposed, increases after PARP inhibitor treatment, and alters macrophage uptake and activation. Key terms: RUNA, exosomes, surface DNA, macrophage polarization, PARP inhibitor. Study Highlights:The authors developed Reversible Uridine Nitrilium-mediated Addition (RUNA), which selectively and reversibly modifies the N3 of uridine and thymidine via an in situ nitrilium ion. By varying aldehyde membrane permeability, RUNA distinguishes intra-vesicular from extravesicular nucleic acids. Applied to exosomes from MyC-CaP prostate cancer cells, RUNA shows most exosomal DNA is surface-exposed and nearly doubles after rucaparib (PARP inhibitor) treatment. Surface DNA promotes uptake by M2 macrophages through scavenger receptors and shifts them toward an M1-like proinflammatory profile. Conclusion:RUNA is a modular, reversible chemical tool to map nucleic acid accessibility across membranes; using it the authors reveal exosomal surface DNA as a dynamic, damage-responsive determinant of macrophage uptake and immune modulation with implications for tumor–immune interactions. Music:Enjoy the music based on this article at the end of the episode. Article title:A nucleic acid labeling chemistry reveals surface DNA on exosomes First author:Bošković F Journal:Proceedings of the National Academy of Sciences DOI:10.1073/pnas.2532281123 Reference:Bošković F, Dutta Gupta P, Zhang J, Szostak JW, Krishnan Y. A nucleic acid labeling chemistry reveals surface DNA on exosomes. Proc Natl Acad Sci U S A. 2026;123(27):e2532281123. doi:10.1073/pnas.2532281123 License:This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support:Base by Base – Stripe donations: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 Official website https://basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/runa-surface-dna-on-exosomes QC:This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-06-30. QC Scope:- article metadata and core scientific claims from the narration- excludes analogies, intro/outro, and music- transcript coverage: Audited sections describing RUNA mechanism, membrane-permeability tuning, exosome surface DNA, PARP-inhibitor effects on surface DNA, exosome uptake by M2 macrophages, macrophage polarization to an M1-like state, and study limitations.- transcript topics: RUNA mechanism and reversibility; Membrane permeability tuning to distinguish exRNA vs vesicular RNA; Exosome DNA topology: surface-exposed vs luminal; PARP inhibitor (rucaparib) effects on surface DNA; Exosome uptake by M2 macrophages via scavenger receptors; Macrophage polarization to M1-like state and cytokine changes QC Summary:- factual score: 10/10- metadata score: 10/10- supported core claims: 6- claims flagged for review: 0- metadata checks passed: 4- metadata issues found: 0 Metadata Audited:- article_doi- article_title- article_journal- license Factual Items Audited:- RUNA selectively labels uridine and thymidine at N3 to form a reversible covalent adduct.- The RUNA adduct is thermally reversible by heating (e.g., 95 C for 15 minutes).- Membrane-permeable vs membrane-impermeable aldehydes distinguish total...

6/30/26 • 21:02

Schnaiter et al et al., The American Journal of Human Genetics - Schnaiter et al. pooled Myriad MyChoice HRD+ CDx results from four cohorts (4,943 HGOC tumors) to test whether tumor HRD-related genomic instability scores (HRD-GIS) provide evidence for BRCA1 and BRCA2 variant classification under ACMG/AMP criteria. Key terms: homologous recombination deficiency, genomic instability score (HRD-GIS), BRCA1, BRCA2, MyChoice HRD+ CDx. Study Highlights:The authors analyzed 4,943 tumors (765 BRCApv, 4,178 BRCAwt) assessed with the MyChoice HRD+ CDx assay and found 91.0% of BRCApv tumors were GIShigh (≥42) versus 30.0% of BRCAwt. The pooled likelihood ratio (LR) that a variant is pathogenic in a GIShigh HGOC was 3.03 (95% CI: 2.88–3.19), mapping to supporting pathogenic evidence. Conversely, the pooled LR for GISlow (

6/26/26 • 22:51

Baya N et al., The American Journal of Human Genetics 113, 1–19 (2026) - Baya et al. applied a misalignment framework to UK Biobank polygenic scores and exomes and found that individuals whose observed phenotypes deviate from polygenic expectation are enriched for rare damaging variants across multiple traits and diseases. Key terms: polygenic scores, rare variants, misalignment, liability threshold, UK Biobank. Study Highlights:The authors define 'misaligned' individuals whose covariate-residualized phenotypes differ markedly from PGS expectation and test enrichment for rare (MAF

6/25/26 • 20:26

Fluri R et al., The American Journal of Human Genetics - This episode examines a cohort study of 16 individuals with de novo LDB1 variants that reveals two overlapping but distinct neurodevelopmental phenotypes tied to variant location. Functional assays and Drosophila models demonstrate loss-of-function effects for N-terminal variants and dominant-negative effects for C-terminal variants. Key terms: LDB1, neurodevelopmental disorder, ventriculomegaly, dominant-negative, haploinsufficiency. Study Highlights:The authors assembled 16 individuals with de novo LDB1 variants and mapped variants to the N-terminal dimerization domain or the C-terminal LIM interaction domain. In vitro assays showed N-terminal missense variants disrupt homodimerization leading to loss of function, while C-terminal variants impair LHX2 binding and act in a dominant-negative manner. Drosophila knockdown and overexpression corroborated dosage sensitivity and distinct in vivo effects, including rescue by wild-type LDB1 and worsening by C-terminal variants. Clinically, C-terminal LID-affecting variants associate with congenital ventriculomegaly and more frequent extra‑neural anomalies, whereas N-terminal variants tend to cause variable NDD without consistent brain malformations. Conclusion:Variant location in LDB1 predicts distinct pathomechanisms and overlapping clinical presentations: N-terminal variants cause haploinsufficiency/loss of function, while C-terminal LID variants act dominant-negatively and are linked to ventriculomegaly and broader organ involvement. Music:Enjoy the music based on this article at the end of the episode. Article title:De novo variants in LDB1 are linked to distinct neurodevelopmental phenotypes determined by variant location and differing pathomechanisms First author:Fluri R Journal:The American Journal of Human Genetics DOI:10.1016/j.ajhg.2026.05.012 Reference:Fluri R., Coll-Tané M., Brunet T., et al. De novo variants in LDB1 are linked to distinct neurodevelopmental phenotypes determined by variant location and differing pathomechanisms. The American Journal of Human Genetics. 2026;113:1–15. doi:10.1016/j.ajhg.2026.05.012 License:This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support:Base by Base – Stripe donations: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 Official website https://basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/ldb1-variant-location-pathomechanisms QC:This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-06-23. QC Scope:- article metadata and core scientific claims from the narration- excludes analogies, intro/outro, and music- transcript coverage: Audited sections describing LDB1 structure (DD and LID), variant spectrum (N-terminal vs C-terminal), two mechanisms (haploinsufficiency vs dominant-negative), cellular assays (protein levels, ubiquitination, aggregates), LDB1-LHX2 interactions, Drosophila chi model (dosage sensitivity, rescue/toxicity, sleep), and cli- transcript topics: LDB1 structure and domains (DD and LID); Variant spectrum across LDB1 (N-terminal vs C-terminal); Mechanisms: haploinsufficiency and dominant-negative effects; Cellular assays: protein stability, ubiquitination, aggregates; LDB1 interactions: dimerization and LHX2 binding; Drosophila model chi (chip) dosage sensitivity and experiments QC Summary:- factual score: 9/10- metadata score: 10/10- supported core claims: 7- claims flagged for review: 1

6/23/26 • 24:28

Mastrorosa F et al., The American Journal of Human Genetics - Long-read assemblies and epigenetic mapping of chromosome 21 centromeres in families with trisomy 21 reveal centromere size diversity, two cases of extreme maternal centromere size asymmetry, and no global enrichment of small centromeres in affected individuals. Key terms: trisomy 21, centromere, alpha-satellite, long-read sequencing, meiotic nondisjunction. Study Highlights:Using PacBio HiFi and ultra-long ONT reads with hybrid assembly and DiMeLo-seq, the authors fully resolved chr21 centromeres in eight T21 individuals and several parents and compared them to 287 population haplotypes. Small centromeres were not overall enriched in T21 cases, contradicting earlier reports, but two families showed extreme (>10-fold) maternal centromere size asymmetry. CDRs and CENP-A/CENP-C signals were present across haplotypes and methylation profiles were largely conserved between generations and sample types. Phylogenetic analysis indicates recent rapid evolution of chr21 centromere haplotypes that may facilitate such asymmetry. Conclusion:Centromere size alone does not explain trisomy 21 risk at the population level, but extreme maternal centromere size asymmetry appears in a minority of families and may contribute to nondisjunction in those cases. Music:Enjoy the music based on this article at the end of the episode. Article title:Complete chromosome 21 centromere sequencing of families with Down syndrome First author:Mastrorosa F Journal:The American Journal of Human Genetics DOI:10.1016/j.ajhg.2026.05.010 Reference:Mastrorosa F.K., Daponte A., de Gennaro L., et al. Complete chromosome 21 centromere sequencing of families with Down syndrome. The American Journal of Human Genetics. 113, 1–18 (2026). https://doi.org/10.1016/j.ajhg.2026.05.010 License:This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support:Base by Base – Stripe donations: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 Official website https://basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/chr21-centromere-sequencing-down-syndrome QC:This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-06-23. QC Scope:- article metadata and core scientific claims from the narration- excludes analogies, intro/outro, and music- transcript coverage: Audited transcript sections covering centromere structure, long-read sequencing workflow, extreme centromere size asymmetry findings, CpG/epigenetic mapping (CDRs, CENP-A/CENP-C), and population/evolutionary context.- transcript topics: Centromere structure and alpha-satellite HOR arrays; Maternal nondisjunction and Down syndrome etiology; Long-read sequencing technologies and hybrid phasing; Epigenetic centromere mapping (CDRs, CENP-A/CENP-C, CpG methylation); Centromere size asymmetry in Down syndrome families; Population diversity of chr21 centromeres (African ancestry four-mer HOR) QC Summary:- factual score: 10/10- metadata score: 10/10- supported core claims: 7- claims flagged for review: 0- metadata checks passed: 4- metadata issues found: 0 Metadata Audited:- article_doi- article_title- article_journal- license Factual Items Audited:- Small chr21 centromeres are not enriched in Down syndrome cases compared with controls (p = 0.72).- Extreme centromere size asymmetry (>10-fold) observed in two Down syndrome families (e.g., 10.7-fold... Chapters (00:00:20) - Down Syndrome: The mystery of the cell division(00:04:45) - Down Syndrome: The repetitive DNA handles(00:09:49) - Down Syndrome: The tug of war(00:14:16) - The genetics of trisomy 21(00:15:58) - Down Syndrome: The mystery of the genetic cause(00:20:13) - A Single Link in the Code

6/23/26 • 22:30

Shi Z et al., The American Journal of Human Genetics - A large GWAS meta-analysis across five biobanks (8,969 cases, 1,962,542 controls) identifies five genome-wide significant loci for Ménière disease, implicating developmental regulators EYA1/EYA4 and retinoic acid metabolism genes including CYP26A1. Integrative fine-mapping, eQTL, and single-cell expression place these signals in inner ear cell types and link MD to related sensory and neurological traits. Key terms: Ménière disease, EYA1, EYA4, retinoic acid, GWAS. Study Highlights:A GWAS meta-analysis of 8,969 Ménière disease cases and 1,962,542 controls across five biobanks identified five independent genome-wide significant loci, including two signals each at EYA4 and EYA1 and one near CYP26A1. Observed-scale SNP heritability was estimated at 7% (SE 0.8%), indicating a modest contribution of common variation. Fine-mapping, eQTL and single-cell expression data implicate dysregulation of inner ear developmental regulators and retinoic acid metabolism. Phenome-wide and genetic-correlation analyses reveal shared architecture with vertigo, tinnitus, hearing loss, migraine, and sleep apnea. Conclusion:Regulatory common variants in genes governing inner ear development (EYA1, EYA4) and retinoic acid signaling (CYP26A1/C1, ALDH1A2) contribute to Ménière disease risk, providing a genetic framework for functional follow-up and polygenic risk modeling. Music:Enjoy the music based on this article at the end of the episode. Article title:Genome-wide analysis implicates inner ear development in Ménière disease First author:Shi Z Journal:The American Journal of Human Genetics DOI:10.1016/j.ajhg.2026.05.011 Reference:Shi Z, Mandla R, Li J, et al. Genome-wide analysis implicates inner ear development in Ménière disease. The American Journal of Human Genetics. 2026;113:1–12. https://doi.org/10.1016/j.ajhg.2026.05.011 License:This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support:Base by Base – Stripe donations: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 Official website https://basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/base-by-base-399-meniere-inner-ear QC:This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-06-22. QC Scope:- article metadata and core scientific claims from the narration- excludes analogies, intro/outro, and music- transcript coverage: Substantive audit of the transcript's representation of GWAS scale, loci and genes (EYA4, EYA1, CYP26A1, ALDH1A2, LMO4), developmental/retinoic acid pathways, genetic correlations, limitations, and future directions as reported in the canonical article.- transcript topics: Genome-wide association study scale and meta-analysis across five biobanks; Identification of five independent signals: two at EYA4, two at EYA1, one near CYP26A1; EYA4 and EYA1 as developmental regulators of inner ear; Regulatory vs coding variants and gene expression implications; Retinoic acid signaling pathway involvement: CYP26A1/C1 and ALDH1A2; LMO4 as a suggestive signal and its developmental context QC Summary:- factual score: 10/10- metadata score: 10/10- supported core claims: 7- claims flagged for review: 0- metadata checks passed: 4- metadata issues found: 0 Metadata Audited:- article_doi- article_title- article_journal- license Factual Items Audited:- MD SNP-based heritability estimated at 7% (SE 0.8%) on the observ... Chapters (00:00:20) - The genetic basis of Meniere disease(00:02:04) - Scientists solve the genetic mystery of Meniere's disease(00:06:35) - The genetic heritability of Meniere's(00:10:18) - Genetics of Meniere's Disease and gl(00:15:35) - Genetic determinants of Meniere's

6/22/26 • 21:44

Snyder J et al., Proceedings of the National Academy of Sciences (PNAS) - Longitudinal VAF measurements from 67 JAK2V617F-positive participants in the Danish GESUS study were analyzed with a Moran-process stem cell model and ABC-SMC to infer per-individual self-renewal advantages and assess prognostic value for MPN progression. Key terms: JAK2V617F, clonal hematopoiesis, Moran model, myeloproliferative neoplasms, mathematical modeling. Study Highlights:The study follows 67 individuals from the GESUS cohort with >1% JAK2V617F VAF and multiple follow-up measurements over >10 years. A Moran-process model at the HSC level fitted by ABC-SMC reproduced longitudinal VAF trajectories for 66 of 67 subjects and yielded per-individual estimates of the mutant self-renewal advantage s. Results show heterogeneity: ~70% of subjects had a statistically positive s, ~18% had a negative s, and ~12% were neutral, indicating many carriers show no expansion or even contraction. The fitted model can predict future VAF evolution for most subjects but s alone is not a perfect predictor of MPN diagnosis. Conclusion:A stem-cell Moran-process model explains longitudinal JAK2V617F VAF dynamics in most GESUS participants; inferred selective advantage varies widely, correlates with—but does not fully predict—MPN diagnosis, supporting individualized monitoring and further study of non-VAF risk factors. Music:Enjoy the music based on this article at the end of the episode. Article title:Mathematical modeling of JAK2V617F clonal expansion in a general population cohort First author:Snyder J Journal:Proceedings of the National Academy of Sciences (PNAS) DOI:10.1073/pnas.2507773123 Reference:Snyder J, Andersen M, Gudmand-Høyer J, et al. Mathematical modeling of JAK2V617F clonal expansion in a general population cohort. Proc Natl Acad Sci U.S.A. 2026;123:e2507773123. doi:10.1073/pnas.2507773123 License:This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support:Base by Base – Stripe donations: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 Official website https://basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/base398-jak2v617f-moran QC:This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-06-21. QC Scope:- article metadata and core scientific claims from the narration- excludes analogies, intro/outro, and music- transcript coverage: Substantively audited sections include background on JAK2V617F and MPN, Moran process model with carrying capacity and generation time, ABC-SMC inference of per-subject s, results breakdown (positive/neutral/negative s and 66/67 fit), link between s and MPN progression, inflammation/CRP and statin discussion, and limit- transcript topics: JAK2V617F mutation and myeloproliferative neoplasms biology; Moran process model and stem cell carrying capacity; Inference of per-individual selective advantage (s) via ABC-SMC; VAF trajectories across individuals and fit to the model; Association between s and progression to MPN; imperfect prediction; Inflammation (CRP) and statins as modifiers of clonal dynamics QC Summary:- factual score: 10/10- metadata score: 10/10- supported core claims: 8- claims flagged for review: 0- metadata checks passed: 4- metadata issues found: 0 Metadata Audited:- article_doi- article_title- article_journal- license Factual Items Audited:- 67 individuals with >1% JAK2V617F VAF in... Chapters (00:00:00) - Can Your Body Naturally Suppress a Cancer Mutation?(00:05:30) - The genetics of JAK2 cancer(00:10:47) - The Stochastic Selection of MPN(00:16:05) - JAK2 mutation and the immune system

6/21/26 • 24:52

Seidel et al., Nature Communications - SciPhy is a BEAST2-integrated Bayesian framework that models sequential CRISPR‑based insertion edits to jointly infer time-scaled single-cell lineage trees, editing dynamics, and population growth. The authors validate SciPhy on simulations and apply it to HEK293T monoclonal expansion and murine gastruloid datasets, showing improved tree and branch-length inference relative to UPGMA and enabling phylodynamic estimates of growth. Key terms: Bayesian phylogenetics, lineage tracing, CRISPR, DNA Typewriter, phylodynamics. Study Highlights:SciPhy implements a mechanistic model of ordered, irreversible insertions with per-tape clock rates and insertion probabilities and computes the likelihood using a pruning algorithm within BEAST2. Validation on calibrated simulations shows correct posterior coverage and high correlations between true and inferred editing and tree parameters. Application to HEK293T and gastruloid data recovers per-tape edit rates and preferential insert probabilities, infers growth rates including time-varying dynamics in gastruloid development, and yields more accurate topologies and branch lengths than UPGMA. The framework reports uncertainty and enables joint phylodynamic analysis of lineage tracing data. Conclusion:A mechanistic, order-aware Bayesian model for sequential genome-editing lineage recorders improves reconstruction of time-calibrated cell lineage trees, quantifies editing biases and clock rates, and enables inference of cell population dynamics from single-cell lineage tracing data. Music:Enjoy the music based on this article at the end of the episode. Article title:SciPhy: A Bayesian phylogenetic framework using sequential genetic lineage tracing data First author:Seidel Journal:Nature Communications DOI:10.1038/s41467-026-73377-6 Reference:Seidel, S., Zwaans, A., Regalado, S. et al. SciPhy: A Bayesian phylogenetic framework using sequential genetic lineage tracing data. Nat Commun (2026). https://doi.org/10.1038/s41467-026-73377-6 License:This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support:Base by Base – Stripe donations: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 Official website https://basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/sciphy-bayesian-lineage-tracing QC:This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-06-20. QC Scope:- article metadata and core scientific claims from the narration- excludes analogies, intro/outro, and music- transcript coverage: Substantive auditing of the transcript's description of SciPhy's mechanistic model (ordered CRISPR edits), BEAST2 implementation, validation results, HEK293T monoclonal expansion, gastruloid development with CHIR treatment, and discussed limitations and computational considerations.- transcript topics: Mechanistic editing model with ordered inserts; BEAST2 integration and likelihood calculation; Editing rate clock rates and insertion probabilities; Validation: in-silico, HEK293T monoclonal expansion; Insertion bias: CAT vs GCG; Growth dynamics and phylodynamic inference QC Summary:- factual score: 10/10- metadata score: 10/10- supported core claims: 7- claims flagged for review: 0- metadata checks passed: 4- metadata issues found: 0 Metadata Audited:- article_doi- article_title- article_journal- license Factual Items Audited:- SciPhy is a Bayesian framewor...

6/20/26 • 23:27

Stannard A et al., Proceedings of the National Academy of Sciences (PNAS) - This episode summarizes a PNAS study that uses a FRET-responsive DNA tweezers nanosensor to detect and quantify sequence-dependent interactions between intact double-stranded DNA duplexes in ionic solutions. Key terms: homologous recognition, double-stranded DNA, electrostatic interactions, DNA nanosensor, divalent cations. Study Highlights:Using a tuned DNA-tweezers FRET assay, the authors show that homologous dsDNA duplexes coalign more readily than heterologous ones in the presence of divalent cations. They quantify a homologous recognition free energy of roughly −0.02 kBT (≈ −0.01 kcal/mol) per base pair and show this is largely independent of Mg2+ versus Ca2+ within the tested range. Controls exclude strand exchange and sequence-specific ion adsorption as alternative explanations. An electrostatic helical coherence model reproduces the magnitude and salt dependence of the measured effect. Conclusion:Protein-free, sequence-specific electrostatic interactions between intact dsDNA can produce a small but measurable homology recognition energy consistent with helical coherence theory and relevant under confined, DNA-rich conditions. Music:Enjoy the music based on this article at the end of the episode. Article title:Direct evidence and quantification of homologous recognition between DNA duplexes First author:Stannard A Journal:Proceedings of the National Academy of Sciences (PNAS) DOI:10.1073/pnas.2530949123 Reference:Stannard A., Haimov E., Hedley J.G., et al. Direct evidence and quantification of homologous recognition between DNA duplexes. Proc. Natl. Acad. Sci. U.S.A. 2026; doi:10.1073/pnas.2530949123. License:This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support:Base by Base – Stripe donations: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 Official website https://basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/homologous-dna-recognition-396 QC:This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-06-18. QC Scope:- article metadata and core scientific claims from the narration- excludes analogies, intro/outro, and music- transcript coverage: Audited the transcript portions describing the DNA tweezers design and readout, cation dependence, homologous vs heterologous comparison, longer-duplex effects, strand-exchange controls, helical-coherence theory, and cellular relevance.- transcript topics: DNA tweezers design and FRET readout; Monovalent vs divalent cation effects on duplex coalignment; Homologous versus heterologous sequence comparisons; Strand-exchange controls and GC clamps; Length dependence: 36 bp vs 68 bp and entropic effects; Helical coherence theory mechanism and charge patterning QC Summary:- factual score: 10/10- metadata score: 10/10- supported core claims: 7- claims flagged for review: 0- metadata checks passed: 4- metadata issues found: 0 Metadata Audited:- article_doi- article_title- article_journal- license Factual Items Audited:- Direct evidence for homologous recognition between intact dsDNA in protein-free ionic conditions.- Recognition energy per base pair is about -0.02 kBT (≈ -0.01 kcal/mol per base pair).- Recognition is largely independent of whether Mg2+ or Ca2+ is the divalent cation and of their concentration within tested range.- Divalent cations promote coalignme...

6/18/26 • 23:26

Green R et al., PNAS - Collating >100,000 base-pair substitutions from 32 mutation-accumulation experiments, this study shows that sequence context well beyond adjacent bases — up to ±6 bp and even hundreds of bp — shapes mutational biases in E. coli and interacts with DNA repair. Key terms: mutational bias, sequence context, Escherichia coli, mismatch repair, mononucleotide runs. Study Highlights:The authors analyzed 117,807 base-pair substitutions from 32 MA experiments and quantified nucleotide frequencies up to ±6 bp (and sliding windows to 1,000 bp) around mutation sites. Extended context effects vary by substitution type, DNA repair background (proofreading and MMR), and replication strand. Mononucleotide runs (notably AC3+ and GC3+) are strong hotspots consistent with transient misalignment; GC3+ can increase G:C→C:G transversions by orders of magnitude. Broader GC% biases persist hundreds of base pairs and are modulated by MMR activity. Conclusion:Extended sequence context and its interaction with proofreading, mismatch repair, and replication strand identity create complex, BPS-specific mutational signatures in E. coli, improving the resolution of mutation-rate predictions and highlighting long-range and motif-specific hotspots. Music:Enjoy the music based on this article at the end of the episode. Article title:Extended sequence context shapes mutational bias in Escherichia coli First author:Green R Journal:PNAS DOI:10.1073/pnas.2601345123 Reference:Green R., Jago M.J., Knight C.G., Czernuszka M.R., Denisova S., Krašovec R., Lagator M. Extended sequence context shapes mutational bias in Escherichia coli. PNAS. 2026;123(23):e2601345123. doi:10.1073/pnas.2601345123. License:This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support:Base by Base – Stripe donations: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 Official website https://basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/extended-sequence-context-mutational-bias-e-coli QC:This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-06-18. QC Scope:- article metadata and core scientific claims from the narration- excludes analogies, intro/outro, and music- transcript coverage: Audited sections covering extended sequence context (±6 bp), mononucleotide run hotspots (AC3+, GC3+), GC3+ and G:C→C:G transversions, 5′ preceding nucleotide effects, leading vs lagging strand replication, and GC-content effects up to 1000 bp.- transcript topics: Extended sequence context (±6 bp); Mononucleotide runs and transient misalignment; GC3+ hotspot and other motifs; DNA proofreading and mismatch repair effects; Leading vs lagging strand replication and context biases; Regional GC-content effects up to 1000 bp QC Summary:- factual score: 10/10- metadata score: 10/10- supported core claims: 6- claims flagged for review: 0- metadata checks passed: 4- metadata issues found: 0 Metadata Audited:- article_doi- article_title- article_journal- license Factual Items Audited:- Extended context up to ±6 bp influences mutational bias beyond trinucleotide context- Mononucleotide runs AC3+ and GC3+ are mutational hotspots; GC3+ increases G:C→C:G transversions up to ~10^4-fold- A strong GC3+ hotspot near GG sequences can reach extremely large fold increases; in some backgrounds ~50,000-fold for G:C→C:G transversions at GG C7- 5′ preceding nucleotide...

6/18/26 • 22:43

Gaudio HA et al., Nature Communications - This episode examines a systematic benchmark of six commercial large language models applied to plasma cell-free RNA across three clinical cohorts, assessing LLM-driven gene-panel nomination and autonomous classifier construction versus conventional statistical workflows. Key terms: large language models, cell-free RNA, biomarker discovery, machine learning, diagnostics. Study Highlights:Six state-of-the-art LLMs were tested on cfRNA datasets from Kawasaki disease vs MIS-C, tuberculosis vs symptomatic controls, and ME/CFS vs sedentary controls for gene-panel nomination and end-to-end classifier building. LLM-nominated panels recapitulated canonical immune pathways and outperformed random gene sets, matching differential expression–derived panels in the tuberculosis cohort. End-to-end automation was feasible but model- and task-dependent: OpenAI o3 matched conventional performance for KD vs MIS-C but underperformed for TB and ME/CFS. Models showed prompt-adherence issues and sometimes returned non-reference or hallucinated features, which limits reproducibility. Conclusion:Current LLMs can extract biologically meaningful cfRNA candidate panels and partially automate biomarker workflows, but results are variable and traditional or hybrid statistical workflows remain necessary; rigorous validation and constrained output schemas are required before clinical deployment. Music:Enjoy the music based on this article at the end of the episode. Article title:Benchmarking large language models for cell-free RNA diagnostic biomarker discovery First author:Gaudio HA Journal:Nature Communications DOI:10.1038/s41467-026-74077-x Reference:Gaudio HA, Bliss A, Loy CJ, Eweis‑LaBolle D, Gardella AE & De Vlaminck I. Benchmarking large language models for cell-free RNA diagnostic biomarker discovery. Nature Communications (2026). doi:10.1038/s41467-026-74077-x License:This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support:Base by Base – Stripe donations: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 Official website https://basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/benchmarking-llms-cfrna QC:This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-06-17. QC Scope:- article metadata and core scientific claims from the narration- excludes analogies, intro/outro, and music- transcript coverage: Substantively audited the transcript's coverage of the study design, LLM benchmarking across three cohorts, gene-panel nomination, end-to-end classifier construction, prompt effects, and the hybrid-workflow conclusions, with reference to supporting results in the article.- transcript topics: Study design and cohorts (KD vs MIS-C, TB vs symptomatic controls, ME/CFS vs sedentary controls); Prompt adherence and gene-panel nomination; Comparison of LLM panels to random and DGE panels; End-to-end classifier construction and cross-cohort performance; Disease-informed vs disease-naïve prompts impact; Limitations: probability calibration, data leakage concerns QC Summary:- factual score: 10/10- metadata score: 10/10- supported core claims: 5- claims flagged for review: 0- metadata checks passed: 4- metadata issues found: 0 Metadata Audited:- article_doi- article_title- article_journal- license Factual Items Audited:- Six LLMs were evaluated across three cohorts: OpenAI o3, GPT-4o, Claude...

6/17/26 • 22:34

Vambe D et al., Nature Communications - This study reports the programmatic introduction of targeted next-generation sequencing (tNGS) in Eswatini and shows that tNGS detected large amounts of rifampicin and bedaquiline resistance missed by routine diagnostics. Among 234 patient samples, tNGS reclassified many infections, revealed frequent co-occurrence of rpoB I491F and Rv0678 mutations, and guided treatment changes with high treatment success in a clinical subset. Key terms: tNGS, rifampicin-resistance, rpoB I491F, bedaquiline resistance, Eswatini. Study Highlights:tNGS detected rifampicin resistance in 159/234 strains, substantially more than Xpert Ultra, LPA, or MGIT pDST, and identified 101 strains with the rpoB I491F mutation (96 solo). Mutations in Rv0678 associated with bedaquiline/clofazimine resistance were found in 87 strains, occurring in 55% of rifampicin-resistant isolates and frequently co-occurring with rpoB I491F. Routine diagnostics under-classified resistance leading to incorrect regimen selection for many patients. In a subset of 59 patients with clinical data, tNGS-informed changes were made for 53% and treatment success was 88%. Conclusion:Programmatic tNGS in Eswatini closed a major diagnostic gap by identifying rifampicin resistance due to rpoB I491F and widespread Rv0678-associated bedaquiline resistance undetected by routine tests, enabling regimen changes and prompting reconsideration of current treatment algorithms and resistance classifications. Music:Enjoy the music based on this article at the end of the episode. Article title:Targeted next-generation sequencing implementation in Eswatini identifies rifampicin and bedaquiline resistance undetected by routine diagnostic testing First author:Vambe D Journal:Nature Communications DOI:10.1038/s41467-026-73551-w Reference:Vambe D, Kay A, Ziyane M, et al. Targeted next-generation sequencing implementation in Eswatini identifies rifampicin and bedaquiline resistance undetected by routine diagnostic testing. Nat Commun. 2026. https://doi.org/10.1038/s41467-026-73551-w License:This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support:Base by Base – Stripe donations: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 Official website https://basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/hidden-resistance-tngs-eswatini QC:This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-06-17. QC Scope:- article metadata and core scientific claims from the narration- excludes analogies, intro/outro, and music- transcript coverage: Audited the main results and implications discussed in the transcript: programmatic tNGS implementation, diagnostic gaps (I491F), BDQ resistance via Rv0678, comparison with routine diagnostics, regimen changes and outcomes, and WHO classification implications.- transcript topics: Diagnostic escape and rpoB I491F; tNGS programmatic implementation in Eswatini; BDQ resistance and Rv0678 mutations; Comparison of tNGS with Xpert Ultra, LPA, and MGIT pDST; Clinical impact: treatment changes and outcomes; WHO tuberculosis resistance classifications and implications QC Summary:- factual score: 10/10- metadata score: 10/10- supported core claims: 6- claims flagged for review: 0- metadata checks passed: 4- metadata issues found: 0 Metadata Audited:- article_doi- article_title- article_journal- license Factual Items Audited:-...

6/17/26 • 21:20

Lara MK et al et al., Nature Communications - Large GWAS in 836 outbred HS rats identifies six loci linked to cocaine self-administration traits, highlighting Ces1 carboxylesterase genes and other loci overlapping human substance-use genetics. Key terms: cocaine use disorder, GWAS, Heterogeneous Stock rats, Ces1, addiction-like behavior. Study Highlights:The study performed a genome-wide association analysis in 836 Heterogeneous Stock rats tested in extended-access cocaine self-administration paradigms and derived 27 behavioral traits. Six genome-wide significant loci were identified, including a chromosome 19 locus containing missense variants in Ces1c and Ces1d that are orthologous to human CES1 and associated with post-infusion interval. SNP-based heritability for traits was modest (h2 = 0.07–0.16) with the first LgA principal component showing the highest heritability (h2 = 0.16). Several loci contained coding variants and eQTL/sQTLs in brain regions, and one locus overlapped the rat homolog of human TRAK2. Conclusion:This largest-to-date rat GWAS of cocaine self-administration implicates drug-metabolizing carboxylesterases (Ces1c/Ces1d) and multiple neural genes in addiction-like behaviors, supports cross-species links to human SUD loci such as TRAK2, and highlights CES1-related pharmacological strategies as a potential avenue for follow-up. Music:Enjoy the music based on this article at the end of the episode. Article title:Genome-wide association study of cocaine self-administration behavior in Heterogeneous Stock rats First author:Lara MK et al Journal:Nature Communications DOI:10.1038/s41467-026-73694-w Reference:Lara MK et al., Genome-wide association study of cocaine self-administration behavior in Heterogeneous Stock rats. Nature Communications (2026). https://doi.org/10.1038/s41467-026-73694-w License:This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support:Base by Base – Stripe donations: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 Official website https://basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/gwas-cocaine-hs-rats-ces1 QC:This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-06-12. QC Scope:- article metadata and core scientific claims from the narration- excludes analogies, intro/outro, and music- transcript coverage: Audited portions of the transcript that cover: HS rat GWAS design and results; the chromosome 19 Ces1c/Ces1d locus and its link to post-infusion interval; metabolic role of Ces1 in cocaine breakdown; cross-species Trak2 findings; Rasd2/Gnas brain-region eQTLs; PC1 heritability; and broader discussion of implications an- transcript topics: Gwas in heterogeneous stock rats and six significant loci; Chromosome 19 Ces1c/Ces1d locus and post-infusion interval; Carboxylesterase Ces1 enzymes metabolizing cocaine; Trak2/TRAK2 cross-species overlap with human CUD; Rasd2 and Gnas expression in nucleus accumbens and cortex; LgA PC1 addiction-like behavior and heritability QC Summary:- factual score: 10/10- metadata score: 10/10- supported core claims: 6- claims flagged for review: 0- metadata checks passed: 4- metadata issues found: 0 Metadata Audited:- article_doi- article_title- article_journal- license Factual Items Audited:- Six genome-wide significant associations identified for cocaine self-administration traits in HS rats- Chromosome 19 locus containing...

6/12/26 • 23:23

Dr. Sandra Kaufmann, The Kaufmann Anti-Aging Institute - Dr. Sandra Kaufmann — physician, scientist and athlete — set out to understand aging and fight it with science. This episode is a guided overview of her book, featured with the author's permission: why our cells age (mitochondria, genetic information systems, quality control and maintenance, immunity, and waste management) and the families of anti-aging molecules she reviews (resveratrol, astaxanthin, NAD, curcumin, metformin, melatonin and more) — framed as an informed, individualized approach rather than a quick fix. Key terms: aging, longevity, anti-aging molecules, cellular biology, Kaufmann Protocol. Study Highlights:The book maps aging onto cellular causes — declining mitochondria, genetic information systems, cellular quality control and maintenance, immune changes, and waste management — and then reviews the leading molecules and adjuvants that target these pathways. Dr. Kaufmann turns the science into the basis for an informed, personalized plan, stressing that it is not a diet or quick fix and that decisions about supplements should be made together with a physician. Conclusion:Aging has identifiable biological drivers, and a science-literate, individualized approach — discussed with a physician — can help people age more deliberately rather than passively. Presented as Dr. Kaufmann's perspective, featured with the author's permission. Title: The Kaufmann Protocol: Why We Age and How to Stop It Reference: Kaufmann, S.C. The Kaufmann Protocol: Why We Age and How to Stop It. Jacob Cerny (Ed.), Ross Goldstein (Illus.). Kaufmann Anti-Aging Institute, 2018. ISBN 978-0-692-08904-0. ISBN: 978-0-692-08904-0 License:This episode is a guided overview of the book "Why We Age and How to Stop It: The Kaufmann Protocol" by Dr. Sandra Kaufmann, featured and adapted with the kind permission of the author. Support:Base by Base – Stripe donations: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 Official website https://basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.castos.com/episodes/kaufmann-protocol-why-we-age QC:This episode is a guided overview of the book "Why We Age and How to Stop It — The Kaufmann Protocol" by Dr. Sandra Kaufmann, featured with the author's kind permission and reviewed for editorial accuracy. QC Summary:- verdict: pass- review mode: book overview (author-authorized)- framing: presented as the author's perspective and synthesis- note: educational content only — not medical advice; decisions about supplements should be made with a physician

6/12/26 • 66:28

Gätgens C et al., PNAS - This episode examines how DNA-intercalating molecules like daunorubicin block bacteriophage infection at an early stage, causing an abortive-infection-like outcome via toxic phage products and showing synergy with nucleic-acid targeting defenses. Key terms: daunorubicin, abortive infection, bacterial immunity, phage-host interactions, DNA intercalators. Study Highlights:Using the E. coli BASEL phage collection, the authors mapped taxon-specific phage sensitivities to daunorubicin and other intercalators. For the Tequintavirus Bas33, daunorubicin blocks infection after first-step transfer, restricting expression to pre-early genes and preventing genome replication. Continued expression of these pre-early host-takeover genes leads to host cell death driven by toxic phage products, a process described as mutual destruction. Daunorubicin can act synergistically with restriction-modification systems to prevent accumulation of toxic phage products and enable population survival. Conclusion:DNA-intercalating small molecules act as a chemical layer of bacterial antiphage defense that can block infection at defined stages and, depending on host context and additional immune systems, produce outcomes ranging from mutual destruction to population-level protection via synergy with nucleic-acid targeting defenses. Music:Enjoy the music based on this article at the end of the episode. Article title:DNA-intercalating antiphage molecules trigger abortive infection through mutual destruction and synergize with bacterial immunity First author:Gätgens C Journal:PNAS DOI:10.1073/pnas.2602073123 Reference:Gätgens C., Rackow B., Ernst L., et al. DNA-intercalating antiphage molecules trigger abortive infection through mutual destruction and synergize with bacterial immunity. PNAS. 2026;123(23):e2602073123. https://doi.org/10.1073/pnas.2602073123 License:This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support:Base by Base – Stripe donations: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 Official website https://basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/daunorubicin-mutual-destruction QC:This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-06-09. QC Scope:- article metadata and core scientific claims from the narration- excludes analogies, intro/outro, and music- transcript coverage: Audited the central mechanistic narrative and experimental results: daunorubicin action after first-step transfer, pre-early gene expression, mutual destruction phenotype, phage-specific sensitivity (Bas33 vs T4), and synergistic effects with RM systems EcoRV and EcoP1_I; plus methodological approaches and discussed li- transcript topics: DNA-intercalating chemical defense concept; Daunorubicin action on BASEL phage collection; First-step transfer and pre-early gene expression; Mutual destruction vs abortive infection phenotype; Phage taxonomic sensitivity patterns (Bas33 vs T4); Restriction-modification systems and daunorubicin synergy QC Summary:- factual score: 10/10- metadata score: 10/10- supported core claims: 7- claims flagged for review: 0- metadata checks passed: 4- metadata issues found: 0 Metadata Audited:- article_doi- article_title- article_journal- license Factual Items Audited:- Daunorubicin blocks Bas33 infection after first-step transfer (FST), with transcription largely restricted to pre-ea...

6/9/26 • 22:59

PNAS - This study identifies crotonylation as a posttranslational modification of c-Myc that reduces its transcriptional and oncogenic activity. Key lysines K289 and K298 are crotonylated; loss of crotonylation (including a cancer-derived K298N mutant) enhances Skp2 binding and tumorigenesis. Key terms: c-Myc, crotonylation, Skp2, posttranslational modification, oncogenesis. Study Highlights:The authors mapped ten crotonylated lysine residues on c-Myc and identified K289 and K298 as critical sites. Mutating these residues (2R or 8R mutants) increased c-Myc transcriptional activity, cell proliferation, colony formation, and promoter occupancy. Mechanistically, loss of crotonylation strengthened c-Myc binding to the E3 ligase Skp2 and reduced binding to p14ARF, linking crotonylation status to Skp2-mediated activation and turnover. A cancer-derived K298N mutation recapitulated enhanced transcriptional activity and produced larger xenograft tumors in mice. Conclusion:Crotonylation at specific C-terminal lysines restrains c-Myc oncogenic activity by limiting Skp2 interaction; disruption of this modification (including K298N) promotes transcriptional activation and tumor growth. Music:Enjoy the music based on this article at the end of the episode. Article title:Crotonylation impedes c-Myc oncogenic activity Journal:PNAS DOI:10.1073/pnas.2530020123 Reference:https://doi.org/10.1073/pnas.2530020123 License:This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support:Base by Base – Stripe donations: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 Official website https://basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/crotonylation-impedes-c-myc-activity QC:This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-06-09. QC Scope:- article metadata and core scientific claims from the narration- excludes analogies, intro/outro, and music- transcript coverage: Audited core scientific narrative: discovery of c-Myc crotonylation in human cells, identification of K289 and K298, mutational analyses (2R/8R), mechanistic link to Skp2 and transcriptional activation, in vivo K298N mutation and xenograft data, gut microbiota and crotonyl-CoA biology, and structural context via AlphaF- transcript topics: c-Myc crotonylation in human cells; K289 and K298 crotonylation sites; crotonylation-deficient mutants 2R/8R and proliferation; Skp2 interaction and ARF competition; transcriptional activation and promoter occupancy; K298N cancer-derived mutant in vivo QC Summary:- factual score: 10/10- metadata score: 10/10- supported core claims: 6- claims flagged for review: 0- metadata checks passed: 4- metadata issues found: 0 Metadata Audited:- article_doi- article_title- article_journal- license Factual Items Audited:- c-Myc is crotonylated in human cells at K289 and K298.- Crotonylation reduces binding of c-Myc to Skp2, dampening transcriptional activation.- Crotonylation-deficient mutants (2R and 8R) increase cellular proliferation and colony formation across multiple cell lines.- The cancer-derived K298N mutation shows increased transcriptional activity and oncogenic potential in vitro and in vivo.- K289R and K298R substitutions abolish crotonylation at these sites and enhance Skp2 binding while reducing ARF interaction.- AlphaFold predicts crotonylation drives a more compact, less disordered c-Myc conformation, imp...

6/9/26 • 25:28

Huang X et al., Proceedings of the National Academy of Sciences (PNAS) - This episode summarizes a PNAS study reporting CD163‑targeted lipid nanoparticles that deliver FAP‑specific CAR mRNA to liver macrophages in situ, producing CAR‑macrophages that clear activated hepatic stellate cells and promote fibrosis resolution in mouse models. Key terms: FAP‑CAR, macrophage, lipid nanoparticles, liver fibrosis, MMP12. Study Highlights:The authors engineered CD163 antibody–conjugated LNPs (αCD163/LNP‑FAPCAR) to selectively transduce liver macrophages with FAP‑targeting CAR mRNA, yielding in situ CAR‑macrophages. CAR‑M showed enhanced phagocytosis and cytotoxicity toward FAP+ hepatic stellate cells and activated Syk/MyD88/NF‑κB signaling, with induction of MMP12. In multiple mouse fibrosis models (CCl4, BDL, MCD diet), treatment reduced ECM and fibrosis markers, improved histology and hepatocyte regeneration, and reshaped macrophage subsets toward MMP12+ scar‑resolving states. Safety profiling showed no major organ toxicity in treated mice, though immunogenicity and off‑target distribution require further study. Conclusion:αCD163/LNP‑FAPCAR enables in situ generation of CAR‑macrophages that selectively eliminate FAP+ activated HSCs, reprogram macrophages toward reparative MMP12+ phenotypes, and reverse liver fibrosis in preclinical models, supporting further translational and safety evaluation. Music:Enjoy the music based on this article at the end of the episode. Article title:mRNA‑laden LNP‑enabled in situ CAR‑macrophage alleviates liver fibrosis via inhibiting activated HSCs and modulating the immune microenvironment First author:Huang X Journal:Proceedings of the National Academy of Sciences (PNAS) DOI:10.1073/pnas.2534673123 Reference:Huang X, Wang J, Hao J, et al. mRNA‑laden LNP‑enabled in situ CAR‑macrophage alleviates liver fibrosis via inhibiting activated HSCs and modulating the immune microenvironment. Proc. Natl. Acad. Sci. U.S.A. 2026;123(22):e2534673123. doi:10.1073/pnas.2534673123. Published May 29, 2026. License:This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support:Base by Base – Stripe donations: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 Official website https://basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/in-situ-car-macrophage-liver-fibrosis QC:This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-06-09. QC Scope:- article metadata and core scientific claims from the narration- excludes analogies, intro/outro, and music- transcript coverage: Audited the transcript sections detailing αCD163/LNP-FAPCAR design, CAR-M macrophage generation in vivo, in vitro phagocytosis/cytotoxicity, in vivo fibrosis outcomes, scRNA-seq SAM/MMP12 reprogramming, human macrophage applicability, and safety considerations.- transcript topics: CD163-targeted LNPs delivering FAPCAR mRNA; CAR-M macrophage architecture (CD3zeta with CD28); In vitro phagocytosis and cytotoxicity against FAP+ cells; Syk/Myd88/NF-kB signaling and MMP12 induction; In vivo mouse liver fibrosis models and outcomes; Biodistribution and persistence of αCD163/LNP-FAPCAR QC Summary:- factual score: 10/10- metadata score: 10/10- supported core claims: 7- claims flagged for review: 0- metadata checks passed: 4- metadata issues found: 0 Metadata Audited:- article_doi- article_title- article_journal- license Factual Items Audited:- Ta...

6/9/26 • 21:01

Andrade J et al., PNAS - Analysis of three long-term cohorts in the Philippines and Thailand shows antibody titers wane over years and that homotypic dengue reinfections are common and required to explain population-level age–titer patterns. Key terms: dengue, homotypic reinfection, antibody kinetics, cohort study, mathematical modelling. Study Highlights:The authors analyzed serology and PCR surveillance from three cohorts (N = 4,268) in Cebu, Philippines and Kamphaeng Phet, Thailand with up to 11 years of follow-up. Individual titers after infection show biexponential decay: a rapid short-term fall (~2 months half-life) followed by a slow long-term decline (half-life ~4–8 years) that slows with age. Catalytic models that allow waning homotypic immunity and reinfection are required to reproduce observed age-specific infection rates and mean titers, estimating many individuals experience multiple homotypic reinfections across life in high-endemic settings. Conclusion:Waning long-term antibody titers and consequent homotypic reinfections are a key feature of endemic dengue transmission; vaccines that mimic natural infection may not provide lifelong protection and control strategies should account for repeated immune-stimulating events across ages. Music:Enjoy the music based on this article at the end of the episode. Article title:Long-term antibody dynamics challenge the paradigm of lifelong homotypic immunity to dengue virus First author:Andrade J Journal:PNAS DOI:10.1073/pnas.2606206123 Reference:Andrade J, Mitard de Girardie A, Huang AT, et al. Long-term antibody dynamics challenge the paradigm of lifelong homotypic immunity to dengue virus. PNAS. 2026;123(22):e2606206123. doi:10.1073/pnas.2606206123 License:This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support:Base by Base – Stripe donations: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 Official website https://basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/homotypic-reinfection-dengue QC:This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-06-09. QC Scope:- article metadata and core scientific claims from the narration- excludes analogies, intro/outro, and music- transcript coverage: Audited the transcript's coverage of dengue immunity dynamics, cohort data, subclinical infection prevalence, modeling of homotypic reinfection, age-related patterns, and public health/vaccine implications. Also checked limitations and caveats discussed in the article are echoed in the transcript.- transcript topics: DENV serotypes and lifelong immunity paradigm; Cohort data and serology methods (PRNT, HI); Subclinical infections and catalytic modeling; Two-phase antibody decay (short-term and long-term); Homotypic reinfection and population immunity; Age-specific infection risk and force of infection QC Summary:- factual score: 10/10- metadata score: 10/10- supported core claims: 6- claims flagged for review: 0- metadata checks passed: 4- metadata issues found: 0 Metadata Audited:- article_doi- article_title- article_journal- license Factual Items Audited:- Three cohorts totaling N = 4,268 participants across Cebu, Philippines and Kamphaeng Phet, Thailand- Approximately 94% of infections are subclinical- Antibody titers show biexponential decay after infection: a rapid short-term drop followed by a slower long-term decline- Short-term h...

6/9/26 • 21:36

Peeters MKR et al., Proceedings of the National Academy of Sciences (PNAS) - A perspective outlining how genome doubling (polyploidy) reshapes genomes, phenotypes, and ecological interactions and how its immediate effects can be harnessed across agriculture, aquaculture, industrial biotechnology, and medicine to advance a sustainable bioeconomy. Key terms: polyploidy, bioeconomy, genetic diversity, stress tolerance, biotechnology. Study Highlights:Polyploidization (whole-genome duplication) often produces novel phenotypes by shifting gene expression, metabolism, and morphology, which can increase biomass, diversify metabolites, and enhance stress tolerance. The paper synthesizes applications across green, blue, white, and red bioeconomies, including crop improvement, algal biofuel and pharmaceutical production, polyploid industrial strains, and ploidy-based biocontainment in aquaculture. Practical methods discussed include induced polyploidy, doubled-haploid breeding, triploid sterility, and adaptive laboratory evolution. Outcomes are promising but variable and require careful phenotypic, ecological, and evolutionary assessment due to risks like genomic instability. Conclusion:Polyploidization is a shared mechanism that can generate increased genetic diversity, expanded metabolic capacity, and altered morphology useful across bioeconomy sectors, but its benefits are variable and must be paired with rigorous phenotypic and ecological evaluation to manage risks and guide responsible innovation. Music:Enjoy the music based on this article at the end of the episode. Article title:Polyploidy: A macromutational force pushing bioeconomic developments First author:Peeters MKR Journal:Proceedings of the National Academy of Sciences (PNAS) DOI:10.1073/pnas.2522065123 Reference:Peeters MKR & Van de Peer Y (2026). Polyploidy: A macromutational force pushing bioeconomic developments. Proc. Natl. Acad. Sci. U.S.A. 123:e2522065123. https://doi.org/10.1073/pnas.2522065123 License:This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support:Base by Base – Stripe donations: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 Official website https://basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/polyploidy-bioeconomy QC:This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-06-05. QC Scope:- article metadata and core scientific claims from the narration- excludes analogies, intro/outro, and music- transcript coverage: Audited the core scientific content: mechanics of polyploidy, induction methods (Colchicine, DH breeding, triploidy, shocks), giga s effects, cross-domain applications (green/blue/white/red), and cancer-related polyploidy dynamics.- transcript topics: Polyploidy as a macro mutation and its continuum (auto- vs allo-polyploidy); Induction methods for polyploidy (Colchicine, chemical induction, DH breeding, triploidy, shocks); Gigas effect and biomass/bioproduct implications; Green bioeconomy: crops, biomass, and biofuels; Blue bioeconomy: triploid fish and polyploid algae; White bioeconomy: polyploid microbes in bioprocessing QC Summary:- factual score: 10/10- metadata score: 10/10- supported core claims: 6- claims flagged for review: 0- metadata checks passed: 4- metadata issues found: 0 Metadata Audited:- article_doi- article_title- article_journal- license Factual Items Audited:- Polyploidy is a macromut...

6/5/26 • 24:26

Sarabia Olivera L et al., PNAS - A perspective that surveys how diverse stresses trigger whole‑genome doubling (polyploidy) across fungi, plants, and animals, outlines common cell‑cycle mechanisms that produce polyploid cells, and evaluates the beneficial and detrimental consequences for genomes, cells, tissues, and applied contexts. Key terms: polyploidy, endocycles, oxidative stress, genome instability, regeneration. Study Highlights:The authors review evidence that many stresses — including temperature extremes, pharmacological agents, genotoxic insults, nutrient changes, infection, cell loss, and ROS — promote polyploidy across fungi, plants, and animals. Mechanistically, these stresses commonly act by perturbing the mitotic cell cycle via mitotic bypass, endoreplication, or failed cytokinesis. Polyploidy can enable tissue regeneration and buffer genomes but also increases genome instability, aneuploidy, and altered tissue function. Determining when polyploidy is adaptive versus harmful is presented as a key research priority for medicine and agriculture. Conclusion:Stress commonly induces polyploidy through conserved cell‑cycle alterations; its effects are context dependent, offering short‑term resilience or regeneration but often promoting genomic instability and long‑term functional costs, motivating cross‑discipline studies to understand mechanisms and applications. Music:Enjoy the music based on this article at the end of the episode. Article title:Growth under pressure: The pros and cons of polyploidy induced by stress First author:Sarabia Olivera L Journal:PNAS DOI:10.1073/pnas.2522063123 Reference:Sarabia Olivera L, Belato PB, Silva J, Selmecki A, Fox DT, Roeder AHK. Growth under pressure: The pros and cons of polyploidy induced by stress. PNAS. 2026;123(22):e2522063123. doi:10.1073/pnas.2522063123 License:This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support:Base by Base – Stripe donations: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 Official website https://basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/growth-under-pressure-polyploidy-stress QC:This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-06-04. QC Scope:- article metadata and core scientific claims from the narration- excludes analogies, intro/outro, and music- transcript coverage: Audited the transcript sections describing (1) diverse stress triggers and cell-cycle bypass mechanisms leading to polyploidy, (2) ROS as a unifying stress signal, (3) consequences at genome, cellular, and tissue levels, and (4) implications for therapy and agriculture; compared with the canonical article.- transcript topics: Stress-induced polyploidy triggers; Mitotic bypass and cytokinesis failure; ROS signaling and DNA damage response; Genomic instability and aneuploidy; Tissue regeneration vs senescence; Clinical and agricultural implications QC Summary:- factual score: 10/10- metadata score: 10/10- supported core claims: 6- claims flagged for review: 0- metadata checks passed: 4- metadata issues found: 0 Metadata Audited:- article_doi- article_title- article_journal- license Factual Items Audited:- Transcript describes diverse stresses triggering polyploidy (temperature, pharmacological, genotoxic, nutrient, infection, tissue loss).- ROS accumulation is presented as a universal master switch driving polyploidy.- Polyploi...

6/4/26 • 24:49

Haycocks JRJ et al., PNAS - This episode examines the discovery of CisR, a small RNA produced from the 3’UTR of prtV in Vibrio cholerae, which posttranscriptionally represses the CTXϕ-encoded cep mRNA via Hfq-mediated base-pairing. CisR accumulation is controlled by HapR and CRP and processed by RNase E, linking quorum sensing and carbon status to phage activation. We discuss the experimental evidence showing CisR lowers Cep protein levels and limits CTXϕ production under induction conditions. Key terms: small RNA, CTXϕ, Vibrio cholerae, Hfq, quorum sensing. Study Highlights:Researchers identified CisR as a ~50-nt sRNA derived from the 3’UTR of prtV that requires RNase E for processing and Hfq for stability and action. RIL-seq and reporter assays show CisR base-pairs with the cep mRNA ribosome binding site to inhibit translation, and deletion or overexpression of cisR respectively increases or decreases Cep levels and extracellular CTXϕ DNA after induction. Transcription of the vca0224-prtV-cisR operon is directly activated by HapR and CRP, linking CisR to quorum sensing and carbon catabolite signals. The work positions a core-genome sRNA as a posttranscriptional regulator that modulates a horizontally acquired phage life cycle. Conclusion:CisR is a 3’UTR-derived sRNA that integrates cell-density and metabolic signals to repress CTXϕ coat protein production via Hfq-dependent base-pairing with cep, thereby limiting phage production under stress and coordinating phage activation with host physiology. Music:Enjoy the music based on this article at the end of the episode. Article title:A 3’UTR-derived small RNA modulates the life cycle of the cholera toxin–encoding filamentous phage, CTXϕ First author:Haycocks JRJ Journal:PNAS DOI:10.1073/pnas.2535142123 Reference:Haycocks JRJ, O’Driscoll E, Sprenger M, Thriene K, Jung E-M, Siemers M, Lippegaus A, Krautwurst S, Grainger DC, Papenfort K. A 3’UTR-derived small RNA modulates the life cycle of the cholera toxin–encoding filamentous phage, CTXϕ. PNAS. 2026;123(23):e2535142123. doi:10.1073/pnas.2535142123 License:This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support:Base by Base – Stripe donations: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 Official website https://basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/cisr-controls-ctxphi-life-cycle QC:This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-06-03. QC Scope:- article metadata and core scientific claims from the narration- excludes analogies, intro/outro, and music- transcript coverage: Substantively audited the transcript sections describing CisR origin, CisR-cep interaction, HapR/CRP regulation, RIL-seq mapping, and functional impact on CTXϕ production under induction conditions.- transcript topics: CTXϕ life cycle and filamentous phage biology; CisR discovery from prtV 3’UTR and RNase E processing; HFQ and RIL-seq methodology to map RNA interactions; CisR-cep base-pairing and translational repression; HapR and CRP regulation of prtV-cisR transcription; CisR impact on CTXϕ production during MMC induction QC Summary:- factual score: 10/10- metadata score: 10/10- supported core claims: 6- claims flagged for review: 0- metadata checks passed: 4- metadata issues found: 0 Metadata Audited:- article_doi- article_title- article_journal- license Factual Items Audited:- CisR is produced from the 3’...

6/3/26 • 23:10