Base by Base

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:
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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 framework implemented in BEAST 2 for jointly estimating time-scaled phylogenies and cell population parameters using sequential, ordered CRISPR edits (DNA Tape
- The model uses per-tape clock rates and insertion probabilities to describe editing dynamics.
- Felsenstein pruning is used for likelihood calculation across the phylogeny with tape data.
- HEK293T monoclonal expansion dataset (~25 days) used to validate editing dynamics and growth rates; observed CAT insertions around 16% and GCG around ≤1%.
- Clock rates around 0.15 d^-1 on most tapes, equating to roughly 4 edits per tape over the experiment duration.
- SciPhy produced more accurate time-calibrated trees and differentiated branch lengths compared to UPGMA on both simulated and real data.

QC result: Pass.

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 coalignment; onset at ~10 mM (homologous tweezers) vs ~20 mM (heterologous).
- Interaxial separation and adsorption parameters: R ≈ 27.7–27.9 Å; f2 ≈ 0.991–0.999, indicating dominant major-groove adsorption.
- Longer duplexes (68 bp) coalign less due to entropic penalties and increased conformational space.

QC result: Pass.

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 biases modulate GC3+ hotspot strength
- Leading vs lagging strand replication affects context biases; biases stronger when purine templates the leading strand
- Regional GC-content up to 1,000 bp away contributes to mutational bias; AT-rich regions show differential effects depending on repair status (MMR/proofreading)

QC result: Pass.

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 Opus 4, Claude 3.7 Sonnet, Gemini 2.5 Pro, Gemini 2.0 Flash
- Cohorts studied: Kawasaki disease (KD) vs MIS-C, active tuberculosis (TB) vs symptomatic controls, ME/CFS vs sedentary controls
- Two tasks were used: (1) feature selection to nominate 200 genes; (2) end-to-end classifier construction from cfRNA count matrices
- LLM-nominated panels outperformed random panels; TB panels matched/exceeded DGE; KD and ME/CFS panels trailed DGE in predictive performance
- End-to-end classifiers were feasible for some models; OpenAI o3 and Claude Opus 4 completed end-to-end pipelines
- OpenAI o3 achieved ~86.7% mean accuracy for KD vs MIS-C end-to-end; TB: ~76.3–77.6%; ME/CFS showed limited gains

QC result: Pass.

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:
- tNGS detected rifampicin resistance in 159/234 samples (68%), with 96 of these carrying the rpoB I491F mutation
- Rv0678 mutations (bedaquiline/clofazimine resistance) found in 87 strains, present in 55% of RR isolates and commonly co-occurring with rpoB I491F
- Routine diagnostics under-classified resistance: Xpert Ultra detected RR in about 32% of samples; LPA and MGIT pDST around 20%
- tNGS-informed treatment changes occurred in 53% (31/59) of patients with complete clinical data, with 88% (52/59) treatment success
- Transmission of BDQ-resistant strains suggested; only one of 48 patients with prior TB exposure had bedaquiline exposure

QC result: Pass.

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 Ces1c and Ces1d associated with post-infusion interval
- Ces1 enzymes metabolize cocaine and influence duration/intensity of effects
- Trak2 is the rat ortholog of human TRAK2 and overlaps human CUD GWAS signals
- Rasd2 and Gnas show brain-region eQTLs related to cocaine response
- LgA PC1 addiction-like behavior explains ~55% of variance with SNP-based heritability up to 0.16

QC result: Pass.

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

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-early genes
- Pre-early gene products drive host DNA degradation leading to a mutual destruction outcome
- Bas33 is daunorubicin-sensitive, whereas the model Tevenvirinae phage T4 shows resistance to daunorubicin
- A1 and A2 pre-early genes reside in the first 9% of Bas33 genome and are involved in host takeover; transcription of these genes is affected by daunorubicin
- EcoP1_I RM system provides strong synergy with daunorubicin, with eight recognition sites in the pre-early region contributing to protection
- Synergy between daunorubicin and RM systems can shift outcomes from Abi-like cell death to population survival

QC result: Pass.

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, impairing Skp2 binding.

QC result: Pass.

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:
- Targeting activated HSCs via FAP expression using CAR-M strategy
- CD163-targeted LNPs deliver FAPCAR mRNA to hepatic macrophages in situ
- CAR design includes CD3ζ signaling and CD28 costimulation
- In vitro CAR-M show markedly increased phagocytosis and cytotoxicity toward FAP+ cells
- In vivo mouse models show reduced hydroxyproline, ALT, ECM deposition and improved histology
- scRNA-seq reveals expansion of MMP12+ scar-associated macrophages (SAM)

QC result: Pass.