233: NuA3 structure reveals the mechanism of H3K14 acetylation

Shi W et al., Mechanistic insights into histone recognition and H3K14 acetylation by the NuA3 histone acetyltransferase complex - Cryo-EM structures of the yeast NuA3 complex show a composite histone tail binding cleft formed by Sas3 and Nto1 that dictates selective acetylation of H3K14. Key terms: NuA3, Sas3, Nto1, H3K14 acetylation, cryo-EM. Study Highlights:The six-subunit NuA3 complex was purified and shown to acetylate H3K14 preferentially on H3K4- or H3K36-trimethylated substrates. Cryo-EM maps of the apo, acetyl-CoA-bound, and acetyl-CoA plus H3 tail-bound states were determined at 3.7 Å, 3.1 Å, and 3.2 Å resolution, respectively. The H3 tail binding cleft is formed cooperatively by the catalytic Sas3 MYST domain and the Nto1 PZP region, with a hydrophobic pocket engaging H3 residues 9–12 and a network of polar contacts around Gly13–Ala15 that confer site specificity. Mutations predicted to disrupt contacts (L369R, N354A, E452Q) impair or abolish HAT activity in vitro and reduce H3K14 acetylation in yeast. Binding of acetyl-CoA induces conformational shifts in a histone-engaging loop and a CoA-engaging helix that likely position catalytic residues for transfer Conclusion:The structures define how cooperative recognition by Sas3 and Nto1 and local conformational changes confer high specificity for H3K14 acetylation and suggest conservation of this recognition mode in human homologs Music:Enjoy the music based on this article at the end of the episode. First author:Shi W Journal:Mechanistic insights into histone recognition and H3K14 acetylation by the NuA3 histone acetyltransferase complex DOI:10.1038/s41467-025-67049-0 Reference:Shi W., Zhao L., Wang Y., Zhang Y., Liu S., Wang Y., Kornberg R. D., Zhang H. Mechanistic insights into histone recognition and H3K14 acetylation by the NuA3 histone acetyltransferase complex. Nat Commun (2025). https://doi.org/10.1038/s41467-025-67049-0 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/nua3-h3k14-structure QC:This episode was checked against the original article PDF and publication metadata for the episode release published on 2025-12-19. 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 NuA3 structure-function findings: complex composition, cooperative histone tail binding cleft, acetyl-CoA–induced conformational priming, substrate specificity with Gly13, mutational evidence (L369R, N354A, E452Q), recruitment marks (H3K4me3/H3K36me3), and cross-species conservation- transcript topics: NuA3 subunit composition; Cooperative H3 tail binding cleft formed by Sas3 and Nto1; Acetyl-CoA binding and conformational priming; Substrate specificity and Gly13 determinant; Mutational effects: L369R, N354A, E452Q; Recruitment marks: H3K4me3 and H3K36me3 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:- NuA3 is a six-subunit histone acetyltransferase complex (Sas3, Nto1, Yng1, Eaf6, Taf14, Pdp3).- NuA3 acetylates histone H3K14 and recruitment...