HDA19-mediated deacetylation of histone H3.3 at lysines 27 and 36 regulates plant sensitivity to salt stress

• 成果类型: Article
• 署名作者: Kotnik, Florian; Ueda, Minoru; Ito, Akihiro; Ishida, Junko; Takahashi, Satoshi; Sakai, Katsuyuki; Takagi, Hiroshi; Seidel, Julian; Abe, Takahiro; Eirich, Jurgen; Takahashi, Shunji; Schwarzer, Dirk; Seki, Motoaki; Finkemeier, Iris
• 署名单位: University of Munster; RIKEN; Tokyo University of Pharmacy & Life Sciences; RIKEN; RIKEN; Eberhard Karls University of Tubingen; Yokohama City University; Saitama University
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.2534315123
• 发表日期: 2026-07-21
• 页码: e2534315123
• 关键词: histone deacetylase; histone acetylation; salinity stress response; arabidopsis; late embryogenesis abundant proteins; abscisic-acid; PROTEIN LEA7; class-i; gene; embryogenesis; acetylation; expression; INTERACT; complexes; variants

摘要

Plants survive extreme environments through rapid chromatin reprogramming, yet the epigenetic marks that confer stress resilience remain poorly understood. Histone deacetylase HDA19 is a key epigenetic regulator in Arabidopsis, and hda19-deficient mutants display tolerance to multiple abiotic stresses, including drought, heat, and salinity. Using lysine acetylome profiling, we identified a noncanonical K27/K36 diacetylation mark on histone H3.3, among nine H3 variants, as a specific substrate of HDA19. Under salinity stress, this mark decreased in wild-type plants but increased in hda19 mutants, while other known H3 modifications were similarly affected in both genotypes. Mimicking constitutive diacetylation of H3.3K27/K36 through lysine-to-glutamine substitutions promoted accumulation of stress-responsive late embryogenesis abundant (LEA) proteins and conferred salinity tolerance in seedlings, phenocopying hda19 mutants. Furthermore, generating the lea7-1/lea29-1/rab18-1 triple mutant abolished hda19-dependent salinity tolerance, confirming the LEA proteins' role downstream of HDA19. Our findings demonstrate that H3.3K27/K36 diacetylation, modulated by HDA19, drives LEA protein accumulation and enables plants to withstand environmental stress, revealing a core mechanism of plant stress resilience.