Essential angiosperm-specific subunits of HDA19 histone deacetylase complexes in Arabidopsis

作者：Na Liu, Jiaxin Li, Dan‐Yang Yuan, Yin‐Na Su, Pei Zhang, Qi Wang, Xiao‐Min Su, Lin Li, Haitao Li, She Chen, Xin‐Jian He · 发表于：The EMBO Journal · 年份：2025 · DOI：10.1038/s44318-025-00445-w · 被引用次数：8 · 研究领域：Plant Molecular Biology Research、Histone Deacetylase Inhibitors Research、Plant Gene Expression Analysis

Although the Arabidopsis thaliana RPD3-type histone deacetylase HDA19 and its close homolog HDA6 participate in SIN3-type histone deacetylase complexes, they display distinct biological roles, with the reason for these differences being poorly understood. This study identifies three angiosperm-specific HDA19-interacting homologous proteins, termed HDIP1, HDIP2, and HDIP3 (HDIP1/2/3). These proteins interact with HDA19 and other conserved histone deacetylase complex components, leading to the formation of HDA19-containing SIN3-type complexes, while they are not involved in the formation of HDA6-containing complexes. While mutants of conserved SIN3-type complex components show phenotypes divergent from the hda19 mutant, the hdip1/2/3 mutant closely phenocopies the hda19 mutant with respect to development, abscisic acid response, and drought stress tolerance. Genomic and transcriptomic analyses indicate that HDIP1/2/3 and HDA19 co-occupy chromatin and jointly repress gene transcription, especially for stress-related genes. An α-helix motif within HDIP1 has the capacity to bind to nucleosomes and architectural DNA, and is required for its function in Arabidopsis plants. These findings suggest that the angiosperm SIN3-type complexes have evolved to include additional subunits for the precise regulation of histone deacetylation and gene transcription.