2025-07-09 中国科学院(CAS)
HDA9 Mediates Phot1 Acetylation-Phosphorylation Homeostasis to Regulate Plant Phototropism. (Imaged by LIU Xuncheng et al)
<関連情報>
- https://english.cas.cn/newsroom/research_news/life/202507/t20250710_1047143.shtml
- https://www.sciencedirect.com/science/article/pii/S2590346225001865
ヒストン脱アセチル化酵素9が植物の光応答を微調整するためにフォトトロピン1のアセチル化ダイナミクスを調節する Histone Deacetylase 9 Modulates Phototropin 1 Acetylation Dynamics to Fine-Tune Phototropic Responses in Plants
Minting Liang, Shulin Deng, Yi Zhang, Jingyuan Guo, Zhiyang Lie, Yongyi Yang, Guangyi Dai, Xuncheng Liu
Plant Communications Available online: 21 June 2025
DOI:https://doi.org/10.1016/j.xplc.2025.101424
Highlights:
- An regulator between a light signal and phototropin 1 was identified.
- Modification via lysine acetylation can regulate the activity of phot1 kinase.
- Acetylation homeostasis controls light-triggered phot1 phosphorylation.
- The acetylation dynamics of phot1 are modulated by the histone deacetylase HDA9.
Abstract
Phototropism is essential for optimizing plant growth and development, with the blue light receptor phototropin 1 (phot1) acting as the primary photoreceptor. Although downstream components of phot1-mediated phototropic signaling have been extensively studied, the upstream regulatory mechanisms controlling phot1 activity remain elusive. Here, we demonstrate that lysine acetylation dynamically modifies phot1 under both dark and light conditions. Functional analyses using site-directed mutagenesis of acetylated lysines revealed that acetylation regulates phot1’ s light-induced autophosphorylation and kinase activity. Genetic screening of histone deacetylase (HDAC) mutants identified HDA9 as a key regulator of phototropism, which physically interacts with phot1 to modulate its acetylation and phosphorylation levels in response to light. Importantly, we pinpointed K636 as the critical acetylation site targeted by HDA9, linking deacetylation to phot1 activation. Our findings establish a regulatory paradigm in which HDA9-mediated deacetylation fine-tunes phot1 phosphorylation dynamics to control phototropic responses. This acetylation-phosphorylation crosstalk suggests to be evolutionarily conserved, underscoring its broad significance in light signaling. Our study provides mechanistic insights into how antagonistic post-translational modifications precisely regulate photoreceptor sensitivity and signal transduction in plants.
