Lian Na, Zhang Xinyuan, Wang Xinwei, Zhang Yu, Wu Xinyuan, Qian Hongping, He Qizouhong, Jing Yanping, Mao Tonglin, Lin Jinxing
State Key Laboratory of Tree Genetics and Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China.
State Key Laboratory of Plant Environmental Resilience, Department of Plant Sciences, College of Biological Sciences, China Agricultural University, Beijing 100193, China.
Sci Adv. 2025 Feb 14;11(7):eads3653. doi: 10.1126/sciadv.ads3653. Epub 2025 Feb 12.
Woody plants must acclimate to environmental stresses, including soil salinity, for proper growth and development. Microtubule reorganization supports plant survival in saline-rich soils, but the underlying molecular mechanism in tree species remains unclear. In this study, we identified a salinity stress response mechanism in hybrid poplar seedlings. This mechanism involves regulation of microtubule dynamics by the microtubule-associated protein PLASMA MEMBRANE-ASSOCIATED CATION BINDING PROTEIN 1a (PagPCaP1a). Salinity stress induced expression and phase separation of PagPCaP1a protein to form PagPCaP1a condensates in a calcium-dependent manner. The formation of PagPCaP1a condensates was partially driven by the VEEEKK motif within the carboxyl terminus of the protein, which rapidly depolymerizes microtubules under salinity stress. Our study reveals that the liquid-liquid phase separation of PagPCaP1a represents an additional regulatory layer for microtubule depolymerization, and we propose an effective strategy to manipulate the phase separation of PagPCaP1a to improve plant stress tolerance.
木本植物必须适应包括土壤盐分在内的环境胁迫，以实现正常生长和发育。微管重组有助于植物在盐分丰富的土壤中存活，但树种中潜在的分子机制仍不清楚。在本研究中，我们在杂种杨树幼苗中鉴定出一种盐胁迫响应机制。该机制涉及微管相关蛋白质膜相关阳离子结合蛋白1a（PagPCaP1a）对微管动力学的调节。盐胁迫以钙依赖的方式诱导PagPCaP1a蛋白的表达和相分离，形成PagPCaP1a凝聚物。PagPCaP1a凝聚物的形成部分由该蛋白羧基末端的VEEEKK基序驱动，该基序在盐胁迫下使微管迅速解聚。我们的研究表明，PagPCaP1a的液-液相分离代表了微管解聚的另一个调节层，并且我们提出了一种有效的策略来操纵PagPCaP1a的相分离以提高植物的胁迫耐受性。
