Zhai Yuanjun, Wen Zhaohong, Fang Wenqi, Wang Yinxing, Xi Chao, Liu Jin, Zhao Heping, Wang Yingdian, Han Shengcheng
Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing, 100875, People's Republic of China.
Transgenic Res. 2021 Dec;30(6):811-820. doi: 10.1007/s11248-021-00270-x. Epub 2021 Jun 19.
Drought and salt are two major abiotic stresses that severely impact plant growth and development, as well as crop production. A previous study showed that OsOSCA1.4, one of eleven rice OSCAs (OsOSCAs), complements hyperosmolality-induced [Ca] increases (OICI), salt stress-induced [Ca] increases (SICI) and the associated growth phenotype in Arabidopsis osca1 (reduced hyperosmolality-induced [Ca] increase 1). In this study, Except for OsOSCA2.3 and OsOSCA4.1, we generated independent transgenic lines overexpressing eight other OsOSCAs in the osca1 to explore their functions in osmotic Ca signalling, stomatal movement, leaf water loss, and root growth in response to hyperosmolality and salt stress. Similar to OsOSCA1.4, overexpression of OsOSCA1.1 or OsOSCA2.2 in osca1 complemented OICI and SICI, as well as stomatal closure and root growth in response to hyperosmolality and salt stress treatments, and drought-related leaf water loss. In addition, overexpression of OsOSCA1.2, OsOSCA1.3 or OsOSCA2.1 in osca1 restored OICI and SICI, whereas overexpression of OsOSCA2.5 or OsOSCA3.1 did not. Moreover, osca1 overexpressing these five OsOSCAs exhibited various abiotic stress-associated growth phenotypes. However, overexpression of OsOSCA2.4 did not have any of these effects. These results indicated that multiple members of the OsOSCA family have redundant functions in osmotic sensing and diverse roles in stress adaption.
干旱和盐胁迫是严重影响植物生长发育以及作物产量的两大主要非生物胁迫因素。先前的一项研究表明，水稻11个OSCA（OsOSCAs）之一的OsOSCA1.4能够互补拟南芥osca1中高渗诱导的[Ca]升高（OICI）、盐胁迫诱导的[Ca]升高（SICI）以及相关的生长表型（高渗诱导的[Ca]升高降低1）。在本研究中，除了OsOSCA2.3和OsOSCA4.1，我们在osca1中生成了过表达其他8个OsOSCAs的独立转基因株系，以探究它们在渗透Ca信号传导、气孔运动、叶片水分流失以及根系生长对高渗和盐胁迫响应中的功能。与OsOSCA1.4相似，在osca1中过表达OsOSCA1.1或OsOSCA2.2可互补OICI和SICI，以及对高渗和盐胁迫处理的气孔关闭和根系生长，还有与干旱相关的叶片水分流失。此外，在osca1中过表达OsOSCA1.2、OsOSCA1.3或OsOSCA2.1可恢复OICI和SICI，而过表达OsOSCA2.5或OsOSCA3.1则不能。而且，过表达这5个OsOSCAs的osca1表现出各种与非生物胁迫相关的生长表型。然而，过表达OsOSCA2.4没有这些任何效应。这些结果表明，OsOSCA家族的多个成员在渗透感知中具有冗余功能，在胁迫适应中具有不同作用。
