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 [Ca²⁺]_cyt increases (OICI_cyt), salt stress-induced [Ca²⁺]_cyt increases (SICI_cyt) and the associated growth phenotype in Arabidopsis osca1 (reduced hyperosmolality-induced [Ca²⁺]_cyt 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 Ca²⁺ 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_cyt and SICI_cyt, 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_cyt and SICI_cyt, 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.

干旱和盐分是严重影响植物生长发育以及作物生产的两大非生物胁迫。先前的一项研究表明，OsOSCA1.4是 11 种水稻OSCA ( OsOSCAs ) 之一，可补充高渗性诱导的 [Ca ²⁺ ]细胞_色素增加 (OICI _cyt )、盐胁迫诱导的 [Ca ²⁺ ]_细胞色素增加 (SICI _cyt ) 和拟南芥osca1中相关的生长表型（降低高渗性诱导的 [Ca ^{2 +} ]_细胞色素增加 1）。在本研究中，除了OsOSCA2.3和OsOSCA4.1，我们生成了在 osca1 中过表达其他 8 个OsOSCA 的独立转基因系，以探索它们在高渗和盐胁迫下在渗透 Ca ²⁺信号传导、气孔运动、叶片水分流失和根系生长中的功能。与 OsOSCA1.4类似，在osca1中过表达OsOSCA1.1或OsOSCA2.2补充了 OICI cyt_和SICI _cyt，以及响应高渗和盐胁迫处理以及与干旱相关的叶片水分流失的气孔关闭和根生长。此外，OsOSCA1.2的过表达，osca1中的OsOSCA1.3或OsOSCA2.1恢复了 OICI _cyt和 SICI _cyt，而OsOSCA2.5或OsOSCA3.1的过表达则没有。此外，过表达这五个OsOSCA的osca1表现出各种非生物胁迫相关的生长表型。然而，OsOSCA2.4的过表达没有任何这些影响。这些结果表明，OsOSCA家族的多个成员在渗透传感中具有冗余功能，在压力适应中具有不同的作用。