The 30th International Conference on Arabidopsis Research (ICAR 2019)

605 / 2019-04-22 15:28:01

OsOSCA1.4 Perceives Osmotic Stress Signals triggered by Hyperosmolality- and Salt-stresses in Rice.

abiotic stress；rice；calcium

Plenary track > Signal Transduction

Drought and salt stresses are the major abiotic constraints for plant growth and development, and crops production worldwide, and the first common phase of drought and salt stresses are hyperosmotic stress. It is known that both of hyperosmolality- and salt-stress induce cytosolic calcium increases (OICIcyt and SICIcyt) within seconds, and the mechanism on plants distinguishing hyperosmotic stress signal induced by hyperosmolality- and salt-stress remains enigmatic. Here, we have cloned 10 rice OSCA homologous (named as OsOSCAs) and used a functional screening assay in mammalian cells to characterize OsOSCA1.4 mediating OICIcyt and SICIcyt in HEK293 cells. OsOSCA1.4 encodes a plasma membrane-localized and calcium-permeable nonselective cation channel, which perceives hyperosmotic signal induced by hyperosmolality- and salt-stress to mediate an inward current. However, ososca1.4 displayed an attenuated OICIcyt in lateral root cells, disrupted stomata closure and resistance in leaves in response to hyperosmolality stress, but not to salt stress in rice. RNA-Seq analysis revealed some OsOSCA1.4-mediated differentially-expressed genes response to hyperosmolality- or/and salt-stress. These results suggested that OsOSCA1.4 functions as a putative osmosensor perceiving hyperosmotic stress signal induced by hyperosmolality-stress, but not salt-stress, providing insight for dissecting different abiotic stresses signal transduction in plants.