Functional Research Of Receptor Like Kinase OsRLCK77in Rice (Oryza Sativa)

Membrane-anchored receptor-like protein kinases (RLKs) recognize extracellular signals at the cell surface and activate the downstream signaling pathway by phosphorylating specific target proteins. RLKs play important roles in plant growth, development and responses to environ-mental stresses. Receptor-like cytoplasmic kinases (RLCKs) in plants belong to the super family of receptor-like kinases (RLKs). These proteins show homology to RLKs in kinase domain but lack the transmembrane domain. Some of the functionally characterized RLCKs from plants have been shown to play roles in development and stress responses.Here we have identified a rice T-DNA insertion mutant for reduced organ size. OsRLCK77is predicted to encode an RLCK. Loss of function of OsRLCK77produced dwarf plants. OsRLCK77was predicted to be a member of the receptor-like kinase (RLK) family. Domain searches using PFAM and SMART showed that OsRLCK77protein with three domains:an N-terminal signal peptide (1-46amino acids), a transmembrane domain (39-61) and a cytoplasmic kinase domain (163-434), was a cytoplasmic receptor like kinase (RLCK), but not showed which subfamily it was belonged to.We analyzed the receptor-like cytosolic kinase (RLCK) gene, OsRLCK77, whose expression was in all tissues including culm, leaf blades and sheaths, and young panicle. The arck77mutant showed lower sensitivity than the wild-type to salt. When we treated it by salt, drought, cold, the expression of OsRLCK77is decreased. These results indicate that OsRLCK77may plays important roles in salt and drought stress tolerance in rice.Rice is the most important food crops in our country and whole world. This study analysis the function of a plant receptor-like kinase (RLKs) gene OsRLCK77in rice, and provides a certain reference for rice yield and plant resistance against stresses. We believe that the study of the RLKs will get more and more in the future.