Conservation of Chitin-Induced MAPK Signaling Pathways in Rice and Arabidopsis

• DOI: 10.1093/pcp/pcx042
• Publication Date: 2017-03-21T12:29:33Z
• Authors: Kenta Yamada; Koji Yamaguchi; Satomi Yoshimura; Akira Terauchi; Tsutomu Kawasaki
• Keywords: Bimolecular fluorescence complementation; MAPK cascade

Perception of microbe-associated molecular patterns (MAMPs) including chitin by pattern recognition receptors (PRRs) rapidly induces activation mitogen-activated protein kinase (MAPK) cascades. However, how PRRs transmit immune signals to the MAPK cascade is largely unknown. Recently, Arabidopsis receptor-like cytoplasmic PBL27 has been reported activate MAPKs through phosphorylation AtMAPKKK5 in signaling pathway. In this study, we found that OsRLCK185, a rice ortholog PBL27, regulates chitin-induced similar fashion rice. Upon perception, OsRLCK185 phosphorylated OsCERK1, component receptor complex. interacted with OsMAPKKK11 and OsMAPKKK18, orthologs AtMAPKKK5, yeast two-hybrid assays. Silencing both OsMAPKKK18 significantly reduced OsMPK3 OsMPK6. Expression levels were much higher than cells, which was consistent fact Osmapkkk11 single mutation did not affect activation. This result suggested plays more important role The bimolecular fluorescence complementation (BiFC) experiment indicated at plasma membrane planta. vitro experiments showed directly phosphorylates OsMAPKKK18. Furthermore, MAPKK OsMKK4, upstream OsMPK3/6. These results connects consisting OsMAPKKK18-OsMKK4-OsMPK3/6. Our data revealed regulated common homologous elements.