SERKs serve as co-receptors for SYR1 to trigger systemin-mediated defense responses in tomato  

作　　者：Hyewon Cho Dain Seo Minsoo Kim Bo Eun Nam Soyoun Ahn Minju Kang Geul Bang Choon-Tak Kwon Youngsung Joo Eunkyoo Oh 

机构地区：[1]Department of Life Sciences,Korea University,Seoul 02841,Korea [2]Research,Institute of Basic Sciences,Seoul National University,Seoul 08826,Korea [3]School of Biological Sciences,Seoul National University,Seoul 08826,Korea [4]Digital Omics Research Center,Ochang Institute of Biological and Environmental Science,Korea Basic Science Institute,Cheongju 28119,Korea [5]Department of Smart Farm Science,Kyung Hee University,Yongin 17104,Korea

出　　处：《Journal of Integrative Plant Biology》2024年第10期2273-2287,共15页植物学报（英文版）

基　　金：supported by the National Research Foundation of Korea Grant funded by the Korean Government (NRF-2022R1A4A3024451 and NRF2023R1A2C3002386);a grant from Korea University。

摘　　要：Systemin, the first peptide hormone identified in plants, was initially isolated from tomato(Solanum lycopersicum) leaves. Systemin mediates local and systemic wound-induced defense responses in plants, conferring resistance to necrotrophic fungi and herbivorous insects. Systemin is recognized by the leucine-rich-repeat receptor-like kinase(LRRRLK) receptor SYSTEMIN RECEPTOR1(SYR1), but how the systemin recognition signal is transduced to intracellular signaling pathways to trigger defense responses is poorly understood. Here, we demonstrate that SERK family LRR-RLKs function as coreceptors for SYR1 to mediate systemin signal transduction in tomato. By using chemical genetic approaches coupled with engineered receptors, we revealed that the association of the cytoplasmic kinase domains of SYR1 with SERKs leads to their mutual trans-phosphorylation and the activation of SYR1, which in turn induces a wide range of defense responses. Systemin stimulates the association between SYR1 and all tomato SERKs(SlSERK1,SlSERK3A, and SlSERK3B). The resulting SYR1-SlSERK heteromeric complexes trigger the phosphorylation of TOMATO PROTEIN KINASE 1B(TPK1b), a receptor-like cytoplasmic kinase that positively regulates systemin responses. Additionally,upon association with SYR1, SlSERKs are cleaved by the Pseudomonas syringae effector HopB1, further supporting the finding that SlSERKs are activated by systemin-bound SYR1. Finally, genetic analysis using Slserk mutants showed that SlSERKs are essential for systemin-mediated defense responses. Collectively, these findings demonstrate that the systeminmediated association of SYR1 and SlSERKs activates defense responses against herbivorous insects.

关 键 词：LRR-RLK PEPTIDE SERK SYR1 SYSTEMIN 

分 类 号：S641.2[农业科学—蔬菜学]