A pair of G‐type lectin receptor‐like kinases modulates nlp20‐mediated immune responses by coupling to the RLP23 receptor complex

• DOI: 10.1111/jipb.13449
• Publication Date: 2023-01-12T11:35:30Z
• Authors: Yazhou Bao; Yixin Li; Qin Chang; Rubin Chen; Weijie Wang; Qian Zhang; Shuxian Chen; Guangyuan Xu; Xiaodan Wang; Fuhao Cui; Daolong Dou; Xiangxiu Liang
• Keywords: C-type lectin; Flagellin; Immunoprecipitation

Plant cells recognize microbial patterns with the plasma-membrane-localized pattern-recognition receptors consisting mainly of receptor kinases (RKs) and receptor-like proteins (RLPs). RKs, such as bacterial flagellin FLS2, their downstream signaling components have been studied extensively. However, newly discovered regulatory RLP-mediated immune signaling, nlp20 RLP23, await identification. Unlike RLPs lack a cytoplasmic kinase domain, instead recruiting (RLKs) BAK1 SOBIR1. SOBIR1 specifically works an adapter for immunity. To identify new regulators we looked SOBIR1-binding (SBPs) in Arabidopsis thaliana using protein immunoprecipitation mass spectrometry, identifying two G-type lectin RLKs, SBP1 SBP2, that physically interacted SBP2 showed high sequence similarity, were tandemly repeated on chromosome 4, also both RLP23 BAK1. sbp1 sbp2 double mutants obtained via CRISPR-Cas9 gene editing severely impaired nlp20-induced reactive oxygen species burst, mitogen-activated (MAPK) activation, defense expression, but normal flg22-induced responses. We regulated immunity activity-independent manner. Furthermore, RLP23-BAK1 interaction, although not FLS2-BAK1 was significantly reduced sbp2. This study identified SBPs complex may modulate RLP23-mediated by positively regulating interaction between co-receptor.