Department of Biology, Copenhagen University Copenhagen, Denmark.
Front Plant Sci. 2012 Aug 24;3:209. doi: 10.3389/fpls.2012.00209. eCollection 2012.
Receptor-like kinases (RLKs) are surface localized, transmembrane receptors comprising a large family of well-studied kinases. RLKs signal through their transmembrane and juxtamembrane domains with the aid of various interacting partners and downstream components. The N-terminal extracellular domain defines ligand specificity, and RLK families are sub-classed according to this domain. The most studied of these subfamilies include those with (1) leucine-rich repeat (LRR) domains, (2) LysM domains (LYM), and (3) the Catharanthus roseus RLK1-like (CrRLK1L) domain. These proteins recognize distinct ligands of microbial origin or ligands derived from intracellular protein/carbohydrate signals. For example, the pattern-recognition receptor (PRR) AtFLS2 recognizes flg22 from flagellin, and the PRR AtEFR recognizes elf18 from elongation factor (EF-Tu). Upon binding of their cognate ligands, the aforementioned RLKs activate generic immune responses termed pattern-triggered immunity (PTI). RLKs can form complexes with other family members and engage a variety of intracellular signaling components and regulatory pathways upon stimulation. This review focuses on interesting new data about how these receptors form protein complexes to exert their function.
受体样激酶（RLKs）是位于表面的跨膜受体，包含一个经过充分研究的激酶大家族。RLKs 通过其跨膜和近膜结构域与各种相互作用的伙伴和下游成分进行信号传递。N 端细胞外结构域定义了配体特异性，RLK 家族根据该结构域进行亚分类。这些亚家族中研究最多的包括具有（1）富含亮氨酸重复（LRR）结构域、（2）LysM 结构域（LYM）和（3）长春花 RLK1 样（CrRLK1L）结构域的那些。这些蛋白质识别来自微生物或源自细胞内蛋白质/碳水化合物信号的独特配体。例如，模式识别受体（PRR）AtFLS2 识别来自鞭毛蛋白的 flg22，而 PRR AtEFR 识别来自延伸因子（EF-Tu）的 elf18。在结合其同源配体后，上述 RLKs 激活被称为模式触发免疫（PTI）的通用免疫反应。RLKs 可以与其他家族成员形成复合物，并在受到刺激时与各种细胞内信号成分和调节途径相互作用。这篇综述重点介绍了有关这些受体如何形成蛋白质复合物以发挥其功能的有趣新数据。
