Functional analysis of Arabidopsis LysM-RLKs and related kinases in chitin perception and defense signaling

在植物中，许多关键过程，如发育、生殖、激素信号和对病原体的防御等，都受受体样激酶(RLKs)的调控。越来越多的证据表明，植物跨膜受体是高度复杂的异构体，由许多不同的RLK和受体样胞浆激动酶(RLCK)组成。在模式植物拟南芥中，质膜定位的LysM-RLK CERK1介导了对真菌PAMP甲壳素的感知(以及一个尚未识别的细菌危险信号)，并随后激活了植物防御。本项目的重点是另外两个LysM-RLKs的功能分析，LysM-RLK3&4和一个新的RLCK，CIR1，我们确定它们是CERK1潜在的异构体受体复合体伙伴。我们建议分析LysM-RLK3、LysM-RLK4和CIR1在几丁质信号和其他CERK1介导的过程中的作用，验证它们与CERK1在植物中的相互作用，并研究它们在激发子处理和病原体攻击中的亚细胞定位行为。我们期望对PAMP诱导的受体复合体的形成、信号转导和脱敏以及病原体诱导的细胞极化和动态蛋白质运输的新的机制见解将扩展我们对植物先天免疫的理解。

In plants, many key processes such as development, reproduction, hormone signaling and defense against pathogens are regulated by receptor-like kinases (RLKs). It is becoming increasingly evident that plant transmembrane receptors are highly complex heteromers, consisting of a number of different RLKs as well as receptor-like cytoplasmic kinases (RLCKs). In the model plant Arabidopsis thaliana, the plasma-membrane localised LysM-RLK CERK1 mediates perception of the fungal PAMP chitin (and a yet unidentified bacterial danger signal) and subsequent activation of plant defence. This project focuses on the functional analysis of two other LysM-RLKs, LysM-RLK3 & 4, and a novel RLCK, CIR1, which we identified as potential heteromeric receptor complex partners of CERK1. We propose to analyse the role of LysM-RLK3, LysM-RLK4 and CIR1 in chitin signalling and other CERK1-mediated processes, to validate their interaction with CERK1 in planta and to study their subcellular localisation behaviour in response to elicitor treatment and pathogen attack. We expect novel mechanistic insights into PAMP-induced receptor complex formation, signalling and desensitization, as well as pathogen-induced cell polarization and dynamic protein trafficking that will extend our understanding of plant innate immunity.