Molecular analysis of Arabidopsis thaliana LRR receptor protein kinases (LRR-RLK) implicated in pathogen defense

富含亮氨酸重复序列（LRR）蛋白（LRRP）和LRR受体样激酶（LRR-RLK）参与植物抗病性的激活。这些蛋白质被认为与迄今未知的相互作用蛋白质形成大的信号感知复合物。由于在真核生物中的信号通路的编码组件的基因往往被发现转录上调相应的刺激，我们将利用这一点来确定新的LRR-RLK和LRRP编码基因可能参与疾病抗性。为了分析和分离介导植物防御反应激活的信号感知复合物，我们提出了以下策略：拟南芥Col-O植物将感染无毒的细菌，卵菌和真菌病原体，也将渗透与植物防御反应的选举人。来自受感染植物的RNA将用于使用基因特异性引物（来自基因组数据库）的RT-PCR测定或用于LRRP/LRR-RLK-芯片上的cDNA微阵列测定。所选基因将根据其在植物防御信号传导中的功能进行表征（通过T-DNA插入或RNA干扰进行基因失活，随后在感染测定中分析突变体）。生物化学表征将涉及分离与标记的LRRP/LRR-RLK诱饵蛋白相互作用的蛋白，并通过胰蛋白酶片段化/MALDI-TOF光谱法鉴定相互作用的蛋白。

Leucine-rich repeat (LRR) proteins (LRRP) and LRR receptor-like kinases (LRR-RLK) have been implicated in the acivation of plant disease resistance. These proteins are believed to form large signal perception complexes with so far unknown interacting proteins. Since genes encoding components of signaling pathways in eukaryotes are often found to be transcriptionally up-regulated by the corresponding stimulus, we will exploit this to identify new LRR-RLK and LRRP-encoding genes potentially involved in disease restistance. To analyze and isolate signal perception complexes mediating the activation of plant defense responses we propose the following strategy: Arabidopsis thaliana Col-O plants will be infected with avirulent bacterial, oomycete, and fungal pathogens and will be also infiltrated with elecitors of plant defense reactions. RNA from infected plants will be used in RT-PCR assays with gene-specific primers (derived from the genomic database) or in cDNA microarray assays on LRRP/LRR-RLK-chips. Selected genes will be characterized with respect to their function in plant defense signaling (gene inactivation by T-DNA insertion or RNA interference and subsequent analysis of the mutants in infection assays). Biochemical characterization will involve isolation of interacting proteins with tagged LRRP/LRR-RLK bait-protein and identification of interacting proteins by tryptic fragmentation/MALDI-TOF spectroscopy.