Calcium signalling induced by MAMPs (Microbe-associated molecular patterns) in Arabidopis thaliana

钙离子是一种普遍存在的信号转导第二信使。与叶中的flg 22一样，来自梨形孢的细胞壁提取物（CWE）模仿真菌的生长促进作用，诱导根中细胞质Ca 2+（[Ca 2 +]cyt）升高的快速和短暂增加。使用转基因拟南芥表达的Ca 2+传感器水母发光蛋白，我们已经分离出EMS突变体受损的Ca 2+响应CWE在根或flg 22在芽。除了完成两个MAMP的突变体筛选外，延长期的目标是：（a）表征鉴定的突变体，证明它们的特异性并分析突变体中MAMP诱导的下游应答，（B）通过图位克隆鉴定选定数量的突变基因，（c）研究第二信使，例如磷脂的作用，作为两种系统中[Ca 2 +]的调节剂，和（d）从印度商陆CWE中纯化活性化合物。此外，cameleon系统将用于提高钙特征表征的分辨率。长期目标是将钙信号与下游反应联系起来，并填补目前植物-微生物相互作用期间钙信号传导知识的空白。

Calcium is a universal signal transduction second messenger. Like flg22 in leaves, a cell wall extract (CWE) from Piriformospora indica, which mimics the growth promotion effects of the fungus, induces a rapid and transient increase in cytoplasmic Ca2+ ([Ca2+]cyt) elevation in the roots. Using transgenic Arabidopsis expressing the Ca2+ sensor aequorin, we have isolated EMS mutants impaired in their Ca2+ response to the CWE in roots or to flg22 in shoots. In addition to completing the mutant screen for the two MAMPs, the aims during the extension period are: (a) to characterize the identified mutants, demonstrate their specificity and analyse MAMP-induced downstream responses in the mutants, (b) to identify a selected number of mutated genes by map-based cloning, (c) to investigate the role of second messengers, e.g. phospholipids, as modulators of [Ca2+] in both systems, and (d) to purify the active compound from the P. indica CWE. Additionally, the cameleon system will be used to improve the resolution of calcium signature characterization. The long term goal is to link the calcium signature to downstream responses and to fill in gaps in current knowledge of calcium signalling during plant-microbe interactions.