J Exp Bot:中科院武汉植物园产祝龙研究组在干旱胁迫以及脱落酸信
JouRNAl of Experimental Botany杂志上发表中国科学院武汉植物园植物水分胁迫生物学产祝龙课题组发表的干旱胁迫以及脱落酸信号转导研究结果。王艳平研究员为论文第一作者，产祝龙研究员为论文通讯作者。
干旱胁迫是制约作物生长发育的主要环境因素之一，而植物激素脱落酸(ABA)在介导植物应答干旱胁迫、减少内源水分流失方面具有重要的调控作用。近些年在ABA信号转导方面已取得重要进展。有关ABA信号途径的调控仍有很多未知问题。
王艳平副研究员在研究员产祝龙的指导下，利用突变体筛选的方法鉴定得到一个ABA不敏感突变体，该基因编码一个与ABA受体PYL/PYR同源的Bet V 1蛋白MLP43。研究发现MLP43 作为一个正调控因子在介导拟南芥应答干旱和ABA信号转导方面具有重要的作用。MLP43 基因的缺失能够影响拟南芥叶片的水分流失速率、内源ROS水平、初生代谢物以及胁迫相关基因的表达。另外，MLP43能够与ABA信号转导重要成员SnRK2.6以及ABF1直接互作，并促进ABA下游报告基因的转录。
MLP43与SnRK2.6以及ABF1互作调控ABA信号通路
原文链接：
Major latex protein-like protein 43 (MLP43) functions as a positive regulator during abscisic acid responses and confers drought tolerance inArabidopsis thaliana
原文摘要：
Drought stress is one of the disadvantageous environmental conditions for plant growth and reproduction. Given the importance of abscisic acid (ABA) to plant growth and abiotic stress responses, identification of novel components involved in ABA signalling transduction is critical. In this study, we screened numerous Arabidopsis thaliana mutants by seed germination assay and identified a mutant mlp43 (major latex protein-like 43) with decreased ABA sensitivity in seed germination. The mlp43 mutant was sensitive to drought stress while the MLP43-overexpressed transgenic plants were drought tolerant. The tissue-specific expression pattern analysis showed that MLP43 was predominantly expressed in cotyledons, primary roots and apical meristems, and a subcellular localization study indicated that MLP43 was localized in the nucleus and cytoplasm. Physiological and biochemical analyses indicated that MLP43 functioned as a positive regulator in ABA- and drought-stress responses in Arabidopsisthrough regulating water loss efficiency, electrolyte leakage, ROS levels, and as well as ABA-responsive gene expression. Moreover, metabolite profiling analysis indicated that MLP43 could modulate the production of primary metabolites under drought stress conditions. Reconstitution of ABA signalling components in Arabidopsis protoplasts indicated thatMLP43 was involved in ABA signalling transduction and acted upstream of SnRK2s by directly interacting with SnRK2.6 and ABF1 in a yeast two-hybrid assay. Moreover, ABA and drought stress down-regulated MLP43expression as a negative feedback loop regulation to the performance ofMLP43 in ABA and drought stress responses. Therefore, this study provided new insights for interpretation of physiological and molecular mechanisms of Arabidopsis MLP43 mediating ABA signalling transduction and drought stress responses.
作者：产祝龙
