质膜CYBDOM蛋白促进活性氧产生、侧根发育和抗旱性的机理

项目名称： 质膜CYBDOM蛋白促进活性氧产生、侧根发育和抗旱性的机理

项目编号： No.31470361

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 生物科学

项目作者： 邓馨

作者单位： 中国科学院植物研究所

项目金额： 90万元

中文摘要： CYBDOM蛋白是真核生物中一类含细胞色素b561结构域（CYB561）和多巴胺β-羟化酶结构域（DOMON）的功能未知的膜蛋白。我们从耐脱水的复苏植物旋蒴苣苔中克隆到一个CYBDOM基因，该基因受干旱和活性氧诱导表达，在侧根形成部位大量表达；过表达使转基因植物生长受抑，但ROS含量和侧根数目增加，抗旱性提高。ROS积累在转基因植物的侧根原基部位尤为显著。预试验结果表明该蛋白以类似PIN1内吞的方式进行胞内循环，同时抑制PIN1蛋白的胞内循环。本项目拟在此基础上，利用分子、生化、细胞和遗传学手段对CYBDOM蛋白介导ROS产生、侧根增加、抗旱性提高的功能和作用机理进行深入研究，揭示其调控逆境诱导形态反应的分子基础；并通过与模式植物同源基因的比较研究，阐明CYBDOM蛋白所介导的ROS和生长素的交互调节在植物耐旱性中的作用，为复苏植物耐旱适应的整合生物学机制提供一个新视角。

中文关键词： CYBDOM蛋白；侧根发育；抗旱机制；复苏植物；活性氧

英文摘要： CYBDOM is a multigenic protein family ubiquitously existed in eukaryotes, whereas the physiological functions of this type of proteins have not been clearly characterized. It is composed of a C terminal CYB561 and an N terminal DOMON domain. Previously, we have identified a dehydration-induced gene from the resurrection plant Boea hygrometrica, which encoded a plasma membrane-localized CYBDOM protein and was designated BhCYBDOM1. Constitutively expression of this gene in Arabidopsis caused significant ROS accumulation and showed a series of ROS-related phenotypes, including growth retardation, late-bolting, more lateral roots and drought tolerance. Preliminary results indicated that BhCYBDOM1 expressed in the lateral root primordium (LRP), which was in agreement with the observation that ROS accumulated in LRP in the plants overexpressing BhCYBDOM1.BhCYBDOM1 recycled between plasma membrane and endocytotic vesicles in the same manner as PIN1, the major auxin efflux carrier.On the other hand,PIN1 cycling was blocked by BhCYBDOM1.Based on these data, the proposed study aims to further elucidate the roles of CYBDOM proteins in regulating ROS production, LRP formation, and drought tolerance by combinations of molecular, biochemical, cellular and genetic approaches, and by comparative analysis of BhCYBDOM1 with its homologues from Arabidopsis. This project will provide the first experimental evidence for the function of CYBDOM proteins and a new viewpoint for the integrative regulation mechanisms of dehydration tolerance in B. hygrometrica, and eventually be benefit to deepen our understanding of the interaction of ROS, auxin in drought-stressed plants.

英文关键词： CYBDOM protein;Lateral root development;Mechanisms of drought tolerance;Resurrection plant;ROS