CLF抑制及SHB1激活PIF3和PIF4表达的研究

项目名称： CLF抑制及SHB1激活PIF3和PIF4表达的研究

项目编号： No.31470379

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 植物学

项目作者： 倪敏

作者单位： 山东农业大学

项目金额： 88万元

中文摘要： 光调节植物幼苗去黄化、光合能力发育及光周期诱导开花。光信号的接收及传导通过改变基因表达影响植物的形态与产量。高等植物通过吸收红光和远红光的光敏色素及吸收蓝光和紫外-A的隐花色素响应光环境。我们前期在一个上胚轴延长功能获得性突变体shb1-D中克隆到SHB1。SHB1定位于细胞核中，其在光信号传导中的作用仍不清楚。我们发现两个光信号传导关键基因PIF3和PIF4在黑暗中表达甚低。此暗抑制与PRC2组成亚基CLF有关，SHB1与CLF互作可能抑制其活性。我们又发现SHB1作用于PIF3和PIF4启动子，在红光下上调PIF3及PIF4表达。本课题将探索光诱导基因在黑暗中被PRC2抑制及此抑制可被SHB1在红光下部分去活，进而研究SHB1被招募到PIF3和PIF4启动子激活其表达。上述研究将对我们理解光信号传导及植物与环境互作提供重要信息。

中文关键词： CLF；组蛋白修饰；PIF表达；SHB1调节；光信号

英文摘要： Light regulates early seedling de-etiolation, photosynthetic capacity development, and photoperiodic flowering. Light perception and signaling alter gene expression, initiate morphogenic responses, and contributes significantly to crop yield. Higher plants monitor their ambient light signals through the red/far-red absorbing phytochromes and the blue/UV-A light absorbing cryptochromes. We previously identified SHB1 from a long hypocotyl gain-of-function mutant shb1-D. SHB1 localizes to the nucleus. How SHB1 functions in light signaling remains elusive. The expression of two key light signaling genes, PIF3 and PIF4, is minimal in the dark. The dark repression possibly involves CLF, a component of PRC2. SHB1 interacts with CLF and may inhibit CLF activity. SHB1 up-regulates the expression of PIF3 and PIF4 under red light, and associates with PIF3 and PIF4 promoters in vivo. In this proposal, we will explore if the light-inducible genes are repressed in general by polycomb proteins in the dark, and this repression is partly inactivated by SHB1 under red light. We will also investigate how SHB1 is recruited to PIF3 and PIF4 promoters and activate their transcription. The proposed research will add new piece of information to our current understanding of light signaling and plant interaction with environment.

英文关键词： CLF;histone modification;PIF expression;SHB1 regulation;light signaling