水稻逆境相关转录因子研究进展

Research advance of the transcription factors related to stress resistances in rice

关键词:  水稻  逆境胁迫  抗逆性  转录因子  基因表达

Key words:  rice  adversity stress  stress resistance  transcriptional factor  gene expression

摘要:

干旱、盐碱、高温和低温等逆境因子胁迫水稻的生长发育,进而影响水稻的产量和品质。因此,研究水稻的抗逆性,尤其是揭示其抗逆分子机理具有重要的生物学意义。近年来,水稻抗逆分子机理的研究主要集中在转录因子及其分子调控机制方面。在水稻中,目前研究较多的转录因子类型主要有bZIP、MYB/MYC、WRKY、AP2/EREBP和NAC,它们的结构通常由DNA结合结构域、转录活化结构域、寡聚化位点和核定位信号组成。转录因子在水稻逆境信号转导途径中起着中心调节作用,它们将逆境信号传递和放大,通过与目的基因启动子区中顺式作用元件特异结合,调控下游多个逆境相关基因的表达,从而引起水稻对逆境应答反应,最终实现水稻获得综合抗逆性的提升。该文简要概述了植物转录因子的调控机制、结构特点、分类与功能特性,重点论述了转录因子在水稻抗逆中的作用,指出了转录因子应用过程中转基因水稻产生的负效应问题,并提出了解决负效应问题的研究思路,同时展望了今后转录因子的研究前景,以期为挖掘和应用新的水稻转录因子基因以及阐明其抗逆调控机制提供理论依据。

Abstract:

Adverse environmental factors,such as drought,salinization,high temperature and low temperature,severely threaten rice growth and development, and then damage rice yield and quality. Therefore,the research on rice resistance, especially dissecting molecular mechanism of rice, has important biological significance. In recent years,the reports on molecular mechanism of rice resistance have been mainly focused on isolating and identifying transcriptional factor genes as well as their regulatory mechanisms. For example, several main types of transcriptional factors, such as bZIP,MYB/ MYC,WRKY,AP2/EREBP and NAC families,were relatively clearly studied in rice. Each of these transcriptional factors was usually composed of a DNA-binding domain,a transcription regulation domain,a oligomerization site and a nuclear localization domain. Transcriptional factors played a pivotal role in the adversity signal transduction pathways of rice,they acted as the integrators of environmental factors to transmit and amplify adversity signal,and then regulated many of stress-related genes expression by specifically interacting with cis-acting elements existed in the promoter sequences of target genes, which made rice response to adversity stresses,eventually confers enhanced comprehensive stress resistances in rice. In this review, the regulatory mechanisms,structural characteristics,classification and functional properties of transcriptional factors are summarized,their regulatory roles in the stress response and tolerance of rice were discussed,the negative effects of genetically modified rice in the process of transcriptional factors application were mentioned,and research approaches of solving the negative effects problem were suggested,as well as the future study of transcriptional factors were discussed. Overall,the aim of this paper was to provide the basis for identifying and applying new transcriptional factor genes from rice,and clarifying their molecular mechanism in rice stress resistances.