中介体亚基MED25调控植物激素信号转导的研究进展

doi:10.13560/j.cnki.biotech.bull.1985.2018-0487

摘要/Abstract

摘要： 由多亚基组成的中介体复合物（Mediator complex）是真核生物转录调控中不可或缺的纽带,它的核心功能就是将基因特异的转录因子和基于RNA聚合酶II的转录机器相连接,形成转录预起始复合物（Pre-initiation complex,PIC）,从而实现特定转录信号的传递。Mediator 25（MED25）是植物中介体复合物的一个多功能亚基,参与调控植物生长发育和抗逆境胁迫等多种复杂的生理过程。MED25可以和多种转录激活子（如MYCs、AP2/ERFs及ARFs等）、转录抑制子（如JAZs和Aux/IAAs等）以及其它中介体亚基（如MED13和MED16等）在蛋白水平上直接互作,调控植物激素茉莉酸（JA）、脱落酸（ABA）、生长素（Auxin）和乙烯（Ethylene）等信号途径以响应各种生物和非生物胁迫。近年来对MED25的靶标分离及功能鉴定已经成为一个热点话题。本文系统介绍了MED25在各激素信号途径转导中的调控作用机制,对深入讨论植物如何启动特定激素信号途径进而调控特定生理过程的分子机制提供新的研究思路。

关键词: 中介体复合物, MED25亚基, 茉莉酸, 脱落酸, 生长素, 乙烯

Abstract: The multi-subunit mediators regulate gene expression by bridging RNA polymerase II and kinds of transcription factors into Pre-Initiation Complex to trigger specific transcriptional program. Mediator25（MED25）is one subunit of the plant mediator complex,implicated in regulating plant development and stress tolerance. MED25 participated in response of biotic and abiotic stresses by interacting with transcription activators（e.g.,MYCs,AP2/ERFs and ARFs）,repressors（e.g.,JAZs and Aux/IAAs）and other mediator subunits（e.g.,MED13 and MED16）,and regulation of phytohormone（JA,ABA,ethylene and IAA）signaling pathways. The target separation and functional identification of MED25 have been a hot topic in recent years. In this paper,the essential roles of MED25 in various hormone signaling pathways were reviewed and provide novel insights into how the plants pass hormone-specific regulatory signals and transcriptionally control physiological processes.

Key words: mediator complex, MED25, jasmonic acid, abscisic acid, auxin, ethylene

窦悦, 刘美彤, 卢安娜, 吴佳洁, 王群青, 胥倩. 中介体亚基MED25调控植物激素信号转导的研究进展[J]. 生物技术通报, 2018, 34(7): 40-47.

DOU Yue, LIU Mei-tong, LU An-na, WU Jia-jie, WANG Qun-qing, XU Qian. Regulatory Mechanism of Mediator Subunit MED25 on Multi-phytohormone Signaling Pathways[J]. Biotechnology Bulletin, 2018, 34(7): 40-47.

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