State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng 475001, China.
Int J Mol Sci. 2020 Oct 20;21(20):7755. doi: 10.3390/ijms21207755.
As an evolutionarily conserved multi-protein complex, the Mediator complex modulates the association between transcription factors and RNA polymerase II to precisely regulate gene transcription. Although numerous studies have shown the diverse functions of Mediator complex in plant development, flowering, hormone signaling, and biotic stress response, its roles in the Abscisic acid (ABA) signaling pathway and abiotic stress response remain largely unclear. It has been recognized that the phytohormone, ABA, plays a predominant role in regulating plant adaption to various abiotic stresses as ABA can trigger extensive changes in the transcriptome to help the plants respond to environmental stimuli. Over the past decade, the Mediator complex has been revealed to play key roles in not only regulating the ABA signaling transduction but also in the abiotic stress responses. In this review, we will summarize current knowledge of the Mediator complex in regulating the plants' response to ABA as well as to the abiotic stresses of cold, drought and high salinity. We will particularly emphasize the involvement of multi-functional subunits of MED25, MED18, MED16, and CDK8 in response to ABA and environmental perturbation. Additionally, we will discuss potential research directions available for further deciphering the role of Mediator complex in regulating ABA and other abiotic stress responses.
作为一个进化上保守的多蛋白复合物，中介复合物调节转录因子和 RNA 聚合酶 II 之间的关联，以精确调节基因转录。尽管许多研究表明中介复合物在植物发育、开花、激素信号和生物胁迫反应中具有多种功能，但它在脱落酸（ABA）信号通路和非生物胁迫反应中的作用在很大程度上仍不清楚。已认识到，植物激素 ABA 在调节植物对各种非生物胁迫的适应中起着主要作用，因为 ABA 可以引发转录组的广泛变化，帮助植物对环境刺激做出反应。在过去的十年中，中介复合物不仅被揭示在调节 ABA 信号转导中起着关键作用，而且在非生物胁迫反应中也起着关键作用。在这篇综述中，我们将总结中介复合物在调节植物对 ABA 以及对冷、干旱和高盐等非生物胁迫的反应方面的最新知识。我们将特别强调多功能亚基 MED25、MED18、MED16 和 CDK8 在响应 ABA 和环境胁迫中的参与。此外，我们将讨论进一步解析中介复合物在调节 ABA 和其他非生物胁迫反应中的作用的潜在研究方向。
