Plant Biology, Department of Biosciences, Viikki Biocenter, University of Helsinki, Finland.
Biochem J. 2012 Mar 15;442(3):573-81. doi: 10.1042/BJ20111739.
Transcriptional regulation of gene expression is one major determinant of developmental control and stress adaptation in virtually all living organisms. In recent years numerous transcription factors controlling various aspects of plant life have been identified. The activity of transcription factors needs to be regulated to prevent unspecific, prolonged or inappropriate responses. The transcription factor DREB2A (DEHYDRATION-RESPONSIVE ELEMENT BINDING 2A) has been identified as one of the main regulators of drought and heat responses, and it is regulated through protein stability. In the present paper we describe evidence that the interaction with RCD1 (RADICAL-INDUCED CELL DEATH 1) contributes to the control of DREB2A under a range of conditions. The interaction is mediated by a novel protein motif in DREB2A and a splice variant of DREB2A which lacks the interaction domain accumulates during heat stress and senescence. In addition RCD1 is rapidly degraded during heat stress, thus our results suggest that removal of RCD1 protein or the loss of the interaction domain in DREB2A appears to be required for proper DREB2A function under stress conditions.
基因表达的转录调控是几乎所有生物进行发育控制和应激适应的主要决定因素。近年来，已经鉴定出许多控制植物生命各个方面的转录因子。为了防止非特异性、延长或不适当的反应，转录因子的活性需要受到调控。DREB2A（脱水响应元件结合蛋白 2A）作为干旱和热响应的主要调节因子之一，其通过蛋白质稳定性进行调节。在本文中，我们描述了证据表明，与 RCD1（RADICAL-INDUCED CELL DEATH 1）的相互作用有助于在各种条件下控制 DREB2A。这种相互作用是由 DREB2A 中的一个新的蛋白质基序和一个缺乏相互作用域的 DREB2A 剪接变体介导的，该变体在热胁迫和衰老过程中积累。此外，RCD1 在热胁迫下迅速降解，因此我们的结果表明，在胁迫条件下，去除 RCD1 蛋白或 DREB2A 中的相互作用域似乎是 DREB2A 正常功能所必需的。
