Miller Gad, Mittler Ron
Department of Biochemistry and Molecular Biology, University of Nevada, Mail Stop 200, Reno, NV 89557, USA.
Ann Bot. 2006 Aug;98(2):279-88. doi: 10.1093/aob/mcl107. Epub 2006 Jun 1.
Heat shock transcription factors (Hsfs) are modular transcription factors encoded by a large gene family in plants. They bind to the consensus sequence 'nGAAnnTCCn' found in the promoters of many defence genes, and are thought to function as a highly redundant and flexible gene network that controls the response of plants to different environmental stress conditions, including biotic and abiotic stresses. Hsf proteins encoded by different genes exhibit a high degree of complexity in their interactions. They can potentially bind and activate their own promoters, as well as the promoters of other members of their gene family, and they can form homo- or heterotrimers resulting in altered nuclear localization, as well as enhanced or suppressed transcription.
In this review, we summarize recent studies on Hsf function in Arabidopsis and tomato and present evidence obtained from microarray expression studies in Arabidopsis that the Hsf gene network is highly flexible and specialized, with specific members and/or member combinations controlling the response of plants to particular stress conditions. In addition, we describe recent studies that support the hypothesis that certain Hsfs function as molecular sensors that directly sense reactive oxygen species (ROS) and control the expression of oxidative stress response genes during oxidative stress.
热激转录因子（Hsfs）是植物中一个大基因家族编码的模块化转录因子。它们与许多防御基因启动子中发现的共有序列“nGAAnnTCCn”结合，被认为作为一个高度冗余且灵活的基因网络发挥作用，该网络控制植物对不同环境胁迫条件的响应，包括生物和非生物胁迫。不同基因编码的Hsf蛋白在其相互作用中表现出高度复杂性。它们可能结合并激活自身的启动子以及其基因家族其他成员的启动子，并且它们可以形成同三聚体或异三聚体，导致核定位改变以及转录增强或抑制。
在本综述中，我们总结了拟南芥和番茄中关于Hsf功能的最新研究，并展示了从拟南芥微阵列表达研究中获得的证据，即Hsf基因网络高度灵活且具有特异性，特定成员和/或成员组合控制植物对特定胁迫条件的响应。此外，我们描述了最近的研究，这些研究支持了某些Hsf作为分子传感器直接感知活性氧（ROS）并在氧化胁迫期间控制氧化应激反应基因表达的假说。
