Division of Health Sciences, Kanazawa University Graduate School of Medical Science, Ishikawa, Japan.
FEBS J. 2018 Sep;285(17):3215-3224. doi: 10.1111/febs.14604. Epub 2018 Aug 18.
TATA-binding protein-associated factor 7 (TAF7), a dissociable component of the general transcription factor IID (TFIID), plays a role as a check-point regulator at the step of RNA polymerase II (Pol II) transcription initiation. Here, we focused on the role of TAF7 in heat-shocked cells, where its expression is induced by heat shock factor HSF1. TAF7 is a phosphoprotein, and the phosphorylation status is related to its interaction with TFIID and to its stability controlled by the ubiquitin-proteasome pathway. TAF7 is necessary for the prolonged expression of heat shock protein genes and for efficient recovery of heat-shocked cells. During sustained transcription, TAF7, presumably its TFIID-independent form, binds the promoter and enhances the levels of Pol II at the gene body but not the promoter. These results showed the novel function of TAF7 that is necessary for the transition from initiation to elongation in multiple-round transcription.
TATA 结合蛋白相关因子 7（TAF7）是一般转录因子IID（TFIID）的可分离成分，在 RNA 聚合酶 II（Pol II）转录起始步骤中发挥检查点调节因子的作用。在这里，我们专注于 TAF7 在热休克细胞中的作用，其中其表达由热休克因子 HSF1 诱导。TAF7 是一种磷酸化蛋白，其磷酸化状态与其与 TFIID 的相互作用以及其稳定性有关，后者由泛素-蛋白酶体途径控制。TAF7 是热休克蛋白基因的延长表达和热休克细胞的有效恢复所必需的。在持续转录过程中，TAF7（推测为其与 TFIID 无关的形式）结合启动子并增强基因体中 Pol II 的水平，但不增强启动子处的水平。这些结果显示了 TAF7 的新功能，该功能对于多轮转录从起始到延伸的转变是必需的。
