Interaction between heat shock transcription factor and transcription initiation complex.

热休克转录因子和转录起始复合物之间的相互作用。

• 批准号: 13680760
• 负责人: SAKURAI Hiroshi
• 金额: $ 2.24万
• 依托单位: Kanazawa University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13680760/
• 关键词: stress response; heat shock factor; phosphorylation; yeast; 基本転写因子; 転写開始; 抑圧変異; 酵母

The transcription activation signals of transcription activators are transmitted to the transcription initiation complex via intermediary factors such as Mediator and TAF(TBP-associated factor). The initiation complex consists of RNA polymerase II and the general transcription factors TBP,TFIIB,TFIIE,TFIIF,and TFIIH. By using the methods of yeast molecular genetics, it has been disclosed that activity of the TFIIH kinase(encoded by the KIN28 gene), which phosphorylates the carboxy-terminal domain(CTD) of RNA polymerase II, is dispensable for activation of several stress responsive genes such as heat shock genes. In this study, I have shown that the Kin28-independent activation of the heat-inducible genes is mediated by the heat shock transaction factor Hsfl. In addition, the general transcription factor IIE, which regulates the kinase activity of Kin28, was dispensable for copper-induced transcription of the CUP1 gene encoding copper metallothionein. Transcription of CUP1 is regulated by Hsfl and Aoe 1(copper-inducible activator). I further analyzed the Kin28-and TFIIE-independent transcription mechanisms and revealed the following. 1)The TFIIE-independent activation of CUP1 is mediated by oertain components of the Mediator complex. 2)The recruitment of TAFs, another well-known intermediary factor, is involved in the Kin28-independent transcription by Hsfl. 3) The C-terminal half of Hsfl has activities to recruit TAFs to a promoter and to undergo transcription independently of Kin28. 4)The C-terminal region of Hsfl contains a novel domain that regulates heat-inducible phosphorylation of Hsfl. These results illustrated that an alternate pathway of transcription reaction, in which a specific domain of activator plays a critical role in abrogation of requirement for subset of general transcription factors that are prerequisites in the main pathway of the transcription reaction.

转录激活因子的转录激活信号通过Mediator、TAF(TBP相关因子)等中介因子传递至转录起始复合物。起始复合物由RNA聚合酶II和通用转录因子TBP、TFIIB、TFIIE、TFIIF和TFIIH组成。利用酵母分子遗传学方法，揭示了磷酸化RNA聚合酶II羧基末端结构域(CTD)的TFIIH激酶(由KIN28基因编码)的活性对于热休克基因等多种应激反应基因的激活是必不可少的。在这项研究中，我证明了热诱导基因的独立于 Kin28 的激活是由热休克交易因子 Hsfl 介导的。此外，调节Kin28激酶活性的通用转录因子IIE对于铜诱导的编码铜金属硫蛋白的CUP1基因的转录来说是可有可无的。 CUP1 的转录受 Hsfl 和 Aoe 1（铜诱导激活剂）的调节。我进一步分析了 Kin28 和 TFIIE 独立的转录机制，并揭示了以下内容。 1) CUP1 的 TFIIE 独立激活是由介体复合物的某些成分介导的。 2)TAFs的募集是另一个众所周知的中间因子，参与Hsfl的Kin28独立转录。 3) Hsfl的C末端一半具有将TAF招募至启动子并独立于Kin28进行转录的活性。 4)Hsfl的C端区域含有一个调节Hsfl热诱导磷酸化的新结构域。这些结果说明了转录反应的替代途径，其中激活剂的特定结构域在消除对一般转录因子子集的需求方面发挥着关键作用，而一般转录因子子集是转录反应主要途径的先决条件。

项目成果

Sakurai, H., Fukasawa, T.: "A novel domain of the yeast heat shock transcription factor that regulates its activation function."Biochemical and Biophysical Research Communications. 285・3. 696-701 (2001)

Sakurai, H., Fukasawa, T.：“调节其激活功能的酵母热休克转录因子的新结构域。”生物化学和生物物理研究通讯 285・3（2001）。

N.Hashikawa, H.Sakurai: "Phosphorylation of yeast heat shock transcription factor is implicated in gene-specific activation that depends on the architecture of heat shock element"Molecular and Cellular Biology. 印刷中. (2004)

N.Hashikawa、H.Sakurai：“酵母热休克转录因子的磷酸化与取决于热休克元件结构的基因特异性激活有关”《分子与细胞生物学》出版（2004 年）。

Sakurai, H., Fukasawa, T.: "Artificial recruitment of certain Mediator components affects requirement of basal transcription factor IIE."Genes to Cells. 8・1. 41-51 (2003)

Sakurai, H., Fukasawa, T.：“某些介体成分的人工募集会影响基础转录因子 IIE 的需求。”Genes to Cells 8・1 (2003)。

H.Sakurai et al.: "Carboxy-terminal region of the yeast heat shock transcription factor contains two domains that make transcription independent of the TFIIH protein kinase"Genes to Cells. 8・12. 951-961 (2003)

H.Sakurai 等人：“酵母热休克转录因子的羧基末端区域包含两个使转录独立于 TFIIH 蛋白激酶的结构域”，Genes to Cells 8·12 (2003)。

Sakurai, H., Fukasawa, T.: "Artificial recruitment of certain Mediator components affects requirement of basal transcription factor IIE."Genes to Cells. 8. 41-51 (2003)

Sakurai, H., Fukasawa, T.：“某些介体成分的人工募集会影响基础转录因子 IIE 的需求。”基因到细胞。