Coactivator ASC‐2 mediates heat shock factor 1‐mediated transactivation dependent on heat shock

FEBS Letters

Kang, Ho Sung¹  Kim, Sun Hee¹  Hong, SunHwa¹  Heo, Mi Ae¹  Park, Min Jung¹  Cheong, JaeHun¹  Yoo, Mi Ae¹  Choi, Yoon Ha¹  Kim, Han Do¹ 

[1] Department of Molecular Biology, Pusan National University, Busan 609-735, South Korea

关键词: HSF-1;    ASC-2;    Heat shock;    Transactivation;    HSP;    heat shock protein;    HSF;    heat shock factor;    CBP;    cyclic adenosine monophosphate responsive element binding protein;    ERK;    extracellular regulated kinase;    ASC;    activating signal cointegrator;    SDS–PAGE;    sodium dodecyl sulfate–polyacrylamide gel electrophoresis;    GST;    glutathione S-transferase;   

DOI  :  10.1016/S0014-5793(04)00028-6

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Upon exposure to elevated temperatures, mammalian cells increase the expression of the heat shock proteins (HSP) through activation of the heat shock factor 1 (HSF1). Since most transcription factors require coactivators for efficient transcriptional activity, we tried to identify the coactivator(s) that interacts with and modulates the activities of HSF1. In vitro glutathione S-transferase (GST) pull-down assay revealed that HSF1 strongly interacts with activating signal cointegrator (ASC)-2 and weakly with cyclic adenosine monophosphate responsive element binding protein (CBP). We also show that cotransfection of ASC-2, but not CBP, potentiates HSF1-mediated transactivation based on its cognate element (heat shock element, HSE) linked to luciferase reporter. The molecular interaction of HSF1 and ASC-2 was stimulated by heat shock in cells and the overexpression of HSF1-interacting domain of ASC-2 inhibited the specific induced protein association and HSF1-mediated transactivation. Taking these results together, we suggest that ASC-2 in a novel coactivator for HSF1 and heat shock stress may contribute the strong active transcription complex through sequential recruitment of HSF1 and ASC-2.

【 授权许可】

Unknown