Histidine (His83) is Essential for Heat Shock Factor 1 (HSF1) Activation in Protecting against Acid pH Stress

• Published in: Bulletin of the Korean Chemical Society Vol. 34; no. 11; pp. 3405 - 3409
• Main Authors: Lu, Ming, Chang, Ziwei, Park, Jang-Su
• Format: Journal Article
• Language: English
• Published: 대한화학회 20.11.2013
• Subjects: 화학
• ISSN: 0253-2964; 1229-5949
• DOI: 10.5012/bkcs.2013.34.11.3405

The activation of heat shock factor 1 (HSF1) can be induced by the changes in environmental pH, but the mechanism of HSF1 activation by acidification is not completely understood. This paper reports that a low pH (pH~6.0) can trigger human HSF1 activation. Considering the involvement of the imidazole group of histidine residues under acid pH stress, an in vitro EMSA experiment, Trp-fluorescence spectroscopy, and protein structural analysis showed that the residue, His83, is the essential for pH-dependent human HSF1-activation. To determine the roles of His83 in the HSF1-mediated stress response affecting the cellular acid resistance, mouse embryo fibroblasts with normal wild-type or mutant mouse HSF1 expression were preconditioned by heating or pH stress. The results suggest that His83 is essential for HSF1 activation or the HSF1-mediated transcription of heat shock proteins, in protecting cells from acid pH stress. KCI Citation Count: 1