Abstract
The activation of heat shock transcription factor-1 (HSF-1) after treatment of mammalian cells with stresses such as heat shock, heavy metals, or ethanol induces the synthesis of heat shock proteins. HSF-1 is phosphorylated at normal growth temperature and is hyperphosphorylated upon stress. We recently presented evidence that HSF-1 can be phosphorylated by the mitogen activated protein kinase, ERK1, and that such phosphorylation appears to negatively regulate the activity of HSF-1. In this report, we have tested the ability of ERK1 to phosphorylate various HSF-1 deletion mutants. Our results show that ERK1 phosphorylation is dependent on a region of HSF-1 extending from amino acids 280 to 308. This region contains three serine residues that are potential ERK1 phosphorylation sites. The region falls within a previously defined regulatory domain of HSF-1. The possibility of protein kinases other than ERK1 phosphorylating HSF-1 was also examined using in-gel kinase assays. The results show that HSF-1 can be phosphorylated in a ras-dependent manner by other members of the MAP kinase family such as JNK and p38 protein kinases and possibly others.
Original language | English (US) |
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Pages (from-to) | 43-54 |
Number of pages | 12 |
Journal | Journal of cellular biochemistry |
Volume | 67 |
Issue number | 1 |
DOIs | |
State | Published - Oct 1 1997 |
Keywords
- ERK1
- HSF-1
- Heat shock
- MAP kinases
- Phosphorylation
ASJC Scopus subject areas
- Biochemistry
- Molecular Biology
- Cell Biology