HSF1

Description

The HSF1 (heat shock transcription factor 1) is a protein-coding gene located on chromosome 8.

HSF1, also known as heat shock transcription factor 1, is a protein encoded by the HSF1 gene. It is highly conserved across eukaryotes and plays a vital role in the cell's response to various stressors, especially proteotoxic stress. HSF1 is composed of several domains:

DNA-Binding Domain (DBD): This domain recognizes specific DNA sequences called heat shock elements (HSEs) and facilitates the binding of HSF1 to DNA.
Oligomerization Domain (Leucine Zipper Domains): This domain enables HSF1 monomers to assemble into trimers, a crucial step in its activation.
Regulatory Domain (RD): This domain is involved in regulating the activity of HSF1.

HSF1 exists in a dynamic equilibrium between inactive monomeric and active trimeric forms. Under normal conditions, HSF1 remains in an inactive state, bound to a complex of chaperone proteins. Stressful conditions trigger the assembly of HSF1 into trimers, allowing it to bind to HSEs and activate the expression of heat shock proteins (HSPs). These proteins help protect cells from damage caused by stress.

HSF1 functions as a stress-inducible and DNA-binding transcription factor. It plays a central role in the transcriptional activation of the heat shock response (HSR), leading to the expression of heat shock proteins (HSPs) that protect cells from damage. In unstressed cells, HSF1 exists as an inactive monomer bound to a complex containing HSP90. Upon exposure to stress, HSF1 undergoes homotrimerization and translocates to the nucleus, where it binds to heat shock elements (HSEs) in the promoter regions of HSP genes. This activates transcription of HSPs, helping the cell cope with stress. Upon heat shock stress, HSF1 forms a chromatin-associated complex with TTC5/STRAP and p300/EP300 to further stimulate HSR transcription. Activation of HSF1 is reversible, and during recovery, it returns to its inactive form. HSF1 also has other functions independent of its transcriptional activity, including involvement in the regulation of mitotic progression, mRNA processing, and nuclear export of HSP70 mRNA.

HSF1 is also known as HSTF1.

Associated Diseases

WES Whole Exome Sequencing