Trimerized HSF1 binds to heat-shock element of DNA and activate HSFs transcription.

Formation of oligomer is a critical step in the activation of HSF proteins.

The oligomerization is mediated by the HR-A/B coiled-coil region.

The HR-A/B coiled-coil domains of Skn7 and HSF1 are  remarkably  similar.

Here shows the structure of trimerized Skn7.

The coiled-coils are linked by disulfide bridge involving Cys185 in each chain.

Title: Structure of human heat-shock transcription factor 1 in complex with DNA.
Authors: Neudegger, T., Verghese, J., Hayer-Hartl, M., Hartl, F.U., Bracher, A.
Journal: Nat Struct Mol Biol. 2016 Feb;23(2):140-6. (PubMed)

PDB ID: 5D5Z

PDB ID: 5D5Y