passages.id: split_6_test_404_passage
passages.type: progene_text
passages.text: Under basal conditions , the human HSF1 protein is maintained as an inactive monomer through intramolecular interactions between two coiled - coil domains and interactions with heat shock proteins ; upon environmental , pharmacological , or physiological stress , HSF1 is converted to a homotrimer that binds to its cognate DNA binding site with high affinity .