DNA-binding protein that specifically binds heat shock promoter elements (HSE) and activates transcription of non-classical heat-shock genes such as PDZD2 and PROM2. Protects cells against heat shock and proteotoxic stress. Cytoplasmic under normal conditions. Translocates to the nucleus in response to heat shock. Does not translocate to the nucleus in response to heat shock. Belongs to the HSF family.