Heat shock factor binding protein 1 (HSBP1)

Heat shock factor binding protein 1 (HSBP1) is a small, highly conserved coiled-coil protein comprised of 76 amino acids that functions as a negative regulator of the cellular heat shock response. HSBP1 binds specifically to the trimeric, active form of heat shock factor 1 (HSF1)—a master transcription factor of the heat shock protein family—in the nucleus and represses HSF1's DNA-binding and transactivation activity, effectively downregulating the expression of heat shock proteins required for cellular protection and protein folding under stress. Structural studies show HSBP1 predominantly forms trimers, with a unique alpha-helical organization enabling its regulatory function[1][4][5]. Expression of HSBP1 is linked to tumor differentiation in nasopharyngeal carcinoma, with lower levels in poorly differentiated, therapy-resistant subtypes[2]. There is no evidence for clinically approved drugs targeting HSBP1, but its regulatory effect on stress responses may have implications in cancer biology, aging, and cell survival.

Other names

Heat shock factor-binding protein 1HSBP1HSF1BPNPC-A-13Nasopharyngeal carcinoma-associated antigen 13

Not applicable (no direct drugs), but mechanistically, HSBP1 negatively regulates HSF1 activity, reducing heat shock protein expression[4][5].