Overview:

HSP90β is a member of the HSP90 family of proteins which are important molecular chaperones involved in signal transduction, cell cycle control, stress management, and folding, degradation, and transport of proteins (1). HSP90 proteins have been found in a variety of organisms suggesting that they are ancient and conserved. HSP90 binds to client proteins (such as steroid receptors, AKT, Bcr-Abl, Apaf-1, survivin, cyclin dependent kinases) and acts as a molecular chaperone. Failure of HSP90 chaperone activity leads to misfolding of client proteins, which leads to ubiquitination and proteasome degradation, and thus deregulation of cellular homeostasis (2).

References:

1. Csermely, P. et al: The 90-kDa molecular chaperone family: structure, function, and clinical applications. Pharmacol Ther. 1998 Aug;79(2):129-68.

2. Georgakis, G.V. et al: Heat-shock protein 90 inhibitors in cancer therapy: 17AAG and beyond. Future Oncol. 2005 Apr;1(2):273-81.