Heat shock protein 90 (HSP90) is a molecular chaperone and one of the most abundant proteins in unstressed cells. In mammalian cells, there are two genes encoding cytosolic Hsp90 homologues, with the human Hsp90α showing 85% sequence identity to Hsp90β. The recombinant Hsp90 produced from Sf9 cells represents the full length (a.a. 1-723) of Hsp90β subunit.

Heat shock protein 90kDa beta member 1 (HSP90B1) is activated during apoptosis. It is associated with the endoplasmic reticulum membrane and undergoes specific proteolytic cleavage leading to the activation of the caspase CPP32 and initiation of DNA fragmentation. The protein protects cells against flux in Ca²⁺ homeostasis, which would otherwise result in cell death. It maintains the chromosomal stability in mammalian cells by associating with FAC. HSP90B1 chaperones toll-like receptors (TLRs) and thus optimizes the B cell functioning. These proteins are also the main downstream chaperones which mediate the ER unfolded protein response (UPR), which is very essential for maintaining protein homeostasis in the ER.

Protein is provided in a solution of 40 mM HEPES/KOH, pH 7.5, containing 400 mM potassium chloride and 5% glycerol.

Centrifuge the vial prior to opening. Avoid freeze-thaw cycles