Hip (HSP70-interacting protein), also known as ST13 (suppression of tumorigenicity protein 13), is one of several co-chaperones that regulate activities of the HSP70 chaperone family. The expression of this gene is reported to be downregulated in colorectal carcinoma tissue suggesting that it is a candidate tumor suppressor gene. Hip functions to stabilize Hsc 70 in the ADP-bound state which has high affinity for substrate protein. Through its own chaperoning activity, Hip may contribute to the substrate specificity of the Hsc 70 complex.
