Structural Investigation of HSP70-HSP90 and HSP90-TDF Interactions

Abstract

Tumor Differentiation Factor (TDF) is a pituitary protein, which is secreted into the blood stream and targets breast and prostate. The end effect of TDF on these tissues is differentiation of breast and prostate cells. However, it is not yet clear how TDF induces cell differentiation. Studies in our laboratory determined that the potential TDF receptor candidates are: HSPA8, a member of the 70 kDa heat shock protein family and HSP90 protein. Our previous studies also indicated that TDF may have an inducible receptor, composed of both HSP70 and HSP90, and that TDF signaling depends on the interaction of these proteins. Here we provide additional insights about the proposed interaction between HSP70 and HSP90 and about the HSP90-TDF interaction.