O43765

SGTA (small glutamine-rich tetratricopeptide repeat (TPR)-containing protein A or alpha), also known as SGT, hSGT or UBP (Vpu-binding protein), is a ubiquitously expressed protein that contains three TPR protein-protein interaction repeats. SGTA is believed to function as a component of the androgen receptor (AR)-chaperone-co-chaperone complex, acting as a co-chaperone involved in androgen signaling. More specifically, SGTA binds to the hinge region of the AR functions to retain the AR in the cytoplasm, thereby inhibiting androgen signaling. In addition, SGTA functions as a co-chaperone for HSP 90 and HSP 70, two proteins known to participate in apoptosis. On the basis of its role in apoptosis and androgen signaling, SGTA is a potential candidate for PCOS (polycystic ovary syndrome), a disorder characterized by androgen excess, obesity and menstrual disturbances. SGTA also interacts with the nonstructural Parvovirus protein NS1 and the HIV-1 proteins Vpu and Gag.