Background
The SGT/UBP protein (also known as small glutamine-rich tetratricopeptide repeat (TPR)-
containing protein A, Alpha-SGT, Vpu-Binding Protein, UBP, SGTA, SGT or SGT1) is a ubiquitously expressed cochaperone
protein which contains three TPR protein-protein interaction repeats. SGT/UBP binds to Hsp70, negatively
affecting its function. SGT/UBP interacts with the Viral protein U (Vpu) and Group specific Antigen (Gag) proteins from
HIV-1 and with the nonstructural protein NS-1 of parvovirus H-1; the protein/chaperone complex is thought to be involved
in Vpu function and HIV particle exit and in parvovirus DNA replication. SGT/UBP also interacts with SARS-CoV
Accessory Protein 7a, although the function remains unknown. Furthermore, SGT/UBP is believed to be a component of
the androgen receptor (AR)-chaperone-co-chaperone complex, acting as a co-chaperone involved in androgen signaling.