Anti-vpu antibodies enable researchers to detect and measure the vpu antigen in biological samples. This target is a reported synonym of the SGTA gene, which encodes small glutamine rich tetratricopeptide repeat co-chaperone alpha. This protein is a reported co-chaperone that binds misfolded and hydrophobic patches-containing client proteins in the cytosol. The human version of vpu has a canonical amino acid length of 313 residues and a protein mass of 34.1 kilodaltons. It is reported to be localized in the nucleus and cytoplasm of cells and widely expressed in many tissue types. vpu is a member of the SGT protein family.