Anti-V1 antibodies enable researchers to detect and measure the V1 antigen in biological samples. This target is a reported synonym of the MTPN gene, which encodes myotrophin. This protein is known to function in the differentiation of certain cell types, among other biological roles. The human version of V1 has a canonical amino acid length of 118 residues and a protein mass of 12.9 kilodaltons. It is reported to be localized in the nucleus and cytoplasm of cells and widely expressed in many tissue types. V1 is a member of the Myotrophin protein family.