Anti-MASTR antibodies enable researchers to detect and measure the MASTR antigen in biological samples. This target is a reported synonym of the MAMSTR gene, which encodes MEF2 activating motif and SAP domain containing transcriptional regulator. This protein is known to function in myotube differentiation and the regulation of transcription, among other biological roles. The human version of MASTR has a canonical amino acid length of 415 residues and a protein mass of 44.6 kilodaltons, although 3 isoforms have been identified. It is reported to be localized in the nucleus of cells.