Anti-TMEM191B antibodies are used in the immunodetection of the protein transmembrane protein 191B. In humans, the canonical protein has a reported length of 346 amino acid residues and a mass of 39.1 kDa. Its subcellular localization is in the membrane. It is a member of the TMEM191 protein family. TMEM191B gene orthologs have been reported in the mouse and chimpanzee species.