A member of the prominin family, AC133 Antigen is a 5-transmembrane antigen occurring as several isoforms produced by alternative splicing which are processed into mature forms. In humans, it is expressed as a subset of CD34 (bright) human hematopoietic stem cells and CD34 positive leukemias. Functionally, it is associated with roles in cell differentiation, proliferation, and apoptosis. Specifically, it regulates the organization of apical plasma membrane in epithelial cells, disk morphogenesis during early retinal development, MAPK and Akt signaling pathways, and in cholesterol metabolism.

Synonyms: Prominin-Like PROML1, PROML1, AC141 Antigen, Prominin-1, AC133 Antigen, AC133-1 Antigen, 0, Fudenine, AC133-2 Antigen, Prominin, CD133 Antigen, AC133 2 Antigen, Prominin 1, AC133 1 Antigen, Antigen, AC133, Antigen, AC133-1, Antigen, AC141, Antigen, CD133, Prominin Like PROML1, Antigen, AC133-2