Sialomucin that may play a key role in hematopoiesis. May be involved in cell adhesion. Promotes myogenesis by enhancing CXCR4-dependent cell motility. Positively regulates myoblast migration and promotes myoblast fusion into myotubes (By similarity). Interacts with CXCR4. Ubiquitous. Expressed at highest levels in the liver, kidney, lung and intestine. Highly N- and O-glycosylated; contains sialic acid. Belongs to the CD164 family.