CD72
Function
Co-receptor of B cell receptor (BCR) that plays both positive and negative roles on B-cell functions. Recognizes the Sm/ribonucleoprotein (RNP) self-antigen ligand, and coligation of CD72 and BCR inhibits BCR signaling. Mechanistically, ligand binding leads to the recruitment of PTPN6/SHP-1 to the BCR complex which is inhibitory to BCR signaling. Acts also as a ligand for CD5 and thereby plays a critical role in maintaining regulatory T and B-cell homeostasis.
Post-translational modifications
Phosphorylated upon engagement of the B-cell receptor, probably by LYN or SYK. Phosphorylation at Tyr-7 is important for interaction with PTPN6/SHP-1.
Tissue Specificity
Pre-B-cells and B-cells but not terminally differentiated plasma cells.
Cellular localization
- Membrane
- Single-pass type II membrane protein
Alternative names
CD72, B-cell differentiation antigen CD72, Lyb-2