Itgb2
Domain
The VWFA domain (or beta I domain) contains three cation-binding sites: the ligand-associated metal ion-binding site (LIMBS or SyMBS), the metal ion-dependent adhesion site (MIDAS), and the adjacent MIDAS site (ADMIDAS). This domain is also part of the ligand-binding site.
Function
Integrin ITGAL/ITGB2 is a receptor for ICAM1, ICAM2, ICAM3 and ICAM4. Integrin ITGAL/ITGB2 is also a receptor for the secreted form of ubiquitin-like protein ISG15; the interaction is mediated by ITGAL (By similarity). Integrins ITGAM/ITGB2 and ITGAX/ITGB2 are receptors for the iC3b fragment of the third complement component and for fibrinogen. Integrin ITGAX/ITGB2 recognizes the sequence G-P-R in fibrinogen alpha-chain. Integrin ITGAM/ITGB2 recognizes P1 and P2 peptides of fibrinogen gamma chain. Integrin ITGAM/ITGB2 is also a receptor for factor X. Integrin ITGAD/ITGB2 is a receptor for ICAM3 and VCAM1. Contributes to natural killer cell cytotoxicity (By similarity). Involved in leukocyte adhesion and transmigration of leukocytes including T-cells and neutrophils (By similarity). Triggers neutrophil transmigration during lung injury through PTK2B/PYK2-mediated activation (PubMed:18587400). Integrin ITGAL/ITGB2 in association with ICAM3, contributes to apoptotic neutrophil phagocytosis by macrophages (By similarity). In association with alpha subunit ITGAM/CD11b, required for CD177-PRTN3-mediated activation of TNF primed neutrophils (By similarity). Integrin ITGAM/ITGB2 plays a critical role in mast cell development and in immune complex-mediated glomerulonephritis. Mice expressing a null mutation of the ITGAM subunit gene demonstrate increase in neutrophil accumulation, in response to a impaired degranulation and phagocytosis, events that apparently accelerate apoptosis in neutrophils. These mice develop obesity.
Post-translational modifications
Both Ser-747 and Ser-758 become phosphorylated when T-cells are exposed to phorbol esters. Phosphorylation on Thr-760 (but not on Ser-758) allows interaction with 14-3-3 proteins.
Sequence Similarities
Belongs to the integrin beta chain family.
Cellular localization
- Cell membrane
- Single-pass type I membrane protein
- Membrane raft
- Single-pass type I membrane protein
Alternative names
CD18, Integrin beta-2, Complement receptor C3 subunit beta, Itgb2