ITGB

ITGB refers to the family of integrin beta subunits, which are transmembrane proteins that pair with alpha subunits to form integrin receptors. In humans and other vertebrates, beta subunits are encoded by ITGB genes and determine many aspects of receptor signaling and ligand specificity. The beta subunits associate with various alpha subunits to create heterodimers that mediate cell–extracellular matrix and cell–cell adhesion, and they participate in signal transduction that influences cell migration, proliferation, survival, and tissue organization.

Key members and partnerships

- ITGB1 forms multiple receptors with different alpha chains, such as α1β1, α2β1, α4β1, and α5β1, and contributes to adhesion to collagens and fibronectin.

- ITGB2 encodes the beta-2 integrin chain, which pairs with CD11 family alpha subunits (for example, ITGAL to form LFA-1, and ITGAM to form Mac-1) and is essential for leukocyte adhesion and migration.

- ITGB3 pairs with ITGAV to form αVβ3 and with ITGA2B to form αIIbβ3, the latter of which is a key platelet receptor for fibrinogen.

- ITGB4 forms α6β4, a distinctive receptor in epithelial cells that participates in hemidesmosomes and basal membrane adhesion.

- ITGB5, ITGB6, ITGB7, and ITGB8 pair with various alpha subunits (notably ITGAV for αV-containing complexes or ITGA4/ITGAE for β7) to form receptors such as αVβ5, αVβ6, α4β7, αEβ7, and αVβ8, with roles in adhesion and signaling in diverse tissues.

Clinical and biological relevance

Dysregulation or mutations of ITGB genes can affect immune cell trafficking, tissue integrity, and wound healing. Certain conditions, such as leukocyte adhesion deficiencies linked to ITGB2, highlight the essential role of beta subunits in physiology. Integrin beta subunits are also studied as targets in cancer, inflammatory diseases, and platelet function disorders.