Integrin beta-4
Domain
The fibronectin type-III-like domains bind BPAG1 and plectin and probably also recruit BP230.
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 alpha-6/beta-4 is a receptor for laminin. It plays a critical structural role in the hemidesmosome of epithelial cells. Is required for the regulation of keratinocyte polarity and motility. ITGA6:ITGB4 binds to NRG1 (via EGF domain) and this binding is essential for NRG1-ERBB signaling. ITGA6:ITGB4 binds to IGF1 and this binding is essential for IGF1 signaling. ITGA6:ITGB4 binds to IGF2 and this binding is essential for IGF2 signaling.
Post-translational modifications
Palmitoylated by DHHC3 at several cysteines of the membrane-proximal region, enhancing stability and cell surface expression. Palmitoylation also promotes secondary association with tertaspanins (By similarity).
Sequence Similarities
Belongs to the integrin beta chain family.
Cellular localization
- Cell membrane
- Single-pass type I membrane protein
- Cell membrane
- Lipid-anchor
- Cell junction
- Hemidesmosome
- Colocalizes with DST at the leading edge of migrating keratinocytes.
Alternative names
CD104, Integrin beta-4, Itgb4