ITGB1

Integrins are heterodimeric proteins made up of alpha and beta subunits. At least 18 alpha and 8 beta subunits have been described in mammals. Integrin family members are membrane receptors involved in cell adhesion and recognition in a variety of processes including embryogenesis, hemostasis, tissue repair, immune response and metastatic diffusion of tumor cells. This gene encodes a beta subunit. Multiple alternatively spliced transcript variants which encode different protein isoforms have been found for this gene.

integrin subunit beta 1

Integrins alpha-1/beta-1, alpha-2/beta-1, alpha-10/beta-1 and alpha-11/beta-1 are receptors for collagen. Integrins alpha-1/beta-1 and alpha-2/beta-2 recognize the proline-hydroxylated sequence G-F-P-G-E-R in collagen. Integrins alpha-2/beta-1, alpha-3/beta-1, alpha-4/beta-1, alpha-5/beta-1, alpha-8/beta-1, alpha-10/beta-1, alpha-11/beta-1 and alpha-V/beta-1 are receptors for fibronectin. Alpha-4/beta-1 recognizes one or more domains within the alternatively spliced CS-1 and CS-5 regions of fibronectin. Integrin alpha-5/beta-1 is a receptor for fibrinogen. Integrin alpha-1/beta-1, alpha-2/beta-1, alpha-6/beta-1 and alpha-7/beta-1 are receptors for lamimin. Integrin alpha-6/beta-1 (ITGA6:ITGB1) is present in oocytes and is involved in sperm-egg fusion (By similarity).
Integrin alpha-4/beta-1 is a receptor for VCAM1. It recognizes the sequence Q-I-D-S in VCAM1. Integrin alpha-9/beta-1 is a receptor for VCAM1, cytotactin and osteopontin. It recognizes the sequence A-E-I-D-G-I-E-L in cytotactin. Integrin alpha-3/beta-1 is a receptor for epiligrin, thrombospondin and CSPG4. Alpha-3/beta-1 may mediate with LGALS3 the stimulation by CSPG4 of endothelial cells migration. Integrin alpha-V/beta-1 is a receptor for vitronectin. Beta-1 integrins recognize the sequence R-G-D in a wide array of ligands. When associated with alpha-7 integrin, regulates cell adhesion and laminin matrix deposition. Involved in promoting endothelial cell motility and angiogenesis. Involved in osteoblast compaction through the fibronectin fibrillogenesis cell-mediated matrix assembly process and the formation of mineralized bone nodules. May be involved in up-regulation of the activity of kinases such as PKC via binding to KRT1. Together with KRT1 and RACK1, serves as a platform for SRC activation or inactivation. Plays a mechanistic adhesive role during telophase, required for the successful completion of cytokinesis. Integrin alpha-3/beta-1 provides a docking site for FAP (seprase) at invadopodia plasma membranes in a collagen-dependent manner and hence may participate in the adhesion, formation of invadopodia and matrix degradation processes, promoting cell invasion. ITGA4:ITGB1 binds to fractalkine (CX3CL1) and may act as its coreceptor in CX3CR1-dependent fractalkine signaling (PubMed:23125415, PubMed:24789099).
ITGA4:ITGB1 and ITGA5:ITGB1 bind to PLA2G2A via a site (site 2) which is distinct from the classical ligand-binding site (site 1) and this induces integrin conformational changes and enhanced ligand binding to site 1 (PubMed:18635536, PubMed:25398877).
ITGA5:ITGB1 acts as a receptor for fibrillin-1 (FBN1) and mediates R-G-D-dependent cell adhesion to FBN1 (PubMed:12807887, PubMed:17158881).
ITGA5:ITGB1 is a receptor for IL1B and binding is essential for IL1B signaling (PubMed:29030430).
ITGA5:ITGB3 is a receptor for soluble CD40LG and is required for CD40/CD40LG signaling (PubMed:31331973).
Plays an important role in myoblast differentiation and fusion during skeletal myogenesis (By similarity).
Isoform 2
Interferes with isoform 1 resulting in a dominant negative effect on cell adhesion and migration (in vitro).
Isoform 5
Isoform 5 displaces isoform 1 in striated muscles.
(Microbial infection) Integrin ITGA2:ITGB1 acts as a receptor for Human echoviruses 1 and 8.
(Microbial infection) Acts as a receptor for Cytomegalovirus/HHV-5.
(Microbial infection) Acts as a receptor for Epstein-Barr virus/HHV-4.
(Microbial infection) Integrin ITGA5:ITGB1 acts as a receptor for Human parvovirus B19.
(Microbial infection) Integrin ITGA2:ITGB1 acts as a receptor for Human rotavirus.
(Microbial infection) Acts as a receptor for Mammalian reovirus.
(Microbial infection) In case of HIV-1 infection, integrin ITGA5:ITGB1 binding to extracellular viral Tat protein seems to enhance angiogenesis in Kaposi's sarcoma lesions.
(Microbial infection) Interacts with CotH proteins expressed by fungi of the order mucorales, the causative agent of mucormycosis, which plays an important role in epithelial cell invasion by the fungi (PubMed:32487760).
Integrin ITGA3:ITGB1 may act as a receptor for R.delemar CotH7 in alveolar epithelial cells, which may be an early step in pulmonary mucormycosis disease progression (PubMed:32487760).

Axon extensionIEA:Ensembl
B cell differentiation1 PublicationIC:BHF-UCL
Basement membrane organizationIEA:Ensembl
Calcium-independent cell-matrix adhesionManual Assertion Based On ExperimentIGI:MGI
Cardiac muscle cell differentiationIEA:Ensembl
CD40 signaling pathwayManual Assertion Based On ExperimentIDA:UniProtKB
Cell adhesionManual Assertion Based On ExperimentIDA:UniProtKB
Cell adhesion mediated by integrinManual Assertion Based On ExperimentIDA:UniProtKB
Cell fate specificationIEA:Ensembl
Cell migrationManual Assertion Based On ExperimentIBA:GO_Central
Cell migration involved in sprouting angiogenesisIEA:Ensembl
Cell projection organizationISS:ARUK-UCL
Cell-cell adhesion mediated by integrinManual Assertion Based On ExperimentIEP:BHF-UCL
Cell-matrix adhesionManual Assertion Based On ExperimentIMP:UniProtKB
Cell-substrate adhesionManual Assertion Based On ExperimentIMP:UniProtKB
Cellular defense responseManual Assertion Based On ExperimentTAS:ProtInc
Cellular response to low-density lipoprotein particle stimulusISS:UniProtKB
Dendrite morphogenesisIEA:Ensembl
Establishment of mitotic spindle orientationManual Assertion Based On ExperimentIMP:ARUK-UCL
Formation of radial glial scaffoldsIEA:Ensembl
G1/S transition of mitotic cell cycleIEA:Ensembl
Germ cell migrationIEA:Ensembl
Heterotypic cell-cell adhesionManual Assertion Based On ExperimentIMP:UniProtKB
Homophilic cell adhesion via plasma membrane adhesion moleculesManual Assertion Based On ExperimentTAS:ProtInc
In utero embryonic developmentIEA:Ensembl
Integrin-mediated signaling pathwayManual Assertion Based On ExperimentIDA:UniProtKB
Lamellipodium assemblyISS:ARUK-UCL
Leukocyte cell-cell adhesionManual Assertion Based On ExperimentIDA:BHF-UCL
Leukocyte tethering or rollingManual Assertion Based On ExperimentIMP:UniProtKB
Maintenance of blood-brain barrier1 PublicationNAS:ARUK-UCL
Mesodermal cell differentiationManual Assertion Based On ExperimentIEP:UniProtKB
Myoblast differentiationISS:UniProtKB
Myoblast fusionISS:UniProtKB
Negative regulation of anoikisManual Assertion Based On ExperimentIMP:UniProtKB
Negative regulation of cell differentiationIEA:Ensembl
Negative regulation of Rho protein signal transductionIEA:Ensembl
PhagocytosisISS:ARUK-UCL
Positive regulation of angiogenesisManual Assertion Based On ExperimentIMP:BHF-UCL
Positive regulation of apoptotic processManual Assertion Based On ExperimentIGI:MGI
Positive regulation of cell migrationISS:UniProtKB
Positive regulation of cell population proliferationIEA:Ensembl
Positive regulation of fibroblast migrationManual Assertion Based On ExperimentIDA:ARUK-UCL
Positive regulation of glutamate uptake involved in transmission of nerve impulseISS:ARUK-UCL
Positive regulation of GTPase activityManual Assertion Based On ExperimentIMP:UniProtKB
Positive regulation of protein kinase B signalingManual Assertion Based On ExperimentIDA:BHF-UCL
Positive regulation of protein localization to plasma membraneManual Assertion Based On ExperimentIDA:UniProtKB
Positive regulation of signaling receptor activityManual Assertion Based On ExperimentIDA:BHF-UCL
Positive regulation of wound healingManual Assertion Based On ExperimentIDA:ARUK-UCL
Reactive gliosisISS:ARUK-UCL
Receptor internalizationISS:UniProtKB
Regulation of cell cycleIEA:Ensembl
Regulation of collagen catabolic processManual Assertion Based On ExperimentIDA:UniProtKB
Regulation of inward rectifier potassium channel activityISS:ARUK-UCL
Regulation of spontaneous synaptic transmissionISS:ARUK-UCL
Sarcomere organizationIEA:Ensembl
Visual learningIEA:Ensembl

Cell membrane; Cell projection, invadopodium membrane; Cell projection, ruffle membrane; Recycling endosome; Melanosome; Cleavage furrow; Cell projection, lamellipodium; Cell projection, ruffle; Cell junction, focal adhesion; Cell surface. Isoform 2 does not localize to focal adhesions. Highly enriched in stage I melanosomes. Located on plasma membrane of neuroblastoma NMB7 cells. In a lung cancer cell line, in prometaphase and metaphase, localizes diffusely at the membrane and in a few intracellular vesicles. In early telophase, detected mainly on the matrix-facing side of the cells. By mid-telophase, concentrated to the ingressing cleavage furrow, mainly to the basal side of the furrow. In late telophase, concentrated to the extending protrusions formed at the opposite ends of the spreading daughter cells, in vesicles at the base of the lamellipodia formed by the separating daughter cells. Colocalizes with ITGB1BP1 and metastatic suppressor protein NME2 at the edge or peripheral ruffles and lamellipodia during the early stages of cell spreading on fibronectin or collagen. Translocates from peripheral focal adhesions sites to fibrillar adhesions in a ITGB1BP1-dependent manner. Enriched preferentially at invadopodia, cell membrane protrusions that correspond to sites of cell invasion, in a collagen-dependent manner. Localized at plasma and ruffle membranes in a collagen-independent manner.
Isoform 5: Cell membrane, sarcolemma; Cell junction. In cardiac muscle, isoform 5 is found in costameres and intercalated disks.

Extracellular: 21-728
Helical: 729-751
Cytoplasmic: 752-798

The cysteine residues are involved in intrachain disulfide bonds.