Integrin beta-1 (ITGB1), also known as CD29, is a cell surface receptor that in humans is encoded by the ITGB1gene.[1] This integrin associates with integrins alpha 1 and 2 to form integrin complexes which function as collagen receptors. It also forms dimers with integrin alpha 3 to form integrin receptors for netrin 1 and reelin. These and other integrin beta 1 complexes have been historically known as very late activation (VLA) antigens.
Integrin beta-1 can exist as different isoforms via alternative splicing. Six alternatively spliced variants have been found for this gene which encode five proteins with alternate C-termini.[2] Integrin receptors exist as heterodimers, and greater than 20 different integrin heterodimeric receptors have been described. All integrins, alpha and beta forms, have large extracellular and short intracellular domains.[3] The cytoplasmic domain of integrin beta-1 binds to the actincytoskeleton.[4] Integrin beta-1 is the most abundant beta-integrin expressed and associates with at least 10 different integrin-alpha subunits.[3]
Function
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.[3] Integrins link the actincytoskeleton with the extracellular matrix and they transmit signals bidirectionally between the extracellular matrix and cytoplasmic domains.[5][6]
Beta-integrins are primarily responsible for targeting integrin dimers to the appropriate subcellular locations, which in adhesive cells is mainly focal adhesions.[4][7] Integrin beta-1 mutants lose the ability to target to sites of focal adhesions.[8][9]
Three novel isoforms of integrin beta-1 have been identified, termed beta-1B, beta-1C and beta-1D. Integrin beta-1B is transcribed when the proximal 26 amino acids of the cytoplasmic domain in exon 6 are retained and then succeeded by a 12 amino acid stretch from an adjacent intronic region.[10] The integrin beta-1B isoform appears to act as a dominant negative in that it inhibits cell adhesion.[11] A second integrin beta-1 isoform, termed beta-1C, was described to have an additional 48 amino acids appended to the 26 amino acids in the cytoplasmic domain;[12] the function of this isoform was an inhibitory one on DNA synthesis in the G1 phase of the cell cycle.[13] The third isoform, termed beta-1D, is a striated muscle-specific isoform, which replaces the canonical beta-1A isoform in cardiac and skeletal muscle cells. This isoform is produced from splicing into a novel additional exon between exons 6 and 7. The cytoplasmic domain of integrin beta-1D replaces the distal 21 amino acids (present in integrin beta-1A) with an alternative stretch of 24 amino acids (13 unique).[14][15]
In patients with sensitive-motor polyneuropathy, levels of integrin alpha-7B, integrin beta-1D and agrin were significantly reduced nearly to undetectable levels; and this corresponded with lower mRNA levels.[18]
↑Goodfellow PJ, Nevanlinna HA, Gorman P, Sheer D, Lam G, Goodfellow PN (Jan 1989). "Assignment of the gene encoding the beta-subunit of the human fibronectin receptor (beta-FNR) to chromosome 10p11.2". Annals of Human Genetics. 53 (Pt 1): 15–22. doi:10.1111/j.1469-1809.1989.tb01118.x. PMID2524991.
↑Akiyama SK, Yamada SS, Yamada KM, LaFlamme SE (Jun 1994). "Transmembrane signal transduction by integrin cytoplasmic domains expressed in single-subunit chimeras". The Journal of Biological Chemistry. 269 (23): 15961–4. PMID7515874.
↑Languino LR, Ruoslahti E (Apr 1992). "An alternative form of the integrin beta 1 subunit with a variant cytoplasmic domain". The Journal of Biological Chemistry. 267 (10): 7116–20. PMID1551917.
↑Meredith J, Takada Y, Fornaro M, Languino LR, Schwartz MA (Sep 1995). "Inhibition of cell cycle progression by the alternatively spliced integrin beta 1C". Science. 269 (5230): 1570–2. doi:10.1126/science.7545312. PMID7545312.
↑Zhidkova NI, Belkin AM, Mayne R (Sep 1995). "Novel isoform of beta 1 integrin expressed in skeletal and cardiac muscle". Biochemical and Biophysical Research Communications. 214 (1): 279–85. doi:10.1006/bbrc.1995.2285. PMID7545396.
↑ 15.015.1van der Flier A, Kuikman I, Baudoin C, van der Neut R, Sonnenberg A (Aug 1995). "A novel beta 1 integrin isoform produced by alternative splicing: unique expression in cardiac and skeletal muscle". FEBS Letters. 369 (2–3): 340–4. doi:10.1016/0014-5793(95)00814-p. PMID7544298.
↑Anastasi G, Cutroneo G, Trimarchi F, Santoro G, Bruschetta D, Bramanti P, Pisani A, Favaloro A (Dec 2004). "Evaluation of sarcoglycans, vinculin-talin-integrin system and filamin2 in alpha- and gamma-sarcoglycanopathy: an immunohistochemical study". International Journal of Molecular Medicine. 14 (6): 989–99. doi:10.3892/ijmm.14.6.989. PMID15547664.
↑Otey CA, Vasquez GB, Burridge K, Erickson BW (Oct 1993). "Mapping of the alpha-actinin binding site within the beta 1 integrin cytoplasmic domain". The Journal of Biological Chemistry. 268 (28): 21193–7. PMID7691808.
↑Lozahic S, Christiansen D, Manié S, Gerlier D, Billard M, Boucheix C, Rubinstein E (Mar 2000). "CD46 (membrane cofactor protein) associates with multiple beta1 integrins and tetraspans". European Journal of Immunology. 30 (3): 900–7. doi:10.1002/1521-4141(200003)30:3<900::AID-IMMU900>3.0.CO;2-X. PMID10741407.
↑Radford KJ, Thorne RF, Hersey P (May 1996). "CD63 associates with transmembrane 4 superfamily members, CD9 and CD81, and with beta 1 integrins in human melanoma". Biochemical and Biophysical Research Communications. 222 (1): 13–8. doi:10.1006/bbrc.1996.0690. PMID8630057.
↑ 23.023.1Mazzocca A, Carloni V, Sciammetta S, Cordella C, Pantaleo P, Caldini A, Gentilini P, Pinzani M (Sep 2002). "Expression of transmembrane 4 superfamily (TM4SF) proteins and their role in hepatic stellate cell motility and wound healing migration". Journal of Hepatology. 37 (3): 322–30. doi:10.1016/S0168-8278(02)00175-7. PMID12175627.
↑Wixler V, Geerts D, Laplantine E, Westhoff D, Smyth N, Aumailley M, Sonnenberg A, Paulsson M (Oct 2000). "The LIM-only protein DRAL/FHL2 binds to the cytoplasmic domain of several alpha and beta integrin chains and is recruited to adhesion complexes". The Journal of Biological Chemistry. 275 (43): 33669–78. doi:10.1074/jbc.M002519200. PMID10906324.
↑Loo DT, Kanner SB, Aruffo A (Sep 1998). "Filamin binds to the cytoplasmic domain of the beta1-integrin. Identification of amino acids responsible for this interaction". The Journal of Biological Chemistry. 273 (36): 23304–12. doi:10.1074/jbc.273.36.23304. PMID9722563.
↑ 28.028.1Lee HS, Millward-Sadler SJ, Wright MO, Nuki G, Al-Jamal R, Salter DM (Nov 2002). "Activation of Integrin-RACK1/PKCalpha signalling in human articular chondrocyte mechanotransduction". Osteoarthritis and Cartilage / OARS, Osteoarthritis Research Society. 10 (11): 890–7. doi:10.1053/joca.2002.0842. PMID12435334.
↑Liliental J, Chang DD (Jan 1998). "Rack1, a receptor for activated protein kinase C, interacts with integrin beta subunit". The Journal of Biological Chemistry. 273 (4): 2379–83. doi:10.1074/jbc.273.4.2379. PMID9442085.
↑Chang DD, Hoang BQ, Liu J, Springer TA (Mar 2002). "Molecular basis for interaction between Icap1 alpha PTB domain and beta 1 integrin". The Journal of Biological Chemistry. 277 (10): 8140–5. doi:10.1074/jbc.M109031200. PMID11741908.
↑Hadari YR, Arbel-Goren R, Levy Y, Amsterdam A, Alon R, Zakut R, Zick Y (Jul 2000). "Galectin-8 binding to integrins inhibits cell adhesion and induces apoptosis". Journal of Cell Science. 113 (13): 2385–97. PMID10852818.
↑Poinat P, De Arcangelis A, Sookhareea S, Zhu X, Hedgecock EM, Labouesse M, Georges-Labouesse E (Apr 2002). "A conserved interaction between beta1 integrin/PAT-3 and Nck-interacting kinase/MIG-15 that mediates commissural axon navigation in C. elegans". Current Biology. 12 (8): 622–31. doi:10.1016/S0960-9822(02)00764-9. PMID11967148.
↑Fournier HN, Dupé-Manet S, Bouvard D, Lacombe ML, Marie C, Block MR, Albiges-Rizo C (Jun 2002). "Integrin cytoplasmic domain-associated protein 1alpha (ICAP-1alpha ) interacts directly with the metastasis suppressor nm23-H2, and both proteins are targeted to newly formed cell adhesion sites upon integrin engagement". The Journal of Biological Chemistry. 277 (23): 20895–902. doi:10.1074/jbc.M200200200. PMID11919189.
↑Tapley P, Horwitz A, Buck C, Duggan K, Rohrschneider L (Mar 1989). "Integrins isolated from Rous sarcoma virus-transformed chicken embryo fibroblasts". Oncogene. 4 (3): 325–33. PMID2468126.
↑Horwitz A, Duggan K, Buck C, Beckerle MC, Burridge K (1986). "Interaction of plasma membrane fibronectin receptor with talin--a transmembrane linkage". Nature. 320 (6062): 531–3. doi:10.1038/320531a0. PMID2938015.
↑Tachibana I, Bodorova J, Berditchevski F, Zutter MM, Hemler ME (Nov 1997). "NAG-2, a novel transmembrane-4 superfamily (TM4SF) protein that complexes with integrins and other TM4SF proteins". The Journal of Biological Chemistry. 272 (46): 29181–9. doi:10.1074/jbc.272.46.29181. PMID9360996.
↑Han DC, Rodriguez LG, Guan JL (Jan 2001). "Identification of a novel interaction between integrin beta1 and 14-3-3beta". Oncogene. 20 (3): 346–57. doi:10.1038/sj.onc.1204068. PMID11313964.
Further reading
Evans JP (Jul 2001). "Fertilin beta and other ADAMs as integrin ligands: insights into cell adhesion and fertilization". BioEssays. 23 (7): 628–39. doi:10.1002/bies.1088. PMID11462216.
Armulik A (Jan 2002). "Splice variants of human beta 1 integrins: origin, biosynthesis and functions". Frontiers in Bioscience. 7: d219–27. doi:10.2741/armulik. PMID11779688.
Brakebusch C, Fässler R (Sep 2005). "beta 1 integrin function in vivo: adhesion, migration and more". Cancer Metastasis Reviews. 24 (3): 403–11. doi:10.1007/s10555-005-5132-5. PMID16258728.