ITGB8

Integrin, beta 8
Identifiers
Symbol	ITGB8
External IDs	OMIM: 604160 MGI: 1338035 HomoloGene: 18567 GeneCards: ITGB8 Gene
Gene ontology Molecular function • receptor activity • extracellular matrix protein binding Cellular component • plasma membrane • integrin complex • cell surface • integrin alphav-beta8 complex • extracellular exosome Biological process • ganglioside metabolic process • cell adhesion • cell-matrix adhesion • integrin-mediated signaling pathway • positive regulation of gene expression • negative regulation of gene expression • extracellular matrix organization • cartilage development • placenta blood vessel development Sources: Amigo / QuickGO
RNA expression pattern
More reference expression data
Orthologs
Species	Human	Mouse
Entrez	3696	320910
Ensembl	ENSG00000105855	ENSMUSG00000025321
UniProt	P26012	Q0VBD0
RefSeq (mRNA)	NM_002214	NM_177290
RefSeq (protein)	NP_002205	NP_796264
Location (UCSC)	Chr 7: 20.33 – 20.42 Mb	Chr 12: 119.16 – 119.24 Mb
PubMed search

Integrin beta-8 is a protein that in humans is encoded by the ITGB8 gene.^[1]

Function

This gene is a member of the integrin beta chain family and encodes a single-pass type I membrane protein with a VWFA domain and four cysteine-rich repeats. This protein noncovalently binds to an alpha subunit to form a heterodimeric integrin complex. In general, integrin complexes mediate cell-cell and cell-extracellular matrix interactions and this complex plays a role in human airway epithelial proliferation. Alternatively spliced variants which encode different protein isoforms have been described; however, not all variants have been fully characterized.^[1] Additionally, it has been shown to interact with RhoGDI1 to alter the activation of Rho GTPases to promote Glioblastoma cell invasiveness. Uncoupling the αvβ8-RhoGDI1 interaction has been seen to block GBM cell invasion by hyperactivating Rho GTPases.^[2]

Clinical significance

High expression levels of ITGB8 are associated with high angiogenic and poorly invasive glioblastoma tumors. Conversely low expression of ITGB8 correlates with highly invasive but low angiogenic tumors.^[3]

References

1. "Entrez Gene: ITGB8 integrin, beta 8".
2. Reyes SB, Narayanan AS, Lee HS, Tchaicha JH, Aldape KD, Lang FF, Tolias KF, McCarty JH (January 2012). "αvβ8 Integrin Interacts with RhoGDI1 to Regulate Rac1 and Cdc42 Activation and Drive Glioblastoma Cell Invasion". Mol Bio Cell 24 (4): 474–82. doi:10.1091/mbc.E12-07-0521. PMID 23283986.
3. Tchaicha JH, Reyes SB, Shin J, Hossain MG, Lang FF, McCarty JH (October 2011). "Glioblastoma Angiogenesis and Tumor Cell Invasiveness Are Differentially Regulated by {beta}8 Integrin". Cancer Res. 71 (20): 6371–81. doi:10.1158/0008-5472.CAN-11-0991. PMC 3193578. PMID 21859829.

Further reading

• Moyle M, Napier MA, McLean JW (1991). "Cloning and expression of a divergent integrin subunit beta 8.". J. Biol. Chem. 266 (29): 19650–8. PMID 1918072.
• Nishimura SL, Sheppard D, Pytela R (1994). "Integrin alpha v beta 8. Interaction with vitronectin and functional divergence of the beta 8 cytoplasmic domain.". J. Biol. Chem. 269 (46): 28708–15. PMID 7525578.
• Pilewski JM, Latoche JD, Arcasoy SM, Albelda SM (1997). "Expression of integrin cell adhesion receptors during human airway epithelial repair in vivo.". Am. J. Physiol. 273 (1 Pt 1): L256–63. PMID 9252563.
• "Toward a complete human genome sequence.". Genome Res. 8 (11): 1097–108. 1999. doi:10.1101/gr.8.11.1097. PMID 9847074.
• Cambier S, Mu DZ, O'Connell D, et al. (2001). "A role for the integrin alphavbeta8 in the negative regulation of epithelial cell growth.". Cancer Res. 60 (24): 7084–93. PMID 11156415.
• Mu D, Cambier S, Fjellbirkeland L, et al. (2002). "The integrin αvβ8 mediates epithelial homeostasis through MT1-MMP–dependent activation of TGF-β1". J. Cell Biol. 157 (3): 493–507. doi:10.1083/jcb.200109100. PMC 2173277. PMID 11970960.
• Jarad G, Wang B, Khan S, et al. (2003). "Fas activation induces renal tubular epithelial cell beta 8 integrin expression and function in the absence of apoptosis". J. Biol. Chem. 277 (49): 47826–33. doi:10.1074/jbc.M204901200. PMID 12324452.
• Strausberg RL, Feingold EA, Grouse LH, et al. (2003). "Generation and initial analysis of more than 15,000 full-length human and mouse cDNA sequences". Proc. Natl. Acad. Sci. U.S.A. 99 (26): 16899–903. doi:10.1073/pnas.242603899. PMC 139241. PMID 12477932.
• Scherer SW, Cheung J, MacDonald JR, et al. (2003). "Human Chromosome 7: DNA Sequence and Biology". Science 300 (5620): 767–72. doi:10.1126/science.1083423. PMC 2882961. PMID 12690205.
• Hillier LW, Fulton RS, Fulton LA, et al. (2003). "The DNA sequence of human chromosome 7". Nature 424 (6945): 157–64. doi:10.1038/nature01782. PMID 12853948.
• Fjellbirkeland L, Cambier S, Broaddus VC, et al. (2003). "Integrin αvβ8-Mediated Activation of Transforming Growth Factor-β Inhibits Human Airway Epithelial Proliferation in Intact Bronchial Tissue". Am. J. Pathol. 163 (2): 533–42. doi:10.1016/S0002-9440(10)63681-4. PMC 1868219. PMID 12875973.
• Rual JF, Venkatesan K, Hao T, et al. (2005). "Towards a proteome-scale map of the human protein-protein interaction network". Nature 437 (7062): 1173–8. doi:10.1038/nature04209. PMID 16189514.
• Yan W, Shao R (2006). "Transduction of a mesenchyme-specific gene periostin into 293T cells induces cell invasive activity through epithelial-mesenchymal transformation". J. Biol. Chem. 281 (28): 19700–8. doi:10.1074/jbc.M601856200. PMID 16702213.

External links

• ITGB8 Info with links in the Cell Migration Gateway