{"metadata":{"accession":"PS52047","entry_id":null,"type":"domain","go_terms":null,"source_database":"profile","member_databases":null,"integrated":null,"hierarchy":null,"name":{"name":"Integrins beta chain EGF (I-EGF) domain profile","short":"I_EGF_2"},"description":[{"text":"<p>Integrins [[cite:PUB00000811]][[cite:PUB00001505]] are a large family of cell surface receptors that mediate cell\nto cell as well as cell to matrix adhesion. Some integrins recognize the R-G-D\nsequence in their extracellular matrix protein ligand.\nStructurally, integrins consist of a dimer of an alpha and a beta chain. Each\nsubunit has a large N-terminal extracellular domain followed by a\ntransmembrane domain and a short C-terminal cytoplasmic region. Some receptors\nshare a common beta chain while having different alpha chains. The sequence of\na number of different beta chains has been determined and are listed below:\n\n - Integrin beta-1, which  associates with alpha-1 to form a laminin receptor,\n   with alpha-2 to form a  collagen receptor, with  alpha-4  to  interact with\n   VCAM-1, with alpha-5 to form a fibronectin receptor, and with alpha-8.\n - Integrin beta-2, which  associates with alpha-L (LFA-1)  to  interact  with\n   ICAM-1, and with alpha-M (MAC-1) or alpha-X  (p150,95) to form the receptor\n   for the iC3b fragment of the third complement component.\n - Integrin beta-3, which associates with alpha-IIB  to  form  a  receptor for\n   fibrinogen,  fibronectin,  vitronectin and VWF, and with alpha-V  to form a\n   vitronectin receptor.\n - Integrin beta-4, which associates with alpha-6.\n - Integrin beta-5, which associates with alpha-V.\n - Integrin beta-6 [[cite:PUB00002561]].\n - Integrin beta-7 [[cite:PUB00002637]].\n - Integrin beta-8, which associates with alpha-V [[cite:PUB00002660]].\n - The Drosophila myospheroid protein, a probable integrin beta chain.\n\nThe C-terminus of the extracellular region of all the integrin beta chains has\nfour cysteine-rich tandem repeats of forty amino acids, which are variants of\nthe EGF-like domain, termed integrin- or I-EGF domains. The\nI-EGF domain is a small globular domain mainly composed by loops with a small\nanti-parallel beta-sheet constituted of two beta-strands (see {PDB:1L3Y}. The\nstructure is stabilized by four disulfide bonds between the first and fifth,\nsecond and fourth, third and sixth, and seventh and eighth Cys residues. Three\ndisulfide bonds are shared with classical EGF-like domains. The disulfide\nunique to I-EGF domains links the N-terminus to the turn between the two beta-\nstrands. Compared to classical EGF-like modules with three disulfide bonds,\nthe I-EGF module is less elongated, with a nosecone-like shape. The anti-\nparallel sheet between the two beta-strands is shortened because four highly\nconserved residues among classical EGF-like modules are deleted in I-EGF\nmodules. I-EGF repeats in the integrin beta subunit stalk region relay\nactivation signals to the ligand-binding headpiece [[cite:PUB00002660]][[cite:PUB00026914]].\n\nWe have developed a pattern from a section of the I-EGF domain that includes\nfive of the conserved cysteines. We also developed a profile which covers the\nentire I-EGF domain.</p>","llm":false,"checked":false,"updated":false}],"wikipedia":null,"literature":{"PUB00002561":{"PMID":2365683,"ISBN":null,"volume":"265","issue":"20","year":1990,"title":"Complete amino acid sequence of a novel integrin beta subunit (beta 6) identified in epithelial cells using the polymerase chain reaction.","URL":null,"raw_pages":"11502-7","medline_journal":"J Biol Chem","ISO_journal":"J. Biol. Chem.","authors":["Sheppard D","Rozzo C","Starr L","Quaranta V","Erle DJ","Pytela R."],"DOI_URL":"http://intl.jbc.org/cgi/content/abstract/265/20/11502"},"PUB00002660":{"PMID":1918072,"ISBN":null,"volume":"266","issue":"29","year":1991,"title":"Cloning and expression of a divergent integrin subunit beta 8.","URL":null,"raw_pages":"19650-8","medline_journal":"J Biol Chem","ISO_journal":"J. Biol. Chem.","authors":["Moyle M","Napier MA","McLean JW."],"DOI_URL":"http://intl.jbc.org/cgi/reprint/266/29/19650.pdf"},"PUB00026914":{"PMID":11896403,"ISBN":null,"volume":"9","issue":"4","year":2002,"title":"Cysteine-rich module structure reveals a fulcrum for integrin rearrangement upon activation.","URL":null,"raw_pages":"282-7","medline_journal":"Nat Struct Biol","ISO_journal":"Nat. Struct. Biol.","authors":["Beglova N","Blacklow SC","Takagi J","Springer TA."],"DOI_URL":"http://dx.doi.org/10.1038/nsb779"},"PUB00000811":{"PMID":3028640,"ISBN":null,"volume":"48","issue":"4","year":1987,"title":"Integrins: a family of cell surface receptors.","URL":null,"raw_pages":"549-54","medline_journal":"Cell","ISO_journal":"Cell","authors":["Hynes RO."],"DOI_URL":"http://dx.doi.org/10.1016/0092-8674(87)90233-9"},"PUB00002637":{"PMID":2040616,"ISBN":null,"volume":"266","issue":"17","year":1991,"title":"Complete amino acid sequence of an integrin beta subunit (beta 7) identified in leukocytes.","URL":null,"raw_pages":"11009-16","medline_journal":"J Biol Chem","ISO_journal":"J. Biol. Chem.","authors":["Erle DJ","Ruegg C","Sheppard D","Pytela R."],"DOI_URL":"http://intl.jbc.org/cgi/reprint/266/17/11009.pdf"},"PUB00001505":{"PMID":2199285,"ISBN":null,"volume":"4","issue":"11","year":1990,"title":"Integrins and other cell adhesion molecules.","URL":null,"raw_pages":"2868-80","medline_journal":"FASEB J","ISO_journal":"FASEB J.","authors":["Albelda SM","Buck CA."],"DOI_URL":"http://www.fasebj.org/cgi/content/abstract/4/11/2868"}},"set_info":null,"overlaps_with":null,"counters":{"subfamilies":0,"domain_architectures":0,"interactions":0,"matches":36929,"pathways":0,"proteins":13478,"proteomes":1215,"sets":0,"structural_models":{"alphafold":11372,"bfvd":0},"structures":135,"taxa":4211},"entry_annotations":{},"cross_references":{},"is_llm":false,"is_reviewed_llm":false,"is_updated_llm":false,"representative_structure":null}}