integrin alpha-7 (ITGA7)

Function: - associates with integrin beta-1 (integrin alpha-7/beta-1) - isoform alpha-7X2B & isoform alpha-7X1B promote myoblast migration on laminin 1 & laminin 2/4, but isoform alpha-7X1B is less active on laminin 1 (in vitro) Structure: - composed of an heavy & a light chain linked by a disulfide bond - ADP-ribosylated on at least two sites of the extracellular domain in skeletal myotubes (putative) - belongs to the integrin alpha chain family - contains 7 FG-GAP repeats Compartment: membrane Alternative splicing: - named isoforms=12 - additional isoforms seem to exist - at least 5 alternatively spliced domains, 3 extracellular (X1, X2 & D) & 3 cytoplasmic (A, B & C) Expression: - isoforms containing segment A are predominantly expressed in skeletal muscle - isoforms containing segment B are abundantly expressed in skeletal muscle, moderately in cardiac muscle, small intestine, colon, ovary & prostate & weakly in lung & testes - isoforms containing segment X2D are expressed at low levels in fetal & adult skeletal muscle & in cardiac muscle, but are not detected in myoblasts & myotubes - in muscle fibers isoforms containing segment A & B are expressed at myotendinous & neuromuscular junctions - isoforms containing segment C are expressed at neuromuscular junctions & at extrasynaptic sites - isoforms containing segments X1 or X2 or, at low levels - X1X2 isoforms are expressed in fetal & adult skeletal muscle (myoblasts & myotubes) & cardiac muscle - in renewing intestinal epithelium, expression of isoforms containing segment B correlates with the onset of enterocytic differentiation Pathology: - defects in ITGA7 are associated with congenital myopathy due to ITGA7 defect

General

Ca+2 binding protein integrin-alpha

Properties

SIZE: entity length = 1181 aa MW = 129 kD COMPARTMENT: cellular membrane MOTIF: signal sequence {1-33} FG-GAP {50-87} MOTIF: N-glycosylation site {N86} cysteine residue {C94} MODIFICATION: cysteine residue {C103} cysteine residue {C103} MODIFICATION: cysteine residue {C94} FG-GAP {122-154} MOTIF: cysteine residue {C140} MODIFICATION: cysteine residue {C163} cysteine residue {C163} MODIFICATION: cysteine residue {C140} cysteine residue {C184} MODIFICATION: cysteine residue {C197} FG-GAP {194-224} MOTIF: cysteine residue {C197} MODIFICATION: cysteine residue {C184} FG-GAP {305-341} FG-GAP {362-400} MOTIF: Ca+2-binding site SITE: 372-380 FG-GAP {423-459} MOTIF: Ca+2-binding site SITE: 434-442 FG-GAP {481-521} MOTIF: Ca+2-binding site SITE: 492-500 cysteine residue {C539} MODIFICATION: cysteine residue {C546} cysteine residue {C546} MODIFICATION: cysteine residue {C539} cysteine residue {C552} MODIFICATION: cysteine residue {C615} cysteine residue {C615} MODIFICATION: cysteine residue {C552} cysteine residue {C681} MODIFICATION: cysteine residue {C687} cysteine residue {C687} MODIFICATION: cysteine residue {C681} cysteine residue {C781} MODIFICATION: cysteine residue {C792} N-glycosylation site {N786} cysteine residue {C792} MODIFICATION: cysteine residue {C781} cysteine residue {C939} MODIFICATION: cysteine residue {C-INTERCHAIN} arginine-rich region {953-958} MOTIF: arginine residue (SEVERAL) N-glycosylation site {N989} cysteine residue {C1001} MODIFICATION: cysteine residue {C1006} cysteine residue {C1006} MODIFICATION: cysteine residue {C1001} N-glycosylation site {N1025} N-glycosylation site {N1045} transmembrane domain {1083-1103} GFFKR {1107-1111} D-X-H-P {1157-1176} MOTIF: consensus repeat {1157-1160} SEQUENCE-IS: D-X-H-P consensus repeat {1165-1168} SEQUENCE-IS: D-X-H-P consensus repeat {1173-1176} SEQUENCE-IS: D-X-H-P

Database Correlations

OMIM 600536 UniProt Q13683 PFAM correlations Entrez Gene 3679 Kegg hsa:3679