| Laminin, an extracellular protein, is a major component of the basement membrane. It is thought to mediate the attachment, migration, and organization of cells into tissues during embryonic development by interacting with other extracellular matrix components. It is composed of three subunits, alpha, beta, and gamma, which are bound to each other by disulfide bonds into a cross-shaped molecule. This gene encodes the alpha 2 chain, which constitutes one of the subunits of laminin 2 (merosin) and laminin 4 (s-merosin). Mutations in this gene have been identified as the cause of congenital merosin-deficient muscular dystrophy. Two transcript variants encoding different proteins have been found for this gene. [provided by RefSeq, Jul 2008],disease:Defects in LAMA2 are the cause of merosin-deficient congenital muscular dystrophy type 1A (MDC1A) [MIM:607855]. MDC1A is characterized by difficulty walking, hypotonia, proximal weakness, hyporeflexia, and white matter hypodensity on MRI.,domain:Domains VI, IV and G are globular.,domain:The alpha-helical domains I and II are thought to interact with other laminin chains to form a coiled coil structure.,function:Binding to cells via a high affinity receptor, laminin is thought to mediate the attachment, migration and organization of cells into tissues during embryonic development by interacting with other extracellular matrix components.,similarity:Contains 1 laminin N-terminal domain.,similarity:Contains 17 laminin EGF-like domains.,similarity:Contains 2 laminin IV type A domains.,similarity:Contains 5 laminin G-like domains.,subcellular location:Major component.,subunit:Laminin is a complex glycoprotein, consisting of three different polypeptide chains (alpha, beta, gamma), which are bound to each other by disulfide bonds into a cross-shaped molecule comprising one long and three short arms with globules at each end. Alpha-2 is a subunit of laminin-2 (merosin) and laminin-4 (S-merosin).,tissue specificity:Placenta, striated muscle, peripheral nerve, cardiac muscle, pancreas, lung, spleen, kidney, adrenal gland, skin, testis, meninges, choroid plexus, and some other regions of the brain, not in liver, thymus and bone., |
