LAMB2

Laminins, a family of extracellular matrix glycoproteins, are the major noncollagenous constituent of basement membranes. They have been implicated in a wide variety of biological processes including cell adhesion, differentiation, migration, signaling, neurite outgrowth and metastasis. Laminins, composed of 3 non identical chains: laminin alpha, beta and gamma (formerly A, B1, and B2, respectively), form a cruciform structure consisting of 3 short arms, each formed by a different chain, and a long arm composed of all 3 chains. Each laminin chain is a multidomain protein encoded by a distinct gene. Several isoforms of each chain have been described. Different alpha, beta and gamma chain isomers combine to give rise to different heterotrimeric laminin isoforms which are designated by Arabic numerals in the order of their discovery, i.e. alpha1beta1gamma1 heterotrimer is laminin 1. The biological functions of the different chains and trimer molecules are largely unknown, but some of the chains have been shown to differ with respect to their tissue distribution, presumably reflecting diverse functions in vivo. This gene encodes the beta chain isoform laminin, beta 2. The beta 2 chain contains the 7 structural domains typical of beta chains of laminin, including the short alpha region. However, unlike beta 1 chain, beta 2 has a more restricted tissue distribution. It is enriched in the basement membrane of muscles at the neuromuscular junctions, kidney glomerulus and vascular smooth muscle. Transgenic mice in which the beta 2 chain gene was inactivated by homologous recombination, showed defects in the maturation of neuromuscular junctions and impairment of glomerular filtration. Alternative splicing involving a non consensus 5' splice site (gc) in the 5' UTR of this gene has been reported. It was suggested that inefficient splicing of this first intron, which does not change the protein sequence, results in a greater abundance of the unspliced form of the transcript than the spliced form. The full-length nature of the spliced transcript is not known. [provided by RefSeq, Aug 2011]

Description

Laminin subunit beta 2

Tissue specificity

Low tissue specificity

Subcell location

Vesicles, Cytosol

Predicted location

Intracellular, Secreted to extracellular matrix

Protein family

Disease related genes
Human disease related genes
Mapped to neXtProt
Mapped to UniProt SWISS-PROT
Plasma proteins
Predicted intracellular proteins
Predicted secreted proteins
Protein evidence (Ezkurdia et al 2014)
Protein evidence (Kim et al 2014)

Chromosome

3 (49121114 - 49133118)

Ensembl ID

ENSG00000172037  (ver. 103.38)

Orthologs

Mouse Lamb2: ENSMUSG00000052911

UniProt

P55268

neXtProt

NX_P55268

Human splice variants
Mouse splice variants

Protein structure