High impact information on Lamb2

• Synthesis and assembly of the synaptic cleft protein S-laminin by cultured cells [1].
• S-laminin was detected intracellularly in both cell types, in extracellular matrix of muscle cells, and in two immunochemically distinct forms [1].
• S-laminin, a homologue of the B1 chain of laminin, is concentrated in a subset of basal laminae (BLs), including the BL at the skeletal neuromuscular junction and bears an adhesive site for motoneuron-like cells [1].
• Thus, the cDNA contains sufficient information to permit assembly, secretion, and post-translational modification of S-laminin [1].
• We show that several muscle- and glia-like cell lines synthesize and secrete S-laminin as well as the A, B1, and B2 subunits of the conventional laminin trimer [1].

Biological context of Lamb2

• Analysis of tunicamycin-treated cells indicated that N-linked glycosylation is required neither for the selective association of S-laminin with B2 and A subunits nor for the distinction between two forms of S-laminin [1].
• Additionally the gene expression of other extracellular matrix proteins, viz., collagen type III, fibronectin, osteopontin, proteoglycan NG2, laminin gamma1 and S-laminin, was also markedly increased, as determined by competitive RT-PCR after 14 days of MNNG exposure [2].

Anatomical context of Lamb2

• PURPOSE: The authors previously hypothesized that laminin beta 2 (S-laminin) plays a role in directing photoreceptor development [3].
• S-laminin is concentrated in the synaptic cleft at the neuromuscular junction and contains a site that is adhesive for motor neurons, suggesting that it may influence neuromuscular development [4].
• In this study, we have used monoclonal antibodies to several of these subunits, including S-laminin, laminin B2, and laminin B1, to study these proteins in tail artery, superior mesenteric artery, and aorta of rats [5].
• To investigate whether smooth muscle cells can produce S-laminin, laminin B2, and laminin B1, smooth muscle cells from the superior mesenteric artery were grown in culture and laminin subunit expression determined [5].
• S-laminin and N-acetylgalactosamine located at the synaptic basal lamina of skeletal muscle are involved in synaptic recognition by growing neurites [6].

Other interactions of Lamb2

• The same pattern of S-laminin immunostaining was seen during early culture in cells grown on fibronectin, type IV collagen, or gelatin [5].

Analytical, diagnostic and therapeutic context of Lamb2

• S-laminin mRNA could readily be demonstrated in neonatal rat livers by Northern blot analysis, whereas A and M could not [7].
• Immunoblotting detected S-laminin in the conditioned medium from early cultured cells [5].

References