| First Author | Yu H | Year | 2003 |
| Journal | Biochem J | Volume | 371 |
| Issue | Pt 2 | Pages | 289-99 |
| PubMed ID | 12519075 | Mgi Jnum | J:83029 |
| Mgi Id | MGI:2656476 | Doi | 10.1042/BJ20021500 |
| Citation | Yu H, et al. (2003) Beta1 integrin and alpha-dystroglycan binding sites are localized to different laminin-G-domain-like (LG) modules within the laminin alpha5 chain G domain. Biochem J 371(Pt 2):289-99 |
| abstractText | Laminins are a group of extracellular-matrix proteins important in development and disease. They are heterotrimers, and specific domains in the different chains have specialized functions. The G domain of the alpha5 chain has now been produced in transfected mammalian cells as single modules and two tandem arrays, alpha5LG1-3 and alpha5LG4-5 (LG is laminin G domain-like). Using these fragments we produced specific polyclonal antibodies functional in immunoblotting and immunofluorescence studies and in solid-phase assays. Both alpha5LG tandem arrays had physiologically relevant affinities for sulphated ligands such as heparin and sulphatides. Cells adhered to these fragments and acquired a spread morphology when plated on alpha5LG1-3. Binding of integrins alpha3beta1 and alpha6beta1 was localized to the alpha5LG1-3 modules, and alpha-dystroglycan binding was localized to the alpha5LG4-5 modules, thus locating these activities to different LG modules within the laminin alpha5 G domain. However, both these activities were of relatively low affinity, indicating that integrin-mediated cell adhesion to the laminin 10/11 alpha5G domain depends on contributions from the other chains of the heterotrimer and that high-affinity alpha-dystroglycan binding could be dependent on specific Ca(2+)-ion-co-ordinating amino acids absent from alpha5LG4-5. |
