Laminin alpha1 globular domains 4-5 induce fetal development but are not vital for embryonic basement membrane assembly.

ABSTRACT: During early mouse embryogenesis, each laminin (Lm) chain of the first described Lm, a heterotrimer of alpha1, beta1, and gamma1 chains (Lm-1), is essential for basement membrane (BM) assembly, which is required for pregastrulation development. Individual domains may have other functions, not necessarily structural. The cell binding C terminus of Lm alpha1 chain contains five Lm globular (LG) domains. In vitro, alpha1LG1-3 domains bind integrins, and alpha1LG4 binds dystroglycan, heparin, and sulfatides. A prevailing hypothesis is that alpha1LG4 is crucial as a structural domain for BM assembly, whereas integrin-binding sites conduct signaling. The in vivo role of alpha1LG4-5 (also called E3) has not been studied. Mice lacking alpha1LG4-5 were therefore made. Null embryos implanted, but pr

SUBMITTER: Scheele S 

PROVIDER: S-EPMC545491 | biostudies-literature | 2005 Feb

REPOSITORIES: biostudies-literature