Laminin is a large molecular weight glycoprotein present only in basement membranes in almost every animal tissue. It is thought to mediate the attachment, migration and organisation of cells into tissues during embryonic development by interacting with other extracellular matrix components PMID:1975589. The polymerisation of laminin into a cell-associated network - a key step in basement membrane assembly - is mediated by the laminin amino-terminal (LN) domains at the tips of the three short arms of the laminin alpha-beta-gamma heterotrimer PMID:21311558.

Basement membrane assembly is a cooperative process in which laminins polymerise through their N-terminal domain (LN or domain VI) and anchor to the cell surface through their G domains. Netrins may also associate with this network through heterotypic LN domain interactions PMID:8349613. This leads to cell signalling through integrins and dystroglycan (and possibly other receptors) recruited to the adherent laminin. This LN domain dependent self-assembly is considered to be crucial for the integrity of basement membranes, as highlighted by genetic forms of muscular dystrophy containing the deletion of the LN module from the alpha 2 laminin chain PMID:7874173. The laminin N-terminal domain is found in all laminin and netrin subunits except laminin alpha 3A, alpha 4 and gamma 2.

INTERPRO:IPR008211, PFAM:PF00055