Lamininbinding

Laminin-binding refers to interactions between laminin, an extracellular matrix glycoprotein in basement membranes, and cell-surface receptors or other matrix components. Laminin is a heterotrimer with globular domains; laminin-binding drives cell adhesion, migration, differentiation, and tissue organization.

Major laminin-binding receptors include integrins such as α3β1 and α6β4 that recognize laminin in the basement membrane; dystroglycan, part of the dystrophin-glycoprotein complex, binds laminin via its heavily glycosylated α-dystroglycan subunit; these interactions anchor cells to the matrix and activate intracellular signaling pathways (FAK, MAPK). Additional laminin-binding receptors include the 37/67 kDa laminin receptor (LamR, encoded by RPSA) which binds laminin at the cell surface and is involved in adhesion, translation, and signaling; heparan sulfate proteoglycans also contribute by binding laminin and aiding localization.

The glycosylation state of α-dystroglycan is a critical determinant of laminin binding; defects cause muscular dystrophies and basement membrane defects. Integrin-mediated binding can activate outside-in signaling and influence cytoskeletal organization. LamR is multifunctional, with roles beyond adhesion, including participation in ribosome function and viral entry.

In development and tissue homeostasis, laminin-binding supports basement membrane assembly and compartmentalization. Pathological changes in laminin-binding are associated with cancer invasion, fibrosis, and muscular diseases; understanding laminin-binding informs strategies for tissue engineering and regenerative medicine.