Laminin Beta 4 (LAMb4)

Laminins (LN)are the major non-collagenous component of the basal lamina, such as those on which cells of an epithelium sit.They are a family of glycoproteins that are an integral part of the structural scaffolding of basement membranes in almost every animal tissue. Laminins are secreted and incorporated into cell-associated extracellular matrices.Dysfunctional structure of one particular laminin, laminin-2, is the cause of some forms of muscular dystrophy.

Laminin-2 is composed of an α2, a β1 and a γ1 chains. This laminin's distribution includes the brain and muscle fibers. In muscle, it binds to alpha dystroglycan via the G domain, and via the other end binds to the extracellular matrix. Progeria is the result of a defect in the prolaminin receptor that prevents the cleaving and activation of prolaminin into laminin.