Dystroglycan loss disrupts polarity and beta-casein induction in mammary epithelial cells by perturbing laminin anchoring.

ABSTRACT: Precise contact between epithelial cells and their underlying basement membrane is crucial to the maintenance of tissue architecture and function. To understand the role that the laminin receptor dystroglycan (DG) plays in these processes, we assayed cell responses to laminin-111 following conditional ablation of DG gene (Dag1) expression in cultured mammary epithelial cells. Strikingly, DG loss disrupted laminin-111-induced polarity and beta-casein production, and abolished laminin assembly at the step of laminin binding to the cell surface. Dystroglycan re-expression restored these deficiencies. Investigations of the mechanism revealed that DG cytoplasmic sequences were not necessary for laminin assembly and signaling, and only when the entire mucin domain of extracellular DG was deleted

SUBMITTER: Weir ML 

PROVIDER: S-EPMC2996718 | biostudies-literature | 2006 Oct

REPOSITORIES: biostudies-literature