Sarcoglycan Beta (SGCb)

The sarcoglycans are a family of transmembrane proteins (α, β, γ, δ or ε) involved in the protein complex responsible for connecting the muscle fibre cytoskeleton to the extracellular matrix, preventing damage the muscle fibre sarcolemma through shearing forces.Mutations in the α, β, γ or δ genes (not ε) encoding these proteins can lead to the associated limb-girdle muscular dystrophy. The dystrophin-glycoprotein complex (DGC) is a multisubunit protein complex that spans the sarcolemma and provides structural linkage between the subsarcolemmal cytoskeleton and the extracellular matrix of muscle cells. There are 3 main subcomplexes of the DGC: the cytoplasmic proteins dystrophin and syntrophin (SNTA1), the alpha- and beta-dystroglycans, and the sarcoglycans.