Component of the sarcoglycan complex, a subcomplex of the dystrophin-glycoprotein complex which forms a link between the F-actin cytoskeleton and the extracellular matrix. Identified in all tissues tested. Expression highest in lung and placenta, moderate in brain, heart and skeletal muscle, low in kidney and liver. Also detected in embryo. N-glycosylated. Ubiquitinated, leading to its degradation by the proteasome. Belongs to the sarcoglycan alpha/epsilon family. Truncated N-terminus. Truncated N-terminus. Truncated N-terminus.