Sarcalumenin (SRL)

Sarcalumenin is a gene which encodes a 160-kD glycoprotein protein involved in calcium signaling.Muscle contraction is triggered by the release of calcium from the sarcoplasmic reticulum, whereas muscle relaxation is achieved by rapid reuptake of calcium from the cytosol into the lumen of the sarcoplasmic reticulum. Sequestration of calcium in the lumen of the sarcoplasmic reticulum is also an essential step in the overall contraction-relaxation cycle of muscle cells. The rabbit sarcoplasmic reticulum contains 2 immunochemically related glycoproteins with apparent molecular masses of 53 and 160 kD.The deduced 160-kD glycoprotein contains an N-terminal signal sequence and a 453-amino acid C-terminal sequence that together form a protein that is identical to the 53-kD glycoprotein.