Sarcalumenin is a protein that in humans is encoded by the SRL gene.
Sarcalumenin is a calcium-binding protein that can be found in the sarcoplasmic reticulum of striated muscle. Sarcalumenin is partially responsible for calcium buffering in the lumen of the sarcoplasmic reticulum and helps out calcium pump proteins. Additionally, sarcalumenin is necessary for keeping a normal sinus rhythm during both aerobic and anaerobic exercise activity. Sarcalumenin is a calcium-binding glycoprotein composed of 473 acidic amino acids with a molecular weight of 160 KDa. Together along with other luminal calcium buffer proteins, sarcalumenin plays an important role in regulation of calcium uptake and release during excitation-contraction coupling (ECC) in muscle fibers.