Sarcolipin


Sarcolipin is a micropeptide protein that in humans is encoded by the SLN gene.

Function

Ca2+-ATPases are transmembrane proteins that catalyze the ATP-dependent transport of Ca2+ from the cytosol into the lumen of the sarcoplasmic reticulum in muscle cells. The SLN gene encodes a small transmembrane proteolipid that regulates several sarcoplasmic reticulum Ca2+-ATPases by reducing the accumulation of Ca2+ in the sarcoplasmic reticulum without affecting the rate of ATP hydrolysis.
Ablation of sarcolipin increases atrial Ca2+ transient amplitudes and enhanced atrial contractility. Furthermore, atria from sarcolipin-null mice have blunted response to isoproterenol stimulation, implicating sarcolipin as a mediator of beta-adrenergic responses in atria.
Recently it has been shown that SLN is an important mediator of muscle based thermogenesis and loss of sarcolipin predisposes mice to diet-induced obesity thus suggesting its role in energy metabolism and regulation of weight gain

Interactions

SLN has been shown to interact with PLN and ATP2A1.