SERCA2a: a key protein in the Ca²⁺ cycle of the heart failure

Calcium ion (Ca²⁺) cycle plays a crucial role in the contraction and relaxation of cardiomyocytes. The sarcoplasmic reticulum (SR) acts as an organelle for storing Ca²⁺, which mediated the release and re-uptake of Ca²⁺ during contraction and relaxation. Disorders of SR function lead to the dysfunction of Ca²⁺ cycle and myocardial cell function. The sarcoplasmic/endoplasmic reticulum Ca²⁺ ATPase 2a (SERCA2a) acts as a subtype of SERCA expressed in the heart, which mediates the contraction of cardiomyocytes and Ca²⁺ in the cytoplasm to re-enter into the SR. The rate of uptake of Ca²⁺ by the SR determines the rate of myocardial relaxation. The regulation of SERCA2a activity controls the contractility and relaxation of the heart, affecting cardiac function. The expression and activity of SERCA2a are reduced in failing hearts. Gene therapy by increasing the expression of SERCA2a in the heart has been proven effective. In addition, SERCA2a is regulated by a variety of factors, including transmembrane micropeptides, protein kinases, and post-translational modifications (PTMs). In this review, we discuss the regulatory factors of SERCA2a and provide new insights into future treatments and the direction of heart failure research. In addition, gene therapy for SERCA2a has recently emerged as therapeutic option and hence will be discussed in this review.