Phospholamban Regulates Nuclear Ca2+ Stores and Inositol 145-Trisphosphate Mediated Nuclear Ca2+ Cycling in Cardiomyocytes

摘要

AimsPhospholamban (PLB) is the key regulator of the cardiac Ca²⁺ pump (SERCA2a)-mediated sarcoplasmic reticulum Ca²⁺ stores. We recently reported that PLB is highly concentrated in the nuclear envelope (NE) from where it can modulate perinuclear Ca²⁺ handling of the cardiomyocytes (CMs). Since inositol 1,4,5-trisphosphate (IP3) receptor (IP3R) mediates nuclear Ca²⁺ release, we examined whether the nuclear pool of PLB regulates IP3-induced nuclear Ca²⁺ handling.