Phospholamban regulates nuclear Ca²⁺ stores and inositol 1,4,5-trisphosphate mediated nuclear Ca²⁺ cycling in cardiomyocytes.

ABSTRACT:

Aims

Phospholamban (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.

Methods and results

Fluo-4 based confocal Ca²⁺ imaging was performed to measure Ca²⁺ dynamics across both nucleus and cytosol in saponin-permeabilized CMs isolated from wild-type (WT) or PLB-knockout (PLB-KO)

SUBMITTER: Chen M 

PROVIDER: S-EPMC6205300 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature