Impaired myocellular Ca²⁺ cycling in protein phosphatase PP2A-B56α KO mice is normalized by β-adrenergic stimulation.

ABSTRACT: The activity of protein phosphatase 2A (PP2A) is determined by the expression and localization of the regulatory B-subunits. PP2A-B56α is the dominant isoform of the B'-family in the heart. Its role in regulating the cardiac response to β-adrenergic stimulation is not yet fully understood. We therefore generated mice deficient in B56α to test the functional cardiac effects in response to catecholamine administration versus corresponding WT mice. We found the decrease in basal PP2A activity in hearts of KO mice was accompanied by a counter-regulatory increase in the expression of B' subunits (β and γ) and higher phosphorylation of sarcoplasmic reticulum Ca²⁺ regulatory and myofilament proteins. The higher phosphorylation levels were associated with enhanced intraventricular press

SUBMITTER: Glaser D 

PROVIDER: S-EPMC9478386 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature