Proteomic Analysis of Human Pluripotent Stem Cell-Derived, Fetal and Adult Ventricular Cardiomyocytes Reveals Pathways Crucial for Cardiac Metabolism and Maturation

BACKGROUND: -Differentiation of pluripotent human embryonic stem cells (hESCs) to the cardiac lineage represents a potentially unlimited source of ventricular cardiomyocytes ( V: CMs), but hESC- V: CMs are developmentally immature. Previous attempts to profile hESC- V: CMs primarily relied on transcriptomic approaches, but the global proteome has not been examined. Furthermore, most hESC-CM studies focus on pathways important for cardiac differentiation, rather than regulatory mechanisms for CM maturation. We hypothesized that gene products and pathways crucial for maturation can be identified by comparing the proteomes of hESCs, hESC-derived V: CMs, human fetal (hF) and adult (hA) V: and atrial ( A: ) CMs. METHODS AND RESULTS: -Using 2D-Differential-In-Gel Electrophoresis (DIGE), 121 differentially expressed (>1.5-fold, p