Fig. 7

Overexpression of KCNJ2 enhances structural and metabolic maturation in iPSC-CMs. a Schematic diagram of morphological index analysis. b Representative confocal images of GFP (green) and α-actinin staining (red) in Vector OE and KCNJ2 OE iPSC-CMs. DAPI indicates nuclear staining (blue). Fluorescent detection was assessed with a confocal microscope (Nikon A1). Scale bar, 25 μm. c Bar graphs to compare the cell area, perimeter, circularity and elongation between Vector OE and KCNJ2 OE iPSC-CMs, respectively. Circularity is approximate to 4π × area × perimeter-2. Elongation is reflected with the ratio of major-axis length to minor-axis length. n = 148–203 cells. d The diagram depicts the trace of oxygen consumption rate (OCR) on Vector OE and KCNJ2 OE iPSC-CMs after sequentially administration of 1.5 μM oligomycin (ATP synthase inhibitor), 4 μM FCCP (uncoupler of oxidative phosphorylation in mitochondria) and 1 μM antimycin A (electron transport chain blocker), respectively. e–l Bar graphs to compare a series of fundamental parameters of mitochondrial function between Vector OE and KCNJ2 OE iPSC-CMs, including non-mitochondrial oxygen consumption, maximal respiration, spare respiratory capacity, spare respiratory capacity (%), ATP production, basal respiration, coupling efficiency and proton leak. n = 3 independent differentiations