Extended Data Fig. 4: LIPTER deficiency compromises mitochondrial function and induces apoptosis of human iPSC-CMs.
From: Lipid droplet-associated lncRNA LIPTER preserves cardiac lipid metabolism
a, Comparing the expression levels of CD36, TG synthesis/lipolysis related genes and PLIN5 in enriched WT and LIPTERKO hiPSC-CMs at day 40 of differentiation using RT-qPCR. Bars represent mean values ± s.e.m. Unpaired two-tailed t-test is used for comparison. ****p < 0.0001, **p < 0.01. ns. no significance. (n = 4 independent experiments). b, Western blotting detection of GPAM, PLIN5 and ATGL1 protein expressions in enriched WT and LIPTERKO hiPSC-CMs at day 40 of differentiation. c, Statistical analysis of Western blotting results in b. Bars represent mean values ± s.e.m. Unpaired two-tailed t-test is used for comparison. **p < 0.01, *p < 0.05. (n = 3 times of independent experiments in the 1st and 3rd groups; n = 4 independent experiments in the 2nd group). d, WT and LIPTERKO hiPSC-derived embryoid bodies were treated with 200 µM palmitic acid for 4 days, followed by immunostaining for PLIN5 and Neil Red lipid staining on EB sections. Arrows indicate condensed PLIN5. The experiment was carried out 3 times with similar outcomes. e, Live cell images showing the fusion of Rhodamine B-palmitic acid (red) labeled-LDs with mitochondria (green) and subsequent diminishment in WT hiPSC-CMs over 45 min, while no apparent LD-mitochondria fusion was observed in LIPTERKO, and MYH10KO hiPSC-CMs. Images were from the continuous live cell imaging during 45 min of cultured hiPSC-CMs. The experiment was carried out 3 times with similar outcomes with statistical results in (f). f, Quantification of the ratios of LD fused with mitochondria in e. Bars represent mean values ± s.e.m. Unpaired two-tailed t-test is used for comparison. *p < 0.05. (n = 3 independent experiments). g, Analyses of the maximal oxygen consumption values with Palmitate:BSA between conditions without and with Etomoxir (Eto) to compare relative fatty acid oxidation (FAO) capabilities (yellow zone) in WT, LIPTER KO and LIPTER KO/OE hiPSC-CMs. The experiment was carried out 4 times with similar outcomes. h, Representative immunofluorescent images of TUNEL and cTnT co-staining on day 40 hiPSC-EB sections. The experiment was carried out 5 times with similar outcomes. i, Representative immunofluorescent images of Cleaved Caspase-3 and cTnT co-staining on day 40 hiPSC-EB sections. The experiment was carried out 4 times with similar outcomes. Source numerical data and unprocessed blots are available in source data.
