mfn2Scr (black) and mfn2Si (white) MSCs were exposed to osteogenesis media for 48 h (commitment time). Real time whole-cell respiration traces were obtained (A). Basal oxygen consumption rates (B), ATP-production dependent OCR (C), Maximal (D), Spare respiratory capacity (E), H+ Leak-linked OCR (F) and Non-mitochondrial respiration (G) were obtained from traces such as those in Panel A. Extracellular acidification rates (ECAR) (H) were measured by extracellular flux analysis as described in the Methods section. * p ≤ 0.05, ** p ≤ 0.001, ns = not significant.