Fig. 1: Mitochondrial cristae dynamics in live cells.

A Representative live-cell time-lapse images of mitochondria in HeLa cells. Mitochondria in HeLa cells were stained with MitoTracker Green (250 nM, 15 min), then were tracked by time-lapse Hessian-SIM (90 frames/sec), 9 raw frames were used to reconstruct one super-resolution image. The indicated images demonstrate the mitochondrial cristae can shorten or extension in a very short period of time. Green, red, and blue arrowheads indicate the dynamic cristae. B Representative live-cell time-lapse images of mitochondrial cristae detached from the inner boundary membrane (IBM) and subsequently shortening. HeLa cells were treated with MitoTracker Green (250 nM, 15 min) and tracked by time-lapse by Hessian-SIM as described in (A). The white arrows marked the continuous shortening of mitochondria cristae, respectively, the red arrows indicate the cristae detached from the mitochondrial IBM then shorten in the mitochondrial matrix. C Representative live-cell time-lapse images of mitochondrial cristae fusing with IBM. HeLa cells were treated with MitoTracker Green (250 nM, 15 min) and tracked by time-lapse Hessian-SIM as described in (A). The green arrowheads showed that the site of mitochondrial cristae fusing with the IBM. D Representative live-cell Hessian-SIM images of mitochondrial cristae fusion event. HeLa cells were treated with MitoTracker Green (250 nM, 15 min) and tracked by time-lapse Hessian-SIM as described in (A). The selected images show that two mitochondrial cristae fused into one crista, the green and red arrows mark the mitochondrial cristae fusion event. E Representative live-cell Hessian-SIM images of mitochondrial crista division event. HeLa cells were stained with MitoTracker Green (250 nM, 15 min) and tracked by time-lapse Hessian-SIM as described in (A). The green and red arrows indicate the mitochondrial crista division process within 3 s. F Representative live-cell time-lapse images of mitochondrial crista–crista contact. HeLa cells were treated with MitoTracker Green (250 nM, 15 min) and tracked by time-lapse Hessian-SIM as described in (A). The green and red arrowheads-indicated mitochondrial cristae contacted each other and then were separated. G, H HeLa cells were stained with MitoTracker Green (250 nM, 15 min) and tracked by time-lapse Hessian-SIM as described in (A). The selected two images (t = 0 s, 0.1 s) (G) or (t = 0 s, 2 s) (H) were merged to show mitochondrial crista dynamic change. The white arrowheads indicate the moved mitochondrial cristae.