Fig. 3: Ablation of Prohibitin 1 in Schwann cells results in altered mitochondrial morphology.

a Representative electron micrographs highlighting the enlargement of mitochondria in sciatic nerves of Phb1-SCKO animals at postnatal day 20 (P20) (arrows). N = 3 animals per genotype. (b-d) Mitochondria in SCs of PHB1-SCKO mice (red) have a larger perimeter compared to mitochondria of control animals (blue) at P20 (b), P40 (c), and P90 (d). At P40, there is also a population of mitochondria that has a reduced perimeter, suggesting mitochondrial fragmentation. This population is lost at P90, suggesting that the fragmented mitochondria disappear. N = 3 animals per genotype; at least 100 mitochondria from each animal were evaluated. Insets: non-linear regression using a Gaussian curve followed by extra sum-of-squares F test [F(3,42) P20 = 5.482, F(3,38) P40 = 19.48, F(3,34) P90 = 4.813). e Schematic representation of the distribution of mitochondria in a myelinating SC. f–g Confocal z-projections of teased fibers of sciatic nerves of Phb1-SCKO mice and controls illustrating the morphology of Schwann cell mitochondria as labeled by the PhAM reporter (green) near different cellular structures (red). DAPI is indicated in blue. f At P20, there are changes in mitochondrial size. N = 4 animals per genotype. g At P40, some cells lack PhAM expression away from the cell body. N = 3 animals per genotype. h PhAM is not detectable in about 20% of the myelin internodes of Phb1-SCKO animals at P40. N = 4 animals per genotype. Unpaired two-tailed t-test (t = 4.866, df = 6, p = 0.0028). Data are presented as mean ± SEM. **p < 0.01.