Fig. 4: Mitochondria are significantly fragmented in axons of fl/fl E18 DRG sensory neurons of the CMT2B mutant mice.

E18 DRG sensory neurons from + /+, fl/+, fl/fl embryos were dissected, cultured on PLL-coated cover-glasses and maintained as described in Materials and Methods. At DIV4-7, neurons were treated with Mito Tracker and time-lapsed images were captured with live imaging microscope. a: representative images of axonal mitochondria from + /+, fl/+, fl/fl; b: Aspect ratio for each group was measured as in Figs. 1–3. The numbers of mitochondria in b were analyzed are: n = 73 for + /+, n = 87 for fl/+, n = 91 for fl/fl. In c, representative images of mitochondria in axons of DRG neurons from vehicle-treated + /+, DMSO-treated fl/+ or fl/+ treated with 50 µM, 100 µM, 200 µM Mdivi-1, fl/fl treated with DMSO or 100 µM Mdivi-1. Quantitative measurements of aspect ratio under these conditions are presented in d. The numbers of mitochondria in d were analyzed are: n = 257 from 19 axons for+ /+, n = 249 from 14 axons for fl/+ with vehicle treatment, n = 262 from 15 axons for fl/+ with Mdivi-1 50 µM treatment, n = 152 from 13 axons for fl/+ with Mdivi-1 100 µM treatment, n = 235 from 18 axons for fl/+ with Mdivi-1 200 µM treatment, n = 174 from 12 axons for fl/fl with vehicle treatment, n = 220 from 9 axons for fl/fl with Mdivi-1 µM treatment. Results are shown as mean ± SEM. Significance analysis was carried out using Prism. Statistical significances were calculated by One-Way ANOVA or unpaired t-test. All p values are shown in the graphs.