Axon degeneration due to CMT2-associated KIF5A^R280H mutation rescued by a Bclw mimetic peptide. (A) Schematic representation of a Bclw peptide mimetic rescue experiment. A stabilized α-helix of Bcl2 domain of Bclw (called Bclw BH4 SAHB_A; 20 amino acid) was introduced into axons of DRG neurons grown in Campenot cultures. (B) Experimental design of the Bclw mimetic peptide rescue experiment in DRG neurons cultured in compartmented Campenot chambers. (C) Examples of TUJ1 immunostaining; magnified view depicting individual axon morphology; and corresponding binarized images of axons of DRG neurons grown in compartmented cultures expressing control, WT KIF5A, or KIF5A^R280H with either no peptide, Bclw, or Bcl2 peptide. Red boxes outline regions shown for the higher magnification view of axons. Asterisks indicate interruptions in TUJ1 continuity. Scale bar: 100 µm and 10 µm (magnified image). (D) Quantification of axonal degeneration from C, which is calculated by using the ratio of the region of fragmented axons to total axon area (degeneration index [Sasaki et al., 2009]). Control (Ctrl; n = 21 captured images), WT KIF5A (n = 19), KIF5A^R280H with either no peptide (n = 21), Bclw (n = 26), or Bcl2 peptide (n = 25). From three independent experiments; **P = 0.0011; ***P = 0.0010; ****P < 0.0001 by one-way ANOVA; data represent mean ± SEM.