Kinesin 1 localization was altered in TA muscles from nesprin 1α2 KO but not in WT or nesprin 1ΔCH^−/−. (A and B) TA skeletal muscle fibers isolated from WT, nesprin 1ΔCH (A), and nesprin 1α2 KO (B) mice were fixed and stained using an antibody directed to the heavy chain of kinesin 1 (KIF5B) and α-actinin (red). Note that kinesin 1 localized to the NE in both WT and nesprin 1ΔCH (arrowheads) but was diffuse in nesprin 1α2 KO TA muscles (yellow arrows). (C) Western blots of KLC1 and KIF5B from WT and nesprin 1α2 KO TA muscles. Note that the levels of KLC1 were slightly down-regulated, whereas KIF5B levels were unchanged. GAPDH served as a loading control. n = at least three to four pups per genotype for each panel. Bars, 5 µm.