Rescue of neurite outgrowth in shTDP cells by HDAC6 transfection. Parental SH-SY5Y cells (Ctrl) or cells stably transduced with shRNA against TDP-43 (shTDP) were exposed to RA. After 1d, cells were transfected for 4h with Myc-HDAC6 or control vector. After another 3d RA treatment, cells were fixed and labeled with Alexa568-phalloidin (red) and anti-Myc (green). Nuclei were counterstained with Hoechst (blue). A, shown are representative images. Scale bar corresponds to 20 μm. Quantifications of transfected, Myc-positive cells were performed for the parameters B, number of neurites per cell, C, number of neurite branches and D, mean neurite length. Significance levels are indicated as in Figure 1.