SACS and Autosomal recessive spastic ataxia of Charlevoix-Saguenay: No major defects in microtubules and microfilaments were observed in SACS–/– SH-SY5Y cells differentiated into neurons as well as in Sacs–/– primary PCs (Supplemental Figure 2, D–F), indicating IF remodeling as a primary event in ARSACS pathogenesis.