Moreover, the overexpression of huntingtin can stimulate autophagy and endo-lysosomal systems in neurons [163] and the polyQ expansion in the pathological form of huntingtin can change the phospholipid binding affinity of the huntingtin protein [164] which may explain why huntingtin localizes to endo-lysosomes and autophagosomal structures in neurons from HD patients [163]. Here, HTT is linked to Huntington disease.