Because autophagy inducers have been shown to be protective in various animal models of HD and neurodegenerative disorders (Rubinsztein et al., 2007; Sarkar et al., 2009b), we tested the efficacy of L-NAME in a Drosophila model of HD. Flies expressing a mutant huntingtin fragment with 120 glutamines (Q120) in their photoreceptors exhibit retinal degeneration, a phenomenon that is not observed in flies expressing the wild-type protein with 23 glutamines (Q23) (Jackson et al., 1998). Here, HTT is linked to Huntington disease.