HTT and neuroblastoma: We created neuroblastoma SH‐SY5Y cells which stably express N‐terminal mutant huntingtin and endogenously express TG 2 (SHSY5Y‐htt‐N63‐148‐Q cells; Figure 2A) and examined the effect of AAV‐mediated expression of CaM‐peptide on TG‐activity and mutant huntingtin‐associated neurotoxicity.