PIAS1 and Huntington disease: Given that phosphorylation of HTT is responsive to inflammatory cues (Thompson et al., 2009), that PIAS1 is involved in immune function, and that inflammation is increased in HD (Björkqvist et al., 2009; Khoshnan et al., 2004), it is likely that SUMO-2 modification is also responsive to inflammatory cues that appear early in HD.