Table 1.

List of the PTM sites identified in vivo and in vitro

The source in which the PTM has been identified can be human brain (H), HD mouse model (M), or transfected cell lines (HEK). Phos, phosphorylation; Ac, acetylation.

Huntingtin residue	Modification	Identification source	Reference
Thr3	Phos	HEK	Aiken et al. (8)
Lys6	Ac	HEK	Steffan et al. (12); Thompson et al. (13)
Lys9	Ac	HEK	Steffan et al. (12); Thompson et al. (13)
Ser13/Ser16	Phos	HEK	Thompson et al. (13)
Ser13/Ser16	Phos	M	Ratovitski et al. (22)
Ser116/Ser120	Phos	HEK	Watkin et al. (17)
Ser116/Ser120	Phos	M	Ratovitski et al. (22)
Thr271	Phos	HEK	Watkin et al. (17)
Thr271	Phos	M, H	Ratovitski et al. (22)
Ser421	Phos	HEK	Humbert et al. (18)
Ser421	Phos	H	Ratovitski et al. (22)
Ser432/Ser434	Phos	HEK	Dong et al. (53); Watkin et al. (17)
Ser432/Ser434	Phos	M	Ratovitski et al. (22)
Lys444	Ac	HEK	Jeong et al. (16)
Lys815	Ac	M, H	Ratovitski et al. (22)
Lys818	Ac	M, HEK	Ratovitski et al. (22)
Ser1179	Phos	M, H	Ratovitski et al. (22)
Ser1181	Phos	HEK	Schilling et al. (20)
Ser1181	Phos	M, H	Ratovitski et al. (22)
Lys1190	Ac	M, H, HEK	Ratovitski et al. (22)
Ser1201	Phos	HEK	Schilling et al. (20)
Ser1201	Phos	M	Ratovitski et al. (22)
Lys1204	Ac	M, H, HEK	Ratovitski et al. (22)
Lys1246	Ac	M, HEK	Ratovitski et al. (22)
Ser1864	Phos	M, H, HEK	Ratovitski et al. (22)
Ser1872	Phos	HEK	Huang et al. (54)
Ser1876	Phos	HEK	Huang et al. (54)
Ser1876	Phos	M, H	Ratovitski et al. (22)
Ser2114	Phos	M, HEK	Ratovitski et al. (22)
Ser2116	Phos	M, HEK	Ratovitski et al. (22)
Ser2342	Phos	H, HEK	Ratovitski et al. (22)
Ser2489	Phos	M	Ratovitski et al. (22)
Lys2548	Ac	M, H, HEK	Ratovitski et al. (22)
Lys2615	Ac	HEK	Ratovitski et al. (22)
Ser2652	Phos	HEK	Ratovitski et al. (22)
Ser2653/Ser2657	Phos	HEK	Schilling et al. (20)
Ser2653/Ser2657	Phos	M, H, HEK	Ratovitski et al. (22)
Ser2936	Phos	M, H	Ratovitski et al. (22)
Lys2969	Ac	H, HEK	Ratovitski et al. (22)