Table 2.
Enzymes responsible for catalyzing PTMs of htt
| Modification | Amino acid | Responsible enzyme |
Altered activity in HD models |
Antagonisti c enzyme, altered in HD? |
|---|---|---|---|---|
| SUMOylation | K6, K9, K15 | Rhes | increased | |
| ubiquitination | K6, K9, K15 | Ubiquitin E3 ligase eg. E2-25K |
reduced | |
| phosphorylati on |
T3 | ? | reduced | |
| S13,S16 | IKK | reduced | ||
| S421 | Akt1, SGK | unresolve d |
PPT1 / PP2A, reduced |
|
| S434 , S1181, S1201 | Cdk5 | reduced | ||
| S2076, S2653, S2657 |
ERK1 | reduced | ||
| acetylation | K444 | CBP | unknown | HDAC1 |
| cleavage | D513 | Caspase-3 | no | |
| D552 | Caspase-2/3 | no | ||
| D586 | Caspase-6 | increased | ||
| T469, S536 | Calpain 1,5,7,10 | increased | ||
| 104-114, 205-214 | Cathepsin D,B,L | increased | ||
| 81-129, R167 | Undefined proteases |
unknown | ||
| G402 | MMP-10 | increased | ||
| palmitoylatio n |
C214 | HIP14 | reduced |