Table VI. List of identified UbcH5a/CHIP-catalyzed CYP3A4 ubiquitination sites.
For experimental details, see “Experimental Procedures.” CYP3A4 peptides were derived from Lys-C/tryptic digests. cm, carbamidomethylation; p, phosphorylation.
| No | Site | Peptide sequence | m/z | z | Mass error (ppm) | Score | Expect val |
|---|---|---|---|---|---|---|---|
| 1 | Lys-127 | SAISIAEDEEWK(GlyGly)Ra | 549.939 | 3 | 4.4 | 20.5 | 6.7e-3 |
| 2 | Lys-168 | EAETGK(GlyGly)PVTLK | 643.856 | 2 | 7.5 | 33.6 | 2.3e-6 |
| REAETGK(LeuArgGlyGly)PVTLK | 428.749 | 4 | −3.0 | 25.6 | 1.5e-3 | ||
| 3 | Lys-173 | EAEpTGKPVTLK(LeuArgGlyGly)DVFGAYSMDVITSTSFGVNIDSLNNPQDPFVENpTK | 1380.420 | 4 | 10 | 23.2 | 0.043 |
| EAETGKPVpTLK(LeuArgGlyGly)DVFGAYSMDVITSTSFGVNIDpSLNNPQDPFVENTK | 789.240 | 7 | 8.9 | 16.1 | 0.050 | ||
| 3 | Lys-466 | VLQNFSFK(GlyGly)PC(cm)Ka | 494.592 | 3 | 2.0 | 32.0 | 3.9e-7 |
| 4 | Lys-487 | EpTQIPLKLpSLGGLLQPEK(GG)PVVLKa | 925.506 | 3 | 5.8 | 23.6 | 8.0e-3 |
| LSLGGLLQPEK(GlyGly)PVVLKVESR | 1138.653 | 2 | 15.8 | 15.8 | 1.0e-2 | ||
| 5 | Lys-492 | LSLGGLLQPEKPVVLK(GlyGly)VESRa | 569.830 | 4 | −15.6 | 15.7 | 1.5e-2 |
a Manually annotated spectra provided in the supplemental materials.