Table 3.
Unique fragment ions used to quantify phosphorylation sites
| Start | Stop | Peptide sequence | Phosphorylation site | Product ion (m/z)* | Mass (Da) |
|---|---|---|---|---|---|
| 28 |
38 |
GpSLTEQEPAER |
Ser29 |
y8 (+1) |
959.40 |
| |
|
|
|
y9 (+1) |
1072.50 |
| 501 |
511 |
KLNpSTSDIEEK |
Ser504 |
b4 (+1) |
523.23 |
| |
|
|
|
y7 (+1) |
821.39 |
| 645 |
659 |
pSpTQGVTLTDLQEAER |
Ser645/Thr646 |
b2 (+1) |
269.05 |
| |
|
|
|
b3 (+1) |
397.11 |
| |
|
|
|
b4 (+1) |
454.13 |
| |
|
|
|
b5 (+1) |
553.20 |
| |
|
|
|
y10 (+1) |
1175.59 |
| |
|
|
|
y11 (+1) |
1274.66 |
| |
|
|
|
y12 (+1) |
1331.68 |
| |
|
|
|
y13 (+1) |
1459.74 |
| 711 |
720 |
pSLDEEPICHR |
Ser711 |
y6 (+1) |
754.37 |
| |
|
|
|
y7 (+1) |
883.41 |
| |
|
|
|
y8 (+1) |
998.44 |
| 755 |
773 |
FSVPDpSESSETTTNTTTAK |
Ser760† |
b7 (+1) |
842.30 |
| |
|
|
|
y12 (+1) |
1241.59 |
| |
|
|
|
y13 (+1) |
1370.63 |
| 837 |
853 |
LEpSGGSNPTTSDSYGDR |
Ser839 |
b3 (+1) |
410.10 |
| |
|
|
|
y12 (+1) |
1299.50 |
| |
|
|
|
y13 (+1) |
1356.60 |
| y14 (+1) | 1413.60 |
*m/z, mass-to-charge ratio.
† Since Scaffold PTM analysis indicated that only Ser760 or Ser762 is phosphorylated on this peptide, unique fragment ion selection was based on the comparison between pSer760 and pSer762.