Table 2.
Phosphorylated peptides quantified
| Measured peptide | Extended-peptide standarda | Phosphate locations | Extended peptide sequenceb |
|---|---|---|---|
| 175-190-p1 | 170-195-p181 | T181 | RIPAKTPPAPK[T]PPSSGEPP(K)SGDRS |
| 195-209-p1c | 190-214-p202 | S202 | KSGDRSGYSSPG[S]PGTPGS(R)SRTPS |
| 190-214-p205 | T205 | KSGDRSGYSSPGSPG[T]PGS(R)SRTPS | |
| 195-209-p2 | 190-214-p202 + 205 | S202 + T205 | KSGDRSGYSSPG[S]PG[T]PGS(R)SRTPS |
| 210-224-p1 | 205-229-p217 | T217 | TPGSRSRTPSLP[T]PPTREP(K)KVAVV |
| 210-224-p2 | 205-229-p212 + 217 | T212 + T217 | TPGSRSR[T]PSLP[T]PPTREP(K)KVAVV |
| 210-224-p3d | Same as for 210-224-p2 | ||
| 212-224-p1e | 205-229-p217 | T217 | TPGSRSRTPSLP[T]PPTREP(K)KVAVV |
| 225-240-p1 | 220-245-p231 | T231 | TREPKKVAVVR[T]PPKSPSSA(K)SRLQT |
| 225-240-p2c | 220-245-p231 + 235 | T231 + S235 | TREPKKVAVVR[T]PPK[S]PSSA(K)SRLQT |
| 220-245-p231 + 237 | T231 + S237 | TREPKKVAVVR[T]PPKSP[S]SA(K)SRLQT | |
| 220-245-p231 + 238 | T231 + S238 | TREPKKVAVVR[T]PPKSPS[S]A(K)SRLQT | |
| 225-240-p3c | 220-245-p231 + 235 + 237 | T231 + S235 + S237 | TREPKKVAVVR[T]PPK[S]P[S]SA(K)SRLQT |
| 220-245-p231 + 235 + 238 | T231 + S235 + S238 | TREPKKVAVVR[T]PPK[S]PS[S]A(K)SRLQT | |
| 220-245-p231 + 237 + 238 | T231 + S237 + S238 | TREPKKVAVVR[T]PPKSP[S][S]A(K)SRLQT | |
| 386-406-p1c | 379-411-p396 | S396 | RENAKAKTDHGAEIVYK[S]PVVSGDTSP(R)HLSNV |
| 379-411-p404 | S404 | RENAKAKTDHGAEIVYKSPVVSGDT[S]P(R)HLSNV | |
| 386-406-p2 | 379-411-p396 + 404 | S396 + S404 | RENAKAKTDHGAEIVYK[S]PVVSGDT[S]P(R)HLSNV |
| 386-406-p3 | Same as for 396-406-p2 | ||
| 407-438-p1d | [U-15N]-labelled non-phosphorylated 407–438 | …HLSNVSSTGSIDMVDSPQLATLADEVSASLAK…[U-15N] | |
| 407-438-p2d | |||
| 407-438-p3d | |||
a Numbering according to tau 2N4R
b [X] amino acid with phosphate group, (X) isotope labelled amino acid; [13C6,15N2-Lys] or [13C6,15N4-Arg]; black letters are expected peptide after trypsination (based on experiments) and red letters are extended sequence parts
c Labelled standards had the same retention time and since quantification was performed with the intact peptide no distinction was made for different phosphate locations, just the number of phosphate groups
d For these peptides no specific standards were obtained so in these cases surrogate standards were used
e Depending on phosphate location different tryptic peptides were produced, cf. 210-224-p1