Table 1. Tau phosphorylation sites identified in sod2 null mouse brain tissue.
| residues | Detected by Antibody | % change a | mass spec ID b | phospho peptide observed by mass spectrometry | P site ID |
| Thr-205 | Yes | 728 | +/− | c | MS c |
| Ser-404 | Yes | 309 | +/− | S396PVVSGDTpS404PR406 | MS/MS d |
| Ser-396 | Yes | 210 | +/− | T386DHGAEIVYKpS396PVVSGDTpS404PR406 | MS e |
| Ser-214 | Yes | 63 | + | T212PpS214LPTPPTREPK224 | MS/MS |
| Thr-231 | Yes | 147 | + | V226AVVRpT231PPKSPSASK240 | MS/MS |
| Ser-202 | Yes | NS | + | S195GYSSPGpS202PGTPGSR209 | MS/MS |
| Thr-181 | No | − | + | T175TPSPKpT181PPGSGEPPK190 | MS/MS f |
| Ser-159 | ND | − | + | G156AApS159PAQKGTSNATRIPAK174 | MS/MS |
a: Percent changes of listed residue in sod2 null mice relative to sod2wild-types (normalized to 100%, see Figure 1), both treated with EUK189 at 1 mg/kg quantitated by Western blotting with monoclonal antibodies for the indicated tau residues, NS– not significant, ND – not done.
b: identifications were positive (+) if a MS/MS spectrum could be unambiguously interpreted to identify a unique phosphorylation site. In three cases (+/−) assignments were based on MS or MS/MS data and alternative sites were possible.
c: several matching phospho peptides observed by ESI-MS (i.e., peptides: mono-/di-phosph. S195-R209 and mono-/di-phosph. S181-R209);
d: Phosphorylate site possibly on Ser-404, Thr-403 or Ser-400;
e: peptide observed with 1P and 2P groups;
f: differences in peptide sequence (human vs. mouse) likely accounting for negative antibody result (homologous human peptide: TPPAPKTPPSSGEPPK);
g: no antibody available for Ser-159.