Figure 1.

Refined q-oxPTPome can sensitively monitor H₂O₂-induced classical PTP oxidation. A, Scheme for q-oxPTPome, qPTPome and PTP-SO₃H approaches; see text for details. NEM: N-ethylmaleimide, DTT: dithiothreitol, PV: pervanadate. FASP: filter-aided sample preparation. B-D, Rat1 cells were treated with H₂O₂ at the indicated concentrations for 4 min and then processed for q-oxPTPome. B, Samples were directly analyzed by immunoblotting using oxPTP Ab. C, Samples were immunoprecipitated using oxPTP Ab and immunoblotted for PTP1B (PTPN1). D, Samples were analyzed by mass spectrometry (MS) and quantified by label-free quantification. Data represent mean ± SEM (n=4–8; *p<0.05, **p<0.01, ***p<0.001, ****p<0.0001; ANOVA with Dunnett post-test).