Fig. 5.

Time course of phosphorylation changes at Ser-293, Ser-300, and Ser-232 in PDHE1α following kinase inhibition with DCA. A, relative quantitation over three injection replicates for diphosphopeptide, YHGHpS²⁹³MSDPGVpS³⁰⁰YR, with precursor ion M extracted at m/z 876.8155. B, relative quantitation for the corresponding phosphopeptides, YHGHpS²⁹³MSDPGVSYR and/or YHGHSMSDPGVpS³⁰⁰YR, with precursor ion M extracted at m/z 836.8323. C, phosphopeptide YGMGTpS²³²VER with precursor ion M extracted at m/z 540.2150. D, independent Western blot analysis of PDHE1α phosphorylation with phosphosite-specific and total protein antibodies in response to DCA treatment.