Fig. 3.

PXR is acetylated at K109) in the hinge. (A) Schematic depicting experimental workflow used to map PXR's acetylation site. (B) Immunoblot confirming the acetylation state of the mock acetylated control and acetylated PXR protein samples that were subjected to LC–MS/MS. (C) Fragment ion spectrum of the acetylated peptide detected in the in vitro acetylated protein sample. (D) Confirmation of K109 acetylation in vivo. HepG2 cells stably expressing the WT or K109R form of FLAG-tagged PXR were treated with or without 10 mM nicotinamide (NAM) and 0.5 µM trichostatin A (TSA) for 2 h. Cells were lysed and lysates were then subjected to FLAG-IP. Eluates were probed for acetylated PXR by Western blot.