Chemoproteomic profiling of progesterone-interacting proteins in living cells

Progesterone (Prog) regulates diverse cellular processes through interactions with protein targets, yet its global interaction landscape remains incompletely defined. Chemoproteomic profiling using a photoaffinity probe identified 159 interacting proteins in living cells. Ceramide synthase 2 (CERS2) was characterized as a progesterone-binding candidate, and its knockdown partially attenuated the Prog-induced inhibition of HeLa cell proliferation.