Structural and systems characterization of phosphorylation on metabolic enzymes identifies sex-specific metabolic reprogramming in obesity.

Coordination of adaptive metabolism through signaling networks is essential for cellular bioenergetics and homeostasis. Phosphorylation of metabolic enzymes provides a rapid, efficient, and dynamic mechanism to regulate metabolic networks. Our structural analysis stratified phosphosites on metabolic enzymes based on proximity to functional and dimerization domains. Most phosphosites occur on oxidoreductases and are enriched near substrate, cofactor, active sites, or dimer interfaces. Despite low stoichiometry, phosphotyrosine (pY) is overrepresented in functional domains. Using high-fat diet (HFD)-induced obesity in C57BL/6J mice and multiomics, we measured HFD-induced sex-specific dysregulation of pY and metabolites, which was reversible with the antioxidant butylated hydroxyanisole (BHA). Computational modeling revealed predictive pY sites for HFD- or BHA-induced metabolite changes. We characterized functional roles for predictive pY sites on glutathione S-transferase pi 1 (GSTP1), isocitrate dehydrogenase 1 (IDH1), and uridine monophosphate synthase (UMPS) using CRISPR interference (CRISPRi) rescue and stable isotope tracing. Our findings reveal mechanisms whereby cellular signaling fine-tunes enzyme activity and metabolism.