Lysine Pyruvylation Mediated by HAT1/p300-SIRT3 Couples Glycolytic Flux to Epigenetic Regulation
Post-translational modifications (PTMs) serve as critical regulatory mechanisms connecting metabolism and protein functions. Following our prior discovery of lysine lactylation (Kla), we herein report the identification and characterization of lysine pyruvylation (Kpy), a previously undescribed PTM driven by the central glycolytic hub metabolite pyruvate. Through integrated biochemical and proteomic strategies, we established the existence and specificity of Kpy. Proteomic profiling revealed Kpy sites across both histones and non-histone proteins, implicating its broad physiological significance. Notably, our investigations demonstrated that Kpy abundance fluctuates in respond to alterations in glycolytic flux and pyruvate concentration, providing a direct mechanism by which metabolic alterations influence protein functions. Additionally, we identified Sirtuin 3 (SIRT3) as the "eraser" enzyme for Kpy removal, while Histone acetyltransferase 1 (HAT1) and p300 (EP300) function as "writer" enzymes responsible for Kpy deposition. Initial mechanistic studies suggested Kpy's regulatory role in transcriptional control. Together, the elucidation of Kpy expands our understanding of metabolite-protein crosstalk through PTMs, providing mechanistic insights into pathophysiological processes and facilitating the development of targeted therapeutic interventions for metabolic disorders. Overall design: CUT&Tag analysis of Kpy modifications in HEK293T cells.