Lysine Methylpropionylation, a Hybrid Post-Translational Modification Mediated by p300/PCAF Couples Metabolic Dynamics with Protein Function

Lysine alkylation and acylation serve as crucial links between cellular metabolism and a wide range of biological functions. However, hybrid modifications that combine features of both alkylation and acylation remain largely unexplored. Here, we report the discovery and in-depth characterization of lysine methylpropionylation (Kpm), a hybrid post-translational modification (PTM) defined by the propionylation of monomethyllysine residues. Genome-wide chromatin immunoprecipitation coupled with transcriptomic profiling revealed that Kpm exhibits distinct genomic distribution compared to canonical Kac and Kpr, with preferential enrichment at promoters of genes involved in metabolic pathways. Together, our findings establish Kpm as a dual-feature PTM that integrates metabolic cues with both chromatin regulation and non-histone protein function, offering a mechanistic framework for understanding metabolism-proteome crosstalk. Overall design: ChIP-seq of Kpm, Kac, and Kpr modifications in wild-type and PCCB-knockdown HepG2 cells.