Methylglyoxal-derived post-translational arginine modifications are abundant histone marks

Histone post-translational modifications (PTMs) regulate chromatin dynamics, DNA accessibility, and transcription to expand the genetic code. Many of these PTMs are produced through cellular metabolism to offer both feedback and feedforward regulation. Here, we describe the existence of Lys and Arg modifications on histones by the glycolytic by-product, methylglyoxal (MGO). Our data demonstrate that adduction of histones by MGO is an abundant modification, present at the same order of magnitude as Arg methylation. These modifications were detected on all four core histones at critical residues involved in both nucleosome stability and reader domain binding. In addition, MGO treatment of cells lacking the major detoxifying enzyme, glyoxalase 1, results in a marked disruption in H2B acetylation and ubiquitylation, without affecting H2A, H3, and H4 modifications. Using RNA-Seq, we show that MGO is capable of altering gene transcription, most notably in cells lacking GLO1. Lastly, we show that the deglycase, DJ-1, protects histones from adduction by MGO. Collectively, we demonstrate the existence of a previously undetected histone modification derived from glycolysis, which may have far reaching implications on the control of gene expression and protein transcription linked to metabolism.