Protein O-linked β-N-acetylglucosamine: A novel effector of cardiomyocyte metabolism and function

► Protein O-GlcNAcylation regulates of cardiomyocyte stress response. ► Increased O-GlcNAc levels linked to both cardioprotection and diabetic complications. ► O-GlcNAcylation is a novel mechanism for regulation of cardiac metabolism. ► Mitochondrial proteins are targets for O-GlcNAcylation. ► New technologies will facilitate characterization of O-GlcNAcylated proteins.