O‐GlcNAcylation of the Human Kinome

Abstract

O‐GlcNAc, first characterized more than 30 years ago, is an O‐linked β‐N‐acetylglucosamine moiety attached to the side chain hydroxyl of a serine or threonine residue. O‐GlcNAc has been found on over 4,000 cytoplasmic and nuclear proteins. The addition of O‐GlcNAc to proteins is catalyzed by O‐GlcNAc transferase (OGT) while its removal is catalyzed by O‐linked N‐acetyl‐β‐D‐glucosaminidase (OGA). This dynamic and reversible modification is emerging as a key regulator of various cellular processes, such as signal transduction, transcription, cell cycle progression and protein‐protein interactions. O‐GlcNAc plays important roles in human diseases, such as cancer, diabetes and neurological disorders. Protein phosphorylation is a post‐translational modification that serves as a rapid and reversible means to modulate protein activity and transduce signals, the regulation of phosphorylation is a central mechanism in cell health and disease. The addition and removal of phosphorylation is through kinases and phosphates respectively, but little is known about O‐GlcNAcylation of kinases.Kinase microarray which has 370 kinases printed in identical pair spots indicated that 297 kinases are substrates for OGT. In addition, 10 kinases were picked from kinase array for overexpression and immunopreciptation to map O‐GlcNAc site. To further confirm the results in vivo, home‐made kinase inhibitor beads were used to pull down the kinases in rat brain. 223 kinases were identified by mass spectrometry and more than 20 kinases have been identified as O‐GlcNAcylated proteins.Support or Funding InformationSupported by NIH P01HL107153, R01DK61671 and R01GM116891. Dr. Hart receives a share of royalty received by the university on sales of the CTD 110.6 antibody, which are managed by JHUThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.