A Chemical Genetic Method for Monitoring Genome-Wide Dynamics of O-GlcNAc Turnover on Chromatin-Associated Proteins

Advances in DNA sequencing are enabling new experimental modalities for studying chromatin. One emerging area is to use high-throughput DNA sequencing to monitor dynamic changes occurring to chromatin. O-Linked N-acetylglucosamine (O-GlcNAc) is a reversible protein modification found on many chromatin-associated proteins. The mechanisms by which O-GlcNAc regulates gene transcription are of high interest. Here we use DNA precipitation methods to enable monitoring time-dependent turnover of O-GlcNAc modified proteins associated with chromatin. Using an antibody-free chemical reporter strategy to map O-GlcNAc to the genome, we performed time course metabolic feeding experiments with wild-type Drosophila larvae alongside larvae lacking O-GlcNAc hydrolase (OGA), which are accordingly unable to remove O-GlcNAc. Analysis of resulting next-generation DNA sequencing data revealed that O-GlcNAc on chromatin-associated proteins at most genomic loci is processed with a half-life in hours. Notably, loss of OGA only in...