Figure 5.
Dynamic interplay between of GlcNAcylation and phosphorylation. A. O-GlcNAc and O-phosphate can compete for the same site. This competition can change the activity or stability of the proteins (e.g. c-Myc; Thr 58). B. In some cases, O-GlcNAc and O-phostate modification occurs within ∼10 amino acids range, regulating the function of the protein substrates (e.g. CTD repeat; Ser 2 and 5 for O-phosphate, Thr 4 for O-GlcNAc). C. GlcNAcylation and phosphorylation can occur on the same protein at proximal sites. The balance between GlcNAcylation and phosphorylation can change the cellular function of the protein (e.g. Akt; Thr 308 and Ser 473 for O-phosphate, Ser 473 for O-GlcNAc).