Figure 1.

Venn diagrams showing exceptionally high prevalence of tyrosine phosphorylation in O-GlcNAc modified proteins. (A) Serine, threonine and tyrosine phosphorylation status of all known O-GlcNAc modified proteins curated at PhosphoSitePlus^® http://www.phosphosite.org webcite (B) Phosphorylation (i.e. pS/pT/pY) and tyrosine phosphorylation status of dynamically altered O-GlcNAc modified (a total of 29 proteins) in response to inhibition of glycogen synthase kinase-3 (GSK-3). gS, GlcNAcylated serine; gT, GlcNAcylated threonine; pS, phosphorylated serine; pT, phosphorylated threonine; pY, phosphorylated tyrosine; PNR, phosphorylation not reported yet.