SUMOylation-regulated protein phosphorylation, evidence from quantitative phosphoproteomics analyses.

Protein modification is critical for the regulation of protein functions. Cross-talks among different types of protein modifications should yield concerted and coordinated regulatory networks for physiological functions. Here we have employed system-wide and quantitative phosphoproteomics analyses to reveal a global cross-talk for SUMOylation-modulated phosphorylation. Furthermore, as specific examples, we have shown that the α subunit of casein kinase II is SUMOylated and that this affects the phosphorylation of its substrates. SUMO-regulated phosphorylation is involved in cell cycle control. Our data demonstrate an interplay between protein SUMOylation and phosphorylation and imply a regulatory role for this SUMOylation-modulated phosphorylation.