Figure 4.

Enzyme phosphorylation across the cell cycle correlates with maximum flux

(A) Pro-B cells were synchronized by growing in media without IL-3 for 36 h and then released from G0 by regrowingthem in the presence of IL-3. Phosphoproteomics data were collected at each phase. In addition, metabolomics data from the same system from Lee et al. was used to build metabolic models for each phase.

(B) All proteins that show at least two-fold change in phosphorylation are shown. For those proteins associated with multiple reactions, the reaction with the highest flux change is shown. Markers are colored by cell cycle phase (red G0/G1, blue G1, green G1/S, and violet G2/M). Among the proteins that showed at least 5-fold difference in phosphorylation between phases, the average correlation was 0.56 between the normalized maximum flux and fold change in phosphorylation. The correlation increases to 0.9 for proteins that show a tenfold difference and is 0.17 for proteins that show 2-fold difference.