A global quantitative screen for phosphorylation changes that occur within the first minutes after addition of DIF-1 (differentiation inducing factor) to Dictyostelium cells, using a triple-label SILAC approach. Ax2 cells were labelled in light, medium and heavy medium then starved (5 hr) before DIF treatment. Cells were harvested at 1,5,8,15 minute post treatment to allow time-course of stimulation to be constructed from 2 overlapping triplex experimental samples A(0,1,8 min) amd B(0,5,15) with each experiment repeated in biological triplicate.