CoPhosK: A method for comprehensive kinase substrate annotation using co-phosphorylation analysis
Fig 2
Distribution of co-phosphorylation among pairs of phosphosites on breast cancer PDX.
The blue histogram shows the distribution of co-phosphorylation (the correlation between the phosphorylation levels) of all pairs of phosphosites in breast cancer PDX (μ = 0.01,σ = 0.22). (a) Illustration of the three different permutations tests that were used to assess the significance of this distribution. The pink histogram in each panel shows the distribution of co-phosphorylation of all pairs of phosphosites in 100 permutation representing (b) randomization of all entries in the phosphorylation matrix (μ = 0.008,σ = 0.20), (c) permutation of all entries across phosphosites for each state (μ = 0.01,σ = 0.20), and (d) permutation of all entries across states within each phosphosite (μ = 0.01,σ = 0.20). The distribution of co-phosphorylation in the original dataset is significantly broader as compared to the distribution of co-phosphorylation in all permutations (Kolmogorov-Smirnov (KS) test p-value << 1E-9).