1. Predicted site-specific kinase-substrate relationships in eukaryotes.
2. The total experimental phosphorylation sites were used as input (refer to Additional File 3). 
3. The low threshold was used (refer to our GPS 2.0 article). Both of experimental and predicted PPI information was used. 
4. Five organisms including Saccharomyces cerevisiae, Caenorhabditis elegans, Drosophila melanogaster, Mus musculus and Homo sapiens were considered.
5. Files:
(1) SC.pnc: prediction results for budding yeast
(2) CE.pnc: prediction results for nematode
(3) DM.pnc: prediction results for fruit fly
(4) MM.pnc: prediction results for mouse
(5) HS.pnc: prediction results for human
6. Last updated, Jun. 28, 2010.
