Scansite

Scansite searches for motifs within proteins that are likely to be phosphorylated by specific protein kinases or bind to domains such as SH2 domains, 14-3-3 domains or PDZ domains. Optimal phosphorylation sites for particular protein Ser/Thr kinases or protein-Tyr kinases are predicted using the matrix of selectivity values for amino acids at each position relative to the phosphorylation site as determined from the oriented peptide library technique described by Songyang et al., 1994, Current Biology 4, 973-982 and Songyang et al., 1995, Nature 373, 536-539. The same matrices of selectivity values are used in an approach to provide relative scores of candidate motifs in protein sequences evaluated. The Motifscanner program utilizes an entropy approach that assesses the probability of a site matching the motif using the selectivity values and sums the logs of the probability values for each amino acid in the candidate sequence.