Figure 1.

Stylized depiction of the matching between post-translational modification sites and amino acid substitutions. In this example, an 11-residue fragment corresponding to an experimentally verified phosphorylation site (serine, colored in red) from M. musculus is first matched to a homologous protein from H. sapiens. The corresponding residue S15 in the human protein is subsequently designated as phosphorylated (homology site). Finally, an observed amino acid substitution E17D, located within 3 residues from S15, is considered to impact the phosphorylation site (neighborhood match).