SCD-containing proteins in S. cerevisiae. (A) List of eleven reported SCD domains . For each protein, the number of S/T-Q sites within the SCD(s) is indicated with the amino acid positions in brackets. Graphical representations of the approximate location of the SCD along the length of the protein are shown on the right with reported phosphorylation sites from UniProt. For references, see Additional file 1: Table S1 (B) Distribution of the lengths of SCD-containing proteins as compared to a log-normal distribution (p-value = 0.2855). The length of protein (x-axis) is plotted against the frequency of occurrence in either the census (black) or the yeast proteome (red). (C) A pie chart showing the proportions of SCD proteins in the census that are known or novel, apportioned by whether pS/T-Q sites are characterized within the SCD. (D) Alignment of amino acids flanking known phosphorylated S/T-Q motifs in yeast, with S/T being position 0. Each unique amino acid is given a color, with the size of letter indicating the proportion of motifs having that amino acid at the position indicated. Evidence of phosphorylation was obtained from UniProt for both reported SCDs of Tel1/Mec1 targets (left) and for all known and putative SCD domains in the census (right).