Figure 4

Evolutionary features of cystatins in T. urticae . (A) Phylogram of T. urticae cystatin sequences showing the presence of functional conserved residues in the four cystatin groups deduced from the phylogenetic tree. Amino acid sequences responsible of the inhibitor-C1A enzyme interaction are shaded in green. Putative sequences involved in C13 legumain inhibition are coloured in purple. Cysteine residues involved in disulphide bridges are in blue. (B) Homology models of T. urticae cystatins created using SWISS-MODEL. The residues in the region that interacts with C1A peptidases are coloured in green. The residues that could be involved in legumain inhibition are coloured in purple. Cysteines are coloured in blue. Red, α-helix; yellow, β-sheets.