Fig. 3.

—Distribution of positively selected amino acids in the cysteine protease inhibitor Pit2. The alignment shows the protein sequences of orthologues in Ustilago hordei (UHOR_02064), U. maydis (UMAG_01375), Sporisorium scitamineum (SPSC_03677), S. reilianum f. sp. zeae (sr10529), and S. reilianum f. sp. reilianum (srs_10529). Sites under positive selection detected by a branch-site model are indicated by colored bold letters. Residues colored in red indicate positive selection detected in the respective species and purple residues indicate sites found under positive selection in both species. The yellow shaded area is orthologous to the previously identified conserved PID14 domain, which is required and sufficient for inhibition of a group of papain-like cysteine proteases. Green sequences indicate secretion signal peptides and bold numbers above the alignment indicate positions in UHOR_02064.