(A) Sequence conservation of Tra1. 18 Homologs of Tra1 from 17 species (S. cerevisiae, S. pombe Tra1, S. pombe Tra2, K. lactis, C. albicans, C. glabrata, C. thermophilum, D. melanogaster, C. elegans, A. thaliana, O. sativa, N. crassa, A. niger, H. sapiens, X. tropicalis, D. rerio, M. musculus and G. gallus) were aligned with Clustal Omega (Sievers et al., 2011) and submitted to the CONSURF server (Ashkenazy et al., 2010) for conservation scoring. Scores are plotted as a function of S. cerevisiae Tra1 residue position. Grey trace indicates scores for individual residues, red trace indicates scores averaged over an 11-residue sliding window. The domain structure of Tra1 is indicated above the trace, as drawn for Figure 1D. The highlighted region shaded in orange is expanded in the next panel. (B) Example of sequence alignment of Tra1 over the residues shaded in previous panel with UNIPROT codes for each sequence. Numbering is for S. cerevisiae Tra1.