Phylogenetic distribution among eukaryotes of core meiotic proteins and their prokaryotic homologs.

Bold columns highlight meiosis-specific proteins, and T. vaginalis is highlighted at the beginning. The names of genera with the most completely annotated genome sequences are highlighted in bold. The presence of orthologs is designated on the basis of phylogenetically verified data (P) obtained by BLASTp searches of public protein sequence databases and by cloning/sequencing (S) of selected genes (from T. vaginalis) in this study or our previous study [1]. The presence (B) of putative homologs identified by BLASTp from recently released sequence data and verified only by bi-directional BLAST searches (Table S1.3 in Supporting Information File S1) are also indicated. If more than one gene is present, copy number follows this designation parenthetically. The absence of meiotic genes from completed genome sequencing projects is indicated by (�C), while empty cells indicate putatively missing data (from unfinished or incompletely annotated genomes). Protein homology was inferred by multiple sequence alignment and Bayesian phylogenetic analyses (see Figure 2 and Figures S1.1�CS1.33 in Supporting Information File S1 for details), except for cells designated by ��B��. Some data excluded from Figures S1.1�CS1.33 in Supporting Information File S1 were phylogenetically verified in equally or similarly rigorous prior studies [1], [50], [101], [102].