FIGURE 2.

Comparative genomic and domain organization of Gnt1 and PgtA from Dictyostelium and Toxoplasma. A and B, exon-intron organization of the gnt1 and pgtA genes. gnt1 (A) and pgtA (B) gene models from Dictyostelium discoideum are from Refs. 8, 9 and available at dictybase.org (27). The gene models from T. gondii (GT1 (type 1) strain) are from Ref. 28. The length from the start codon to the stop codon in nucleotides is in parentheses. C and D, domain organization of Gnt1 (C) and PgtA (D) proteins. Gnt1- and PgtA-like sequences from Toxoplasma and three other coccidian apicomplexans were aligned with corresponding sequences from D. discoideum and three other amoebozoa, and sequences from two chromerid alveolates, as shown in supplemental Figs. S1 and S2. Regions of high conservation among all 10 sequences are shown in color for the glycosyltransferase-like sequences and in gray for non-GT-like sequences. Toxoplasma sequences whose expression has been confirmed at the transcriptional (expressed sequence tags) or proteomic (MS) level are indicated in Ref. 28. Diagrams are shown to scale.