Figure 1.

ifta-1 (C54G7.4) is an X-box–containing gene that is conserved in ciliated organisms. (A) RFX transcription factor-binding X-boxes are found upstream of ifta-1 in C. elegans, C. briggsae, and H. sapiens. (B) Schematic of the IFTA-1 protein, which consists of 1199 amino acids (in C. elegans) and is predicted to possess three WD protein motifs. (C) Cross-species comparison of the percentage of amino acid identity between IFTA-1 homologues in C. elegans, H. sapiens, Mus musculus, pufferfish, Drosophila melanogaster, C. reinhardtii, Trypanosoma brucei, and Paramecium. Note that IFTA-1 homologues are not present in nonciliated organisms such as A. thaliana and S. cerevisiae.