Figure 1

Comparative structure of Runx genes collected from genome sequences of phylogenetically diverse model organisms. Diagram of Runx genes from selected species. Boxes indicate exons and curved lines indicate introns, which are scaled approximately to the scale bar as indicated. Absolute exon and intron sizes are listed in Supplemental Table 2 and Supplemental Figure 1. The Runt domain is represented as filled boxes ranging from light grey (N-terminus) to black (C-terminus) in order to facilitate comparison to the chordate Runt domain, which is encoded by three different exons. The black bar at the end of all the genes represents the VWRPY (or IWRPF in the case of CeRun) Groucho recruitment motif that is at the C-terminus of proteins encoded by all Runx genes, which facilitated mapping of the previously uncharacterised genes. Exon sequences representing 5' and 3' untranslated regions are not depicted in the diagram. For the vertebrate Runx genes, only exons downstream of the proximal promoters (P2) are shown. Human RUNX1 contains 3 additional alternatively spliced exons between those encoding the Runt domain and the C-terminal VWRPY motif [12], which may or may not be present in the mouse orthologue (Mm1) and are not shown here. Because of sequence gaps in the genomic sequence of the Anopheles gambiae RunxA gene (AgA), the exon structure 3' to the Runt domain of this gene is not known, as indicated by question marks. Abbreviations: Mm1, M. musculus Runx1, etc.; Tr1, T. rubripes Runx1, etc.; Ci, C. intestinalis; Sp, S. purpuratus; AgA, A. gambiae RunxA; DmA, D. melanogaster RunxA; DmB, D. melanogaster RunxB; AgL, A. gambiae Lozenge; DmL, D. melanogaster Lozenge; AgR, A. gambiae Runt; DmR, D. melanogaster Runt; Ce, C. elegans.