Figure 2

Multiple sequence alignment of the Runt domain from collected sequences. Alignment of Runx amino acid sequences created using Clustal W [16]. The number 1 denotes the conventional beginning of the Runt domain, which is 128 amino acids long. The shading highlights areas of amino acid conservation, with yellow indicating absolute conservation among all members, and blue or green indicating high conservation of a residue among several members. The domain structure (alpha helix and beta sheet elements) determined for MmRunx1 [14, 17], is shown as arrows above the alignment, and the surfaces involved in DNA contact (major and minor groove, shown in green) or interaction with specific structural motifs within the beta subunit (shown in pink) are denoted by lines above the structural motifs [14]. In cases where it is known, amino acid pairs split by introns in the primary transcripts are underlined and in boldface (i.e., all but the two spider sequences, the crayfish, and the nematode Meloidogyne hapla, for which only cDNAs are available). The arrow indicates a highly conserved intron that falls within sequence that encodes the purine nucleotide-binding consensus. Note that the Runt domains from the spider gene Cs2 and the nematode gene Mh are partial, as indicated by the x's; these partial sequences were not used in the alignment used to generate trees (Table 1 and Figure 3). Abbreviations are as in Figure 1, with the addition of Pl, Pacifastacus leniusculus; Cs1, Cupiennius salei Run-1, etc.; Mh, Meloidogyne hapla.