Fig. 3. Schistocerca possesses at least two Pax group III genes. (A) Amino acid sequence alignment of Pby1 and Pby2 (Schistocerca americana) with Gsb, Gsbn and Prd (Drosophila melanogaster) reveals conservation in the paired domain, homeodomain and octapeptide (black underline). The extended region of the homeodomain is also shown (gray underline). The addition and deletion of amino acids that result from the alternative splice forms of pby1 and pby2, respectively, are shown above the alignment. Available cDNA sequence for both pby1 and pby2 have been deposited in GenBank (Accession Numbers, AY040535 and AY040536, respectively). (B) Schematic of Schistocerca, Drosophila and vertebrate PgIII gene products. The relative lengths and conserved regions of each gene product are shown. PD, paired domain; HD, extended homeodomain; O, octapeptide. Hatching indicates presumed regions not yet sequenced. Pax3 and Pax7 are from mouse. (C) Phylogenetic analysis of Pby1 and Pby2 amino acid sequences using maximum parsimony. Based on the alignments shown in A, Tree I (partial paired domain alone) is the most parsimonious tree and Tree II (partial paired domain + homeodomain proper) is a strict consensus of the three most parsimonious trees. Both trees support the placement of Pby1 and Pby2 within PgIII. Pax genes that lack full homeodomains were not included in Tree II. Pax groups I, II, III and IV are those originally defined (Balczarek et al., 1997). Pax 1-9 are from mouse; Gsb, Gsbn, Prd, Eyeless, Sparkling and Pox Meso are from Drosophila; and Pax B and Pax D are from the cnidarian Acropora millepora (Miller et al., 2000). Numbers shown reflect the percentage of 1000 bootstrap replicates supporting the indicated node (only values >50% for PgIII nodes are shown, other PgIII nodes are shown in gray).
