Figure 2

Conservation of alternative splice variants of two OXPHOS genes in D. melanogaster, D. pseudoobscura and A. gambiae. (a,b) Schematic representation and comparison of intron-exon structure of the genes encoding the NADH ubiquinone-oxidoreductase acyl carrier protein and the ATP synthase epsilon chain in D. pseudoobscura (Dp), D. melanogaster (Dm) and A. gambiae (Ag). Coding exons are represented by red boxes and untranslated UTRs by blue boxes. Introns are not drawn to scale. Because no sufficient information is available about the transcribed non coding sequences of D. pseudoobscura, only the coding exons of the D. pseudoobscura genes are shown. mtacp1 exons duplicated in tandem are labelled 'a' and 'b'. (c) alignment of the amino-acid sequences encoded by the duplicate a and b exons of the mtacp1 gene in D. melanogaster (Dm), D. pseudoobscura (Dp), A. gambiae (Ag) and A. mellifera (Am). Residues conserved in both exons are shown in white on a black background. (d) Dendrogram showing the phylogenetic relationships between the duplicated exon DNA sequences used for the alignment shown in (c). The neighbor-joining tree derived from distance matrix analysis was constructed using MultAlin [62]. Other tree-construction methods produced similar results. PAM, percent point accepted mutations.