Fig. 6

Differential conservation of orthologous and homeologous Xenopus ceacam and flanking genes. Nucleotide sequences of N exons and the open reading frames from ceacam and flanking genes, respectively, from X. tropicalis were compared codon-wise with each of the two homeologous orthologs of X. laevis (a) or the X. laevis homeologs with each other (b) after manual removal of gaps and the ratio of the rate of nonsynonymous and synonymous mutations was calculated. The resulting dN/dS values were plotted using the X. tropicalis gene order on chromosome 7 (a) or the X. laevis gene order on chromosome 7S (b). In cases of recent gene duplication of one of the orthologs in X. tropicalis or X. laevis dN/dS ratios for all orthologous pairs were calculated and plotted as mean and deviation or standard deviation. The type of signaling motif present in the corresponding proteins can be inferred from the schematic representation of the protein domains below the graphs (see Fig. 4 for keys to domains and motifs). Chr, chromosome