Exon organisation of the elav -related genes in 11 metazoans. The analyzed species are listed on the left, with classical phylogenetic relationships represented. The number of elav-like genes is listed next to the species names. Percentages of identity between their protein products and the D. melanogaster proteins ELAV, FNE and RBP9 are listed on the right side of the figure. At the top, a typical ELAV-like protein is represented, with its three RRMs and the hinge region between RRM2 and 3. The vertical arrows below point at protein regions that are, depending upon each of the 23 analyzed proteins, either encoded by exon-junctions (Jx, x = 1 to 8, see text) or by an internal exon sequence. The presence of the junction-encoded region is indicated by a vertical bar for each protein.