Comparison of the structure of the GMC cluster in D. melanogaster , A. gambiae , A. mellifera , T. castaneum. The GMC cluster is located within the Flo-2 gene in opposite transcriptional orientation in all species. The coding regions of Flo-2, adjacent to the cluster, are shown in solid black. The transcriptional orientation of each GMC gene is shown by an open arrow that also shows the position of each gene. Only for A. gambiae GMCβ4, the gene structure is shown to indicate alternative splicing (also see Figure 5). The other genes may or may not contain introns. The highly conserved gene subfamilies, GMCα, δ, ε, ζ, and θ are indicated by dotted lines. Positions of non-GMC genes present in D. melanogaster and T. castaneum are indicated by vertical arrows. The sequences of these non-GMC genes are not homologous to each other. Figures are not drawn to scale.