A molecular study of Abdominal-A in the ant Myrmica rubra reveals lineage dependant evolutionary rates for a developmental gene

We have characterized the abdominal-A locus in a Hymenopteran, the ant Myrm ica rubra. The sequence of the homeotic domain of the Abdominal-A family of orthologous genes is known for a fairly large number of insects but the co mplete sequence of the Abdominal-A protein, is known only for a few. The tw o proteins of Drosophila melanogaster and Tribolium castaneum differ marked ly outside the homeodomain. A comparison of the ant Abdominal-A protein seq uences with those of these two insects shows that the ant and beetle sequen ces are very similar all along the length of the protein. The fruit fly has diverged considerably and equally from the other two insects. This diverge nce reflects different rates of evolution of the protein in different linea ges.