Genome-wide acceleration of protein evolution in flies (Diptera).
BACKGROUND
The rate of molecular evolution varies widely between proteins, both within and among lineages. To what extent is this variation influenced by genome-wide, lineage-specific effects? To answer this question, we assess the rate variation between insect lineages for a large number of orthologous genes.


RESULTS
When compared to the beetle Tribolium castaneum, we find that the stem lineage of flies and mosquitoes (Diptera) has experienced on average a 3-fold increase in the rate of evolution. Pairwise gene comparisons between Drosophila and Tribolium show a high correlation between evolutionary rates of orthologous proteins.


CONCLUSIONS
Gene specific divergence rates remain roughly constant over long evolutionary times, modulated by genome-wide, lineage-specific effects. Among the insects analysed so far, it appears that the Tribolium genes show the lowest rates of divergence. This has the practical consequence that homology searches for human genes yield significantly better matches in Tribolium than in Drosophila. We therefore suggest that Tribolium is better suited for comparisons between phyla than the widely employed dipterans.
Savard
Joël
J
Institut für Genetik der Universität zu Köln, 50674 Köln, Germany. savard@uni-koeln.de
Tautz
Diethard
D
Lercher
Martin J
MJ
D000818:Animals; D004175:Diptera / Q000235:genetics*; D004330:Drosophila / Q000235:genetics; D019143:Evolution, Molecular; D014644:Genetic Variation; D016678:Genome; D019476:Insect Proteins / Q000235:genetics*; D013995:Time; D014158:Transcription, Genetic; D014231:Tribolium / Q000235:genetics
D019476:Insect Proteins