Evolutionary EST Analysis Identifies Rapidly Evolving Male Reproductive Proteins in Drosophila

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 98; no. 13; pp. 7375 - 7379
• Main Authors: Swanson, Willie J., Clark, Andrew G., Waldrip-Dail, Heidi M., Wolfner, Mariana F., Aquadro, Charles F.
• Format: Journal Article
• Language: English
• Published: United States National Academy of Sciences 19.06.2001; National Acad Sciences; The National Academy of Sciences
• Subjects: Analysis of Variance; Animal reproduction; Animals; Biological Sciences; Complementary DNA; Drosophila; Drosophila - classification; Drosophila - genetics; Drosophila melanogaster; Drosophila melanogaster - genetics; Drosophila simulans; Evolution; Evolution, Molecular; Evolutionary genetics; Expressed Sequence Tags; Genes; Genetic screening; Genitalia, Male - physiology; Genomes; Insect genetics; Insects; Male; Male animals; Males; Maximum likelihood estimation; Molecular Sequence Data; Positive selection; Proteins; Proteins - genetics; Reproductive proteins
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.131568198

Sequence comparisons of genomes or expressed sequence tags (ESTs) from related organisms provide insight into functional conservation and diversification. We compare the sequences of ESTs from the male accessory gland of Drosophila simulans to their orthologs in its close relative Drosophila melanogaster, and demonstrate rapid divergence of many of these reproductive genes. Nineteen (~11%) of 176 independent genes identified in the EST screen contain protein-coding regions with an excess of nonsynonymous over synonymous changes, suggesting that their divergence has been accelerated by positive Darwinian selection. Genes that encode putative accessory gland-specific seminal fluid proteins had a significantly elevated level of nonsynonymous substitution relative to nonaccessory gland-specific genes. With the 57 new accessory gland genes reported here, we predict that ~90% of the male accessory gland genes have been identified. The evolutionary EST approach applied here to identify putative targets of adaptive evolution is readily applicable to other tissues and organisms.