The evolution of courtship behaviors through the origination of a new gene in Drosophila.
New genes can originate by the combination of sequences from unrelated genes or their duplicates to form a chimeric structure. These chimeric genes often evolve rapidly, suggesting that they undergo adaptive evolution and may therefore be involved in novel phenotypes. Their functions, however, are rarely known. Here, we describe the phenotypic effects of a chimeric gene, sphinx, that has recently evolved in Drosophila melanogaster. We show that a knockout of this gene leads to increased male-male courtship in D. melanogaster, although it leaves other aspects of mating behavior unchanged. Comparative studies of courtship behavior in other closely related Drosophila species suggest that this mutant phenotype of male-male courtship is the ancestral condition because these related species show much higher levels of male-male courtship than D. melanogaster. D. melanogaster therefore seems to have evolved in its courtship behaviors by the recruitment of a new chimeric gene.
Committee on Genetics, University of Chicago, 920 East 58th Street, Chicago, IL 60637, USA.
Hongzheng
H
Dai
Ying
Y
Chen
Sidi
S
Chen
Qiyan
Q
Mao
David
D
Kennedy
Patrick
P
Landback
Adam
A
Eyre-Walker
Wei
W
Du
Manyuan
M
Long
D000818:Animals; D005075:Biological Evolution; D003380:Courtship; D004331:Drosophila melanogaster / Q000235:genetics* / Q000502:physiology*; D017344:Genes, Insect / Q000502:physiology*; D008297:Male; D009154:Mutation; D010641:Phenotype; D016372:RNA, Antisense / Q000235:genetics; D012726:Sexual Behavior, Animal; D014158:Transcription, Genetic
D016372:RNA, Antisense