Divergence of Larval Morphology between Drosophila sechellia and Its Sibling Species Caused by Cis-Regulatory Evolution of Ovo/Shaven-Baby

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 97; no. 9; pp. 4530 - 4534
• Main Authors: Sucena, Elio, Stern, David L.
• Format: Journal Article
• Language: English
• Published: United States National Academy of Sciences of the United States of America 25.04.2000; National Acad Sciences; National Academy of Sciences; The National Academy of Sciences
• Series: Special Feature
• Subjects: Animals; Biological Evolution; Biological Sciences; Body Patterning; Crosses, Genetic; DNA-Binding Proteins - genetics; Drosophila; Drosophila - anatomy & histology; Drosophila - genetics; Drosophila - growth & development; Drosophila melanogaster - genetics; Drosophila Proteins; Drosophila sechellia; Evolution; Evolution, Molecular; Female; Female animals; Genes, Insect; Genetic Complementation Test; Genetic loci; Genetic mutation; Genetics; Hair; Insect larvae; Larva; Male; Male animals; Mutation; ovo/shaven-baby gene; Phenotypes; Phylogeny; Sex chromosomes; Species Specificity; Transcription Factors - genetics; X Chromosome; Zoology
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.97.9.4530

We report an extreme morphological difference between Drosophila sechellia and related species of the pattern of hairs on first-instar larvae. On the dorsum of most species, the posterior region of the anterior compartment of most segments is covered by a carpet of fine hairs. In D. sechellia, these hairs have been lost and replaced with naked cuticle. Genetic mapping experiments and interspecific complementation tests indicate that this difference is caused, in its entirety, by evolution at the ovo/shaven-baby locus. The pattern of expression of the ovo/shaven-baby transcript is correlated with this morphological change. The altered dorsal cuticle pattern is probably caused by evolution of the cis-regulatory region of ovo/shaven-baby in the D. sechellia lineage.