Loss of Notum Macrochaetae as an Interspecific Hybrid Anomaly Between Drosophila melanogaster and D. simulans

Corresponding author: Toshiyuki S. Takano, totakano@lab.nig.ac.jp.

Communicating editor: T. F. C. MACKAY

With the aim of revealing genetic variation accumulated among closely related species during the course of evolution, this study focuses on loss of macrochaetae on the notum as one of the developmental anomalies seen in interspecific hybrids between Drosophila melanogaster and its closely related species. Interspecific hybrids between a line of D. melanogaster and D. simulans isofemale lines exhibited a wide range in the number of missing bristles. By contrast, D. mauritiana and D. sechellia lines showed almost no reduction in bristle number in hybrids with D. melanogaster. Genetic analysis showed that the D. simulans X chromosome confers a large effect on hybrid bristle loss, although X-autosome interaction may be involved. This suggests that at least one genetic factor contributing to hybrid anomalies arose recently on a D. simulans X chromosome. Moreover, the results indicate sex dependency: the male hybrids were more susceptible to bristle loss than the female hybrids were. Use of cell type markers suggests that the defect does not lie in cell fate decisions during bristle development, but in the maintenance of neural fate and/or differentiation of the descendants of sensory mother cells.

This article has been cited by other articles:

				D. A. Barbash Nup96-Dependent Hybrid Lethality Occurs in a Subset of Species From the simulans Clade of Drosophila Genetics, May 1, 2007; 176(1): 543 - 552. [Abstract] [Full Text] [PDF]

				T. Takano-Shimizu Genetic Screens for Factors Involved in the Notum Bristle Loss of Interspecific Hybrids Between Drosophila melanogaster and D. simulans Genetics, September 1, 2000; 156(1): 269 - 282. [Abstract] [Full Text]

				D. A. Barbash, J. Roote, and M. Ashburner The Drosophila melanogaster Hybrid male rescue Gene Causes Inviability in Male and Female Species Hybrids Genetics, April 1, 2000; 154(4): 1747 - 1771. [Abstract] [Full Text]

				K. Sawamura, A. W. Davis, and C.-I Wu Genetic analysis of speciation by means of introgression into Drosophila melanogaster PNAS, March 14, 2000; 97(6): 2652 - 2655. [Abstract] [Full Text] [PDF]