The white Gene of Drosophilamelanogaster Encodes a Protein with a Role in Courtship Behavior

Abstract

The white gene of Drosophila melanogaster has been extensively studied, yet it is still not understood how its ectopic overexpression induces male-male courtship. To investigate the cellular basis of this behavior, we examined the sexual behavior of several classes of mutants. We find that male-male courtship is seen not only in flies overexpressing the white gene, but also in mutants expected to have mislocalized White protein. This finding confirms that mislocalizing White transporter in the cells in which it is normally expressed will produce male-male courtship behaviors; the courtship behavior is not an indirect consequence of aberrant physiological changes elsewhere in the body. Male-male courtship is also seen in some mutants with altered monoamine metabolism and deficits in learning and memory, but can be distinguished from that produced by White mislocalization by its reduced intensity and locomotor activity. Double mutants overexpressing white and with mutations in genes for serotonergic neurons suggest that male-male courtship produced by mislocalizing White may not be mediated exclusively by serotonergic neurons. We also find decreased olfactory learning in white mutants and in individuals with mutations in the genes for White's binding partners, brown and scarlet. Finally, in cultured Drosophila and mammalian cells, the White transporter is found in the endosomal compartment. The additional genes identified here as being involved in male-male courtship increase the repertoire of mutations available to study sexual behavior in Drosophila.

Keywords:

• Drosophila melanogaster
• white
• endosome
• courtship
• learning and memory

Acknowledgements

Thanks are due to J.A. Borycz, Dalhousie University, for sharing results in advance of publication, and T. Grigliatti, T. Pfeifer, W. Odenwald, H. Nash, and L.S.B. Goldstein for reagents. The authors thank T. Edwards, W.A. MacDonald, S. Campbell, S. Hanna, and D. Hamilton for their technical advice and assistance and J.A. Gillis, L. McEachern, and D. Kent for their discussion. We also thank the reviewers for helpful comments. This work was supported by the Natural Sciences and Engineering Research Council (NSERC) and Nova Scotia Health Research grants to V.L. and by Regional Partnerships Grant ROP-67480 from the Canadian Institutes for Health Research to I.A.M.

Additional information

Notes on contributors

Matthew Anaka

M.A. and C.D.M. contributed equally to this work