1Université Paris-Sud, UMR 8620, NAMC, Bât. 446, 91405 Orsay Cedex, France.
2Department of Entomology, New York State Agricultural Experiment Station, Cornell University, Geneva, NY 14456, USA.
There is a marked geographical polymorphism among D. melanogaster populations with respect to the female dienes: non African females like Canton S (CS) have 7,11 heptacosadiene (7,11 HD) in abundance (~500ng per female), while African females like Tai have much less of this sex pheromone, together with a large amount of its position isomer 5,9 heptacosadiene (5,9 HD). The involvement of a desaturase with different substrate specificity in Tai and CS, resulting in the production of 5 and 7 compounds has been hypothesised. Genetic analysis has shown that this pheromone difference is due to a segregating factor localised to a single locus, 87C-D1, which also contains the locus of a desaturase gene2. We have therefore cloned the desaturase open reading frame (ORF) in the Tai strain to compare functional expression of desaturases from both strains, when expressed in yeast. Results are presented and discussed.
1. Coyne, J.A., Wicker-Thomas, C. and Jallon, J. M. (1999) Genet. Res. 73, 189-203.
2. Wicker-Thomas, C., Henriet, C. and Dallerac, R. (1997). Insect Biochem. Molec. Biol. 27, 963-972.