A female-biased expressed elongase involved in long-chain hydrocarbon biosynthesis and courtship behavior inDrosophila melanogaster

Abstract

Drosophila melanogaster produces sexually dimorphic cuticular pheromones that are a key component of the courtship behavior leading to copulation. These molecules are hydrocarbons, with lengths of 23 and 25 carbons in males (mainly with one double bond) and 27 and 29 carbons in females (mainly with two double bonds). Here, we describe an elongase gene, eloF, with female-biased expression. The 771-bp ORF encodes a 257-aa protein that shows the highest sequence identity with mouse SSC1 elongase (33%). The activity of the cDNA expressed in yeast was elongation of saturated and unsaturated fatty acids up to C30. RNAi knockdown in Drosophila led to a dramatic modification of female hydrocarbons, with decreased C29 dienes and increased C25 dienes accompanied by a modification of several courtship parameters: an increase in copulation latency and a decrease in both copulation attempts and copulation. Feminization of the hydrocarbon profile in males by using targeted expression of the transformer gene resulted in high expression levels of eloF, suggesting that the gene is under the control of the sex-determination hierarchy. There is no expression of eloF in Drosophila simulans, which synthesize only C23 and C25 hydrocarbons. These results strongly support the hypothesis that eloF is a crucial enzyme for female pheromone biosynthesis and courtship behavior in D. melanogaster.

Insights into the phylogenetic and molecular evolutionary histories of Fad and Elovl gene families in Actiniaria

“…The Elovl1 and Elovl7 clades were sister to each and contain sequences from phylum Chordata. The Elovl1/7‐like clade contains functionally characterized Elovl proteins from the arthropod Aedes aegypti as well as Drosophila melanogaster (Chertemps et al., 2007; Ribeiro et al., 2007). The Novel ElovlB subclade consisted of only protein sequences from phylum Cnidaria and no functionally characterized Elovl proteins.…”

Identification of quantitative trait loci function through analysis of multiple cuticular hydrocarbons differing between Drosophila simulans and Drosophila sechellia females

“…The first cluster containing five genes fell between pros and MtnA, and included eloF, which has female-biased expression in D. melanogaster. Furthermore, eloF affects the relative production of dienes of different chain lengths and is not expressed in D. simulans (Chertemps et al, 2007), thus is an excellent candidate gene. The second cluster of four genes fell between MtnA and slo; one or more of these elongases is likely to be important in the difference between D. simulans and D. sechellia.…”

“…Very little is known about the genes encoding carboxylases, but the elongases and desaturases have received more attention. Recent work has shown that elongase F (eloF), expressed in female D. melanogaster and D. sechellia, but not D. simulans, is involved in the elongation of long hydrocarbons, especially diene pheromones (Chertemps et al, 2007). RNA interference knockdown of eloF in oenocytes is sufficient to reduce the expression of long dienes (Chertemps et al, 2007).…”

Genetics of cuticular hydrocarbon differences between males of the parasitoid wasps Nasonia giraulti and Nasonia vitripennis

“…RNA interference-mediated knock-down experiments revealed yet another female-specific desaturase, encoded by the gene desatF, that is responsible for the introduction of the second double bond in the above 5, 9-and 7,11-alkadienes (Chertemps et al, 2006;Legendre et al, 2008). Finally, Chertemps et al (2007) mapped and identified a gene, eloF, which encodes an elongase that controls the elongation of alkadienes and, to a lesser extent, of alkenes in females of D. melanogaster. These results highlight the progress that has been made in understanding the genetics and biosynthesis of CHCs by research on Drosophila.…”