Labeur C, Dallerac R, Wicker-Thomas C. Involvement of desat1 gene in the control of Drosophilamelanogaster pheromone biosynthesis. Genetica 114: 269-274

Université Paris-Sud, UMR8620, NAMC, Orsay, France.
Genetica (Impact Factor: 1.4). 05/2002; 114(3):269-74. DOI: 10.1023/A:1016223000650
Source: PubMed


Cuticular pheromones in Drosophila melanogaster are unsaturated hydrocarbons with at least one double bond in position 7: 7-tricosene and 7-pentacosene in males and 7,11 -heptacosadiene and 7,11 -nonacosadiene in females. We have previously shown that a desaturase gene, desat1, located in chromosome region 87 C could be involved in this process: the Desat1 enzyme preferentially leads to the synthesis of palmitoleic acid, a precursor of omega7 fatty acids and 7-unsaturated hydrocarbons. Therefore, we have searched for P-elements in the 87 region and mapped them. One was found inserted into the first intron of the desat1 gene. Flies heterozygous for this insertion showed a large decrease in the level of 7-unsaturated hydrocarbons, comparable to that observed in flies heterozygous for a deficiency overlapping desat1. Less than 1 % of flies homozygous for this insertion were viable. They were characterized by dramatic pheromone decreases. After excision of the transposon, the pheromone phenotype was reversed in 69% of the lines and the other excision lines had more or less decreased amounts of 7-unsaturated hydrocarbons. All these results implicate desat1 in the synthesis of Drosophila pheromones.

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Available from: Claude Wicker-Thomas, Feb 06, 2015
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    • "These cases of genes originating from recent lineage-specific expansions with differential intraspecific expression patterns are suggestive of gene duplication followed by neofunctionalization (Ohno 1970). Another noteworthy observation regarding First Desaturase gene expression in ants is that these genes do not seem to fulfill metabolically essential roles, as workers in H. saltator display very low expression levels, particularly of Desat A1, A2, and B. This pattern of functional differentiation among lineages and within species, and the fact that genes stemming from expanded subfamilies do not seem to be essential for survival, fit the expectation of genes involved in the production of semiochemicals, as described for several desaturase genes in D. melanogaster (desat 1, 2, F; Dallerac et al. 2000; Fang et al. 2002; Labeur et al. 2002) and B. mori (Bmpgdesat1; Moto et al. 2004). Changes in the expression and number of acyl-CoA desaturase genes have been shown to affect the diversity of semiochemicals between closely related insect species (Takahashi et al. 2001; Knipple et al. 2002; Roelofs and Rooney 2003; Greenberg et al. 2006; Xue et al. 2007; Fang et al. 2009). "
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