Mutations in the desat 1 gene reduce the production of courtship stimulatory pheromones through a marked effect on fatty acids in Drosophila melanogaster.

Laboratoire de Neurobiologie de l'Apprentissage, de la Mémoire et de la Communication, CNRS UMR 8620, Bât. 446, Université Paris-Sud, 91405 Orsay Cédex, France.
Insect Biochemistry and Molecular Biology (Impact Factor: 3.45). 09/2005; 35(8):911-20. DOI: 10.1016/j.ibmb.2005.03.007
Source: PubMed


In Drosophila melanogaster, desat1 is involved in the synthesis of fatty acids (FAs), some of which are precursors in the production of unsaturated hydrocarbons (HCs) in position 7 (7-HC) that play an important role in mating behaviour. Three GS lines with P-element insertion in the desat1 promoter showed more or less decrease in 7-HC, depending on the site of insertion. The forced transcription of genomic 5'P-flanking sequence led to opposite effects upon 7-HC, depending on the orientation of the insertions. Homozygous GS12251 flies showed particularly low 7-HC levels and severely affected courtship parameters (courtship latency doubled, number of copulation attempts decreased by half). After transposon excision, the HC phenotype was reversed in most lines, showing that the location of the transposon was responsible for the mutant phenotype. In homozygous GS12251 flies, the amounts of FAs and desat1 transcripts were reduced by half, compared to the amounts in heterozygous or wild-type flies. Relative proportions among FAs were quite similar to those of wild-type, with the exception of a slight decrease in myristoleic, palmitoleic and vaccenic acid. As the reduction of desat1 activity in the mutant resulted in a large decrease in both unsaturated and saturated FAs, it could impair FA and lipid metabolism, as it is known in vertebrates.

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Available from: Claude Wicker-Thomas, Feb 06, 2015
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    • "e males pro - duce monoenes that have been shown to inhibit courtship from other males ( Jallon 1984 ; Foley et al . 2007 ; Wicker - Thomas 2007 ; Arienti et al . 2010 ) . Two desaturases are involved in CH production : the enzyme Desat1 , is expressed in males and females , both in the oenocytes and in the fat body ( Marcillac et al . 2005a , b ; Ueyama et al . 2005 ; Bousquet et al . 2009 , 2012 ) , and DesatF , pathway involving detection of cVA . The first olfactory receptor identified for detection of cVA was OR67d . However , this receptor protein does not act alone to trigger a response to cVA . Instead , it functions in a complex formed by cVA and several proteins including the extra - cellu"
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    ABSTRACT: Upon encountering a conspecific in the wild, males have to rapidly detect, integrate and process the most relevant signals to evoke an appropriate behavioral response. Courtship and aggression are the most important social behaviors in nature for procreation and survival: for males, making the right choice between the two depends on the ability to identify the sex of the other individual. In flies as in most species, males court females and attack other males. Although many sensory modalities are involved in sex recognition, chemosensory communication mediated by specific molecules that serve as pheromones plays a key role in helping males distinguish between courtship and aggression targets. The chemosensory signals used by flies include volatile and non-volatile compounds, detected by the olfactory and gustatory systems. Recently, several putative olfactory and gustatory receptors have been identified that play key roles in sex recognition, allowing investigators to begin to map the neuronal circuits that convey this sensory information to higher processing centers in the brain. Here, we describe how Drosophila melanogaster males use taste and smell to make correct behavioral choices.
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    • "Hence, the application of insect models to the investigation of the basic questions related to lipid storage and mobilization will be an important reference [38]. In insects, a change in the fatty acid content can affect female fecundity [41] [10] and remating [42], as well as their production of sex pheromones [43]. In addition, the lipid was the primary fuel during metamorphosis, which accounted for >80% of the total metabolism [44]. "
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