Deletion of the Drosophila neuronal gene found in neurons disrupts brain anatomy and male courtship.

The fne (found-in-neurons) locus encodes one of the three paralogs of the ELAV gene family of Drosophila melanogaster. Members of this family are found throughout metazoans and encode RNA-binding proteins with primarily neuronal localization, but with remarkably diverse functions given their high level of amino acid sequence conservation. The first identified member of the family, elav of Drosophila is a vital gene.

Ontogeny of Drosophila melanogaster female sex-appeal and cuticular hydrocarbons.

The chemical communication system in Drosophila melanogaster Meigen, 1830 plays a major role in courtship and consists of the male-specific cis-Vaccenyl acetate and sex-specific contact pheromones, cuticular hydrocarbons (CHC), which build up during ontogeny (first 4 days). They replace longer CHCs, common to both sexes and present only after the imaginal eclosion. A detailed quantitative description of the evolution of cuticular unsaturated hydrocarbons with age is presented here for males and females of different D.

Germline-dependent gene expression in distant non-gonadal somatic tissues of Drosophila.

Background: Drosophila females commit tremendous resources to egg production and males produce some of the longest sperm in the animal kingdom. We know little about the coordinated regulation of gene expression patterns in distant somatic tissues that support the developmental cost of gamete production.

Results: We determined the non-gonadal gene expression patterns of Drosophila females and males with or without a germline.

Evolution of cuticular hydrocarbons of Hawaiian Drosophilidae.

Hawaiian Drosophila offer an excellent model for adaptive evolution. More than 500 species are reported in Hawaiian islands, and there is considerable diversity in behavior and morphology. Such diversity is mainly driven by sexual selection.

Genetic analysis of cuticular hydrocarbons and their effect on courtship in Drosophila virilis and D. lummei.

Genetical factors controlling the cuticular hydrocarbons (CHC) of Drosophila virilis and D. lummei, and the effect of CHC on female attractivity were studied. A strong sexual dimorphism was found in D.

Role of the ejaculatory bulb in biosynthesis of the male pheromone cis-vaccenyl acetate in Drosophila melanogaster.

In Drosophila melanogaster, the male ejaculatory bulb is the site of synthesis of a male-specific pheromone, cis-vaccenyl acetate, which functions as both an attractant and an anti-aphrodisiac. This long monounsaturated acetate is structurally similar to a number of shorter gland-synthesized moth pheromones. The cell monolayer that forms the Drosophila male ejaculatory bulb wall is responsible for the production and secretion of cis-vaccenyl acetate into the seminal fluid.

Quantitative trait loci for cuticular hydrocarbons associated with sexual isolation between Drosophila simulans and D. sechellia.

The identification of genes with large effects on sexual isolation and speciation is an important link between classic evolutionary genetics and molecular biology. Few genes that affect sexual isolation and speciation have been identified, perhaps because many traits influencing sexual isolation are complex behaviors. Cuticular hydrocarbons (CHs) of species of the Drosophila melanogaster group play a large role in sexual isolation by functioning as contact pheromones influencing mate recognition.

Sexual isolation and cuticular hydrocarbon differences between Drosophila santomea and Drosophila yakuba.

Drosophila santomea and Drosophila yakuba are two sister species inhabiting Saõ Tomé island. Previous studies showed that both species display strong reproductive isolation, although they can produce a few viable hybrids. Our study tried to understand the mechanism of this ethological isolation between two allopatric strains.

Role of cuticular hydrocarbons in the chemical recognition between ant species in the Pachycondyla villosa species complex.

Cuticular hydrocarbons (HCs) play important roles in insect communication but few studies clearly demonstrate the direct link between HCs and nestmate recognition. Therefore, cuticular lipids were extracted from ants, their HC and non-HC fractions as well as the three principal classes of HCs (n-alkanes, branched alkanes and alkenes) were purified and tested using an immobilizing "joust" device which allowed quantification of early pairwise behavioural responses, mandibular opening and antennal retraction, without occurrence of subsequent damages as in classic dyadic encounters. Chemical recognition of ants was studied at three levels of interactions (intra-colonial, intra-specific and inter-specific).

Female-specific regulation of cuticular hydrocarbon biosynthesis by dopamine in Drosophila melanogaster.

The role of dopamine (DA) is investigated in cuticular hydrocarbon biosynthesis in Drosophila melanogaster with three different approaches: use of DA-deficient mutants (dopa decarboxylase temperature sensitive mutants reared at restrictive temperature, and rescued by dopamine ingestion or by pale mutants partially rescued by a tyrosine hydroxylase construction), pharmacological treatments (tyrosine hydroxylase inhibitors) and topical application on decapitated flies. We report that DA specifically regulates diene hydrocarbon biosynthesis, which is female specific. Our results suggest that DA acts in adult flies within the first hours of imaginal life and that DA production from the brain is crucial for this process.

Hydrocarbon circulation and colonial signature in Pachycondyla villosa.

In ants, both cuticular and postpharyngeal gland (PPG) hydrocarbons (HCs) have been involved in nestmate recognition. However, no detailed comparison is available. A comparative study including also high density lipophorin (HDLp), an internal HC carrier, was therefore undertaken on Pachycondyla villosa.

Why there is a one-way crossability between D. melanogaster and D. simulans? An ontogenic explanation.

In the Drosophila melanogaster complex, females D. melanogaster mate relatively easily with males Drosophila simulans but the reciprocal cross is rare. The species sexual isolation is mainly based on chemical and acoustic signal exchanges between partners.

Relations between cuticular hydrocarbon (HC) polymorphism, resistance against desiccation and breeding temperature; a model for HC evolution in D. melanogaster and D. simulans.

D. simulans and D. melanogaster present two types of polymorphism in their cuticular hydrocarbon (HC) composition.

Incorporation of fatty acids into cuticular hydrocarbons of male and female Drosophila melanogaster.

The biosynthesis of cuticular hydrocarbons was investigated in male and female Drosophila melanogaster (Canton-S strain), especially in those with a pheromonal role i.e. male 7-tricosene and female 7, 11- heptacosadiene.

Reproductive isolation in natural populations of Drosophila melanogaster from Brazzaville (Congo).

The aim of this work is to analyze the homogamy previously detected between two natural populations of Drosophila melanogaster from Brazzaville. It is shown that mating isolation was still maintained under laboratory conditions 10 years after the populations samples were trapped. Isolation seemed to be due mainly to premating isolation and we checked for any suggestion of post-mating mortality of hybrids.

Control of female pheromones in Drosophila melanogaster by homeotic genes.

We have investigated the role of the Antennapedia and Bithorax complexes (ANT-C and BX-C) on the production of cuticular hydrocarbons in Drosophila melanogaster. In males, there is little, if any, influence of these complexes on the hydrocarbon pattern. In females, there are large and opposite effects of these complexes on diene production: two ANT-C mutations cause an increase in diene production and a reduction of monoenes, whereas most BX-C mutations result in a decrease in dienes and an increase in monoenes, although their sum remains constant.

Compared ontogenesis of courtship song components of males from the sibling species, D. melanogaster and D. simulans.

The courtship song of Drosophila is known to be an important signal involved in sex and species recognition. It consists of pulse song and sine song, which have been studied in a quantitative way with different parameters. For the first time the setting of both components of the acoustic signaling is described and compared for males belonging to the sibling species D.

Variations of male cuticular hydrocarbons with geoclimatic variables: an adaptative mechanism in Drosophila melanogaster?

7-tricosene (7T) and 7-pentacosene (7P) are the major components of cuticular hydrocarbons in Drosophila simulans and D. melanogaster males. A chemical study of 16 isofemale lines of D.

A delta 9 desaturase gene with a different substrate specificity is responsible for the cuticular diene hydrocarbon polymorphism in Drosophila melanogaster.

Drosophila melanogaster cuticular pheromones consist of unsaturated hydrocarbons with at least one double bond in position 7: 7 tricosene (T) in males and 7,11 heptacosadiene (HD) in females. However, in many African populations like the Tai strain, females possess low levels of 7,11 HD and high levels of its positional isomer 5,9 HD. We have previously isolated a desaturase gene, desat1, from the Canton-S strain (CS), a 7,11 HD-2-rich morph of D.

Sexual isolation of genetically differentiated sympatric populations of Drosophila melanogaster in Brazzaville, Congo: the first step towards speciation?

Two sympatric populations of Drosophila melanogaster were collected in the Brazzaville area in Congo, one from the suburban countryside and the other from a brewery located in the city. They were compared for several genetically determined traits including morphology, allozymes, microsatellites, cuticular hydrocarbons, and sexual behaviour. The two populations were similar to other African populations for morphological traits, but differed significantly from each other for all other characters.

Role of Enhancer of zeste on the production of Drosophila melanogaster pheromonal hydrocarbons.

In a search for genes controlling the production of Drosophila melanogaster contact pheromones, the gene Enhancer of zeste [E(z)] was found to be one player. Flies mutant for either the amorphic or the antimorphic allele of E(z) showed a similar hydrocarbon phenotype as those with the overlapping Df lxd(15) deficiency: decreased amounts of total hydrocarbons and especially unsaturated ones in both sexes. The decrease in the level of D.

A gene responsible for a cuticular hydrocarbon polymorphism in Drosophila melanogaster.

Drosophila melanogaster is polymorphic for the major cuticular hydrocarbon of females. In most populations this hydrocarbon is 7,11-heptacosadiene, but females from Africa and the Caribbean usually possess low levels of 7,11-heptacosadiene and high quantities of its position isomer 5,9-heptacosadiene. Genetic analysis shows that the difference between these two morphs is due to variation at a single segregating factor located on the right arm of chromosome 3 near map position 51.

Sexual behaviour in Drosophila is irreversibly programmed during a critical period.

Sexual differentiation in Drosophila is controlled by a short cascade of regulatory genes, the expression pattern of which determines all aspects of maleness and femaleness, including complex behaviours displayed by males and females [1-3]. One sex-determining gene is transformer (tra), the activity of which is needed for female development. Flies with a female karyotype (XX) but which are mutant for tra develop and behave as males.

Genetic feminization of pheromones and its behavioral consequences in Drosophila males.

Pheromones are intraspecific chemical signals important for mate attraction and discrimination. In the fruit fly Drosophila melanogaster, hydrocarbons on the cuticular surface of the animal are sexually dimorphic in both their occurrence and their effects: Female-specific molecules stimulate male sexual excitation, whereas the predominant male-specific molecule tends to inhibit male excitation. Complete feminization of the pheromone mixture produced by males was induced by targeted expression of the transformer gene in adult oenocytes (subcuticular abdominal cells) or by ubiquitous expression during early imaginal life.