Search results for "hydrocarbon"
showing 10 items of 637 documents
Genetic study of the production of sexually dimorphic cuticular hydrocarbons in relation with the sex-determination gene transformer in Drosophila me…
2002
In Drosophila melanogaster, the main cuticular hydrocarbons (HCs) are some of the pheromones involved in mate discrimination. These are sexually dimorphic in both their occurrence and their effects. The production of predominant HCs has been measured in male and female progeny of 220 PGal4 lines mated with the feminising UAS-transformer transgenic strain. In 45 lines, XY flies were substantially or totally feminised for their HCs. Surprisingly, XX flies of 14 strains were partially masculinised. Several of the PGal4 enhancer-trap variants screened here seem to interact with sex determination mechanisms involved in the control of sexually dimorphic characters. We also found a good relationsh…
Regulation of cuticular hydrocarbon profile maturation by Drosophila tanning hormone, bursicon, and its interaction with desaturase activity
2016
International audience; Shortly after emergence the exoskeleton (cuticle) of adult insects is rapidly expanded, hardened (sclerotized), and pigmented (melanized). In parallel with this process, the oenocytes, which are large polyploid cells located below the abdominal epidermis, secrete onto the cuticle a cocktail of cuticular hydrocarbons (CHs) and waxes. These improve the waterproofing of the cuticle, and also provide important chemosensory and pheromonal cues linked with gender, age, and species differentiation. The hardening and pigmentation of the new cuticle are controlled by the neurohormone, bursicon, and its receptor, encoded by the DLGR2 receptor, rickets (rk); by contrast, little…
Dietary rescue of altered metabolism gene reveals unexpected [i]Drosophila[/i] mating cues
2015
Running title: Dietary rescue of metabolic mutation and reproduction; To develop and reproduce, animals need long-chain Mono and PolyUnsaturated Fatty Acids (MUFAs; PUFAs). Although some UFAs can be synthesized by the organism, others must be provided by the diet. The gene desat1, involved in Drosophila melanogaster UFA metabolism, is necessary for both larval development and for adult sex pheromone communication. We first characterized desat1 expression in larval tissues. Then, we found that larvae in which desat1 expression was knocked down throughout development died during the larval stages when raised on standard food. By contrast pure MUFAs or PUFAs, but not saturated FAs, added to th…
A Mutation With Major Effects on Drosophila melanogaster Sex Pheromones
2005
0016-6731 (Print) Comparative Study Journal Article Research Support, Non-U.S. Gov't; Sex pheromones are intraspecific chemical signals that are crucial for mate attraction and discrimination. In Drosophila melanogaster, the predominant hydrocarbons on the cuticle of mature female and male flies are radically different and tend to stimulate or inhibit male courtship, respectively. This sexual difference depends largely upon the number of double bonds (one in males and two in females) added by desaturase enzymes. A mutation was caused by a PGal4 transposon inserted in the desat1 gene that codes for the desaturase crucial for setting these double bonds. Homozygous mutant flies produced 70-90%…
The consequences of regulation of desat1 expression for pheromone emission and detection in Drosophila melanogaster.
2010
AbstractSensory communication depends on the precise matching between the emission and the perception of sex- and species-specific signals; understanding both the coevolutionary process and the genes involved in both production and detection is a major challenge. desat1 determines both aspects of communication—a mutation in desat1 simultaneously alters both sex pheromone emission and perception in Drosophila melanogaster flies. We investigated whether the alteration of pheromonal perception is a consequence of the altered production of pheromones or if the two phenotypes are independently controlled by the same locus. Using several genetic tools, we were able to separately manipulate the tw…
Sensitive determination of polycyclic aromatic hydrocarbons in water samples using monolithic capillary solid-phase extraction and on-line thermal de…
2011
A methacrylate-based monolithic capillary column has been evaluated for the preconcentration of polycyclic aromatic hydrocarbons (PAHs) from environmental water samples. For this purpose, the monolyte was in situ synthesized in a 6cm×0.32mm id fused-silica capillary. The microextraction unit was fitted to a micro-HPLC pump to pass 10mL of sample. The isolated pollutants were eluted by means of 10μL of methanol, the organic phase being directly collected in a specific interface that can be fitted to the injection port of the gas chromatograph without modification. The interface allows the on-line thermal desorption of the PAHs, avoiding the dilution and providing enough sensitivity to reach …
Ventilation-Perfusion Ratio in Perflubron During Partial Liquid Ventilation
2010
BACKGROUND: Functional magnetic resonance imaging (fMRI) of fluorine-19 allows for the mapping of oxygen partial pressure within perfluorocarbons in the alveolar space (Pao(2)). Theoretically, fMRI-detected Pao(2) can be combined with the Fick principle approach, i.e., a mass balance of oxygen uptake by ventilation and delivery by perfusion, to quantify the ventilation-perfusion ratio (Va/Q) of a lung region: The mixed venous blood and the inspiratory oxygen fraction, which are equal for all lung regions, are measured. In addition, the local expiratory oxygen fraction and the end capillary oxygen content, both of which may differ between the lung regions, are calculated using the fMRI-detec…
The buried Fold and Thrust Belt in Sicily: perspectives for future exploration.
2012
The study region is a part of the Sicilian-Maghrebian Fold and Thrust Belt (FTB), a segment of the Alpine collisional belt, recently described as a result of both post-collisional convergence between Africa and Europe and roll-back of the subduction hinge of the Ionian lithosphere. The region (extending in central Sicily from the Madonie Mountains. to the eastern corner of the Iblean-Pelagian foreland through the impressive NE-SW trending Tertiary clastic and evaporitic range of the Caltanissetta trough) is located in an area where the main thrust system disappears beneath a wedge of deformed Neogene deposits. Earlier studies have neglected the importance of the potential target for hydroca…
Analysis of Chemical and Biochemical Parameters of Petrol-Contaminated Soil after Biostimulation with an Enzyme Reagent
2020
This study aimed to assess the effect of petrol and the Fyre Zyme reagent on selected chemical and biochemical properties of loamy sand. The experiment was conducted under laboratory conditions. First, petrol was introduced into the soil at doses of 0 and 50 g k-1dry matter (DM). Next, 6% Fyre-Zyme enzyme reagent solution was added to the samples contaminated and uncontaminated with petrol, in the following combinations: 0 (control), once at 40 cm3 kg&ndash
Isomer-nonspecific action of dichlorodiphenyltrichloroethane on aryl hydrocarbon receptor and G-protein-coupled receptor 30 intracellular signaling i…
2014
Abstract Extended residual persistence of the pesticide dichlorodiphenyltrichloroethane (DDT) raises concerns about its long-term neurotoxic effects. Little is known, however, about DDT toxicity during the early stages of neural development. This study demonstrated that DDT-induced apoptosis of mouse embryonic neuronal cells is a caspase-9-, caspase-3-, and GSK-3β-dependent process, which involves p,p’ -DDT-specific impairment of classical ERs. It also provided evidence for DDT-isomer-nonspecific alterations of AhR- and GPR30-mediated intracellular signaling, including changes in the levels of the receptor and receptor-regulated mRNAs, and also changes in the protein levels of the receptors…