RRC ID 21900
Author Wicker-Thomas C, Guenachi I, Keita YF.
Title Contribution of oenocytes and pheromones to courtship behaviour in Drosophila.
Journal BMC Biochem
Abstract BACKGROUND:In Drosophila, cuticular sex pheromones are long-chain unsaturated hydrocarbons synthesized from fatty acid precursors in epidermal cells called oenocytes. The species D. melanogaster shows sex pheromone dimorphism, with high levels of monoenes in males, and of dienes in females. Some biosynthesis enzymes are expressed both in fat body and oenocytes, rendering it difficult to estimate the exact role of oenocytes and of the transport of fatty acids from fat body to oenocytes in pheromone elaboration. To address this question, we RNAi silenced two main genes of the biosynthesis pathway, desat1 and desatF, in the oenocytes of D. melanogaster, without modifying their fat body expression.
RESULTS:Inactivation of desat1 in oenocytes resulted in a 96% and 78% decrease in unsaturated hydrocarbons in males and females, respectively. Female pheromones (dienes) showed a decrease of 90%. Inactivation of desatF, which is female-specific and responsible for diene formation, resulted in a dramatic loss of pheromones (-98%) paralleled with a two-fold increase in monoenes. Courtship parameters (especially courtship latency) from wild-type males were more affected by desat1 knocked-down females (courtship latency increased by four fold) than by desatF knocked-down ones (+65% of courtship latency).The number of transcripts in oenocytes was estimated at 0.32 and 0.49 attomole/microg for desat1 in males and females, respectively, about half of the total transcripts in a fly. There were only 0.06 attomole/microg desatF transcripts in females, all located in the oenocytes.
CONCLUSION:Knock-down results for desat1 suggest that there must be very little transport of unsaturated precursors from fat body to the oenocytes, so pheromone synthesis occurs almost entirely through the action of biosynthesis enzymes within the oenocytes. Courtship experiments allow us to discuss the behavioral role of diene pheromones, which, under special conditions, could be replaced by monoenes in D. melanogaster. A possible explanation is given of how pheromones could have evolved in species such as D. simulans, which only synthesize monoenes.
Volume 10
Pages 21
Published 2009-8-11
DOI 10.1186/1471-2091-10-21
PII 1471-2091-10-21
PMID 19671131
PMC PMC2734525
MeSH Analysis of Variance Animals Courtship Drosophila Proteins / deficiency Drosophila Proteins / genetics Drosophila Proteins / metabolism Drosophila melanogaster / chemistry Drosophila melanogaster / genetics Drosophila melanogaster / physiology* Epidermal Cells Epidermis / metabolism Fat Body / metabolism Fatty Acid Desaturases / deficiency Fatty Acid Desaturases / genetics Fatty Acid Desaturases / metabolism Female Genes, Insect Genetic Speciation Hydrocarbons / analysis Hydrocarbons / metabolism Male Organ Specificity Pheromones / physiology* RNA Interference RNA, Messenger / chemistry Sex Characteristics Sexual Behavior, Animal / physiology*
IF 1.75
Times Cited 28
Drosophila 5887R-1 5887R-4