Project description:Sib mating increase homozygosity and can lead to inbreeding depression. Selective pressures have favored the evolution of kin recognition and sib avoidance in mate choice. Such avoidance behavior has been recorded in the parasitoid wasp Venturia canescens where the sex determining system (single-locus complementary sex determination, sl-csd) introduces an extra short-term cost to inbreeding; females preferentially mate with unrelated males. The genetics underlying mate choice of females and kin recognition remains largely unexplored. Here we analyzed the head transcriptomic changes after exposure to distinct stimulus: courtship by unrelated male or courtship by brother, while transcriptome of females alone was used as control. Our results demonstrate that male courtship provokes a major transcriptome reprogramming in females heads. The transcriptomic response is highly dependent on the compatibility of the courting male. We subdivided the socially responsive genes using an integrative gene network analysis, we highlighted genes regulated by courtship, whatever the relatedness of the courting male. We also showed that the regulation of some peculiar group of genes is very specific of compatible male courtship, while others are regulated only by incompatible male courtship. We suggest that those different transcriptomic responses lead to mating decision or sib mating avoidance behavior observed in this species.
Project description:Female Aedes aegypti mosquitoes impose a severe global public health burden as primary vectors of multiple viral and parasitic pathogens. Under optimal environmental conditions, Aedes aegypti females have access to human hosts that provide blood proteins for egg development, conspecific males that provide sperm for fertilization, and freshwater that serves as an egg-laying substrate suitable for offspring survival. As global temperatures rise, Aedes aegypti females are faced with climate challenges, like intense droughts and intermittent precipitation, which create unpredictable and suboptimal conditions for the egg-laying step of their reproductive cycle. Aedes aegypti mosquitoes nonetheless show remarkable reproductive resilience, but how they achieve this is unknown. Here we show that under drought-like conditions simulated in the laboratory, mated, blood-fed Aedes aegypti females carrying mature eggs retain them in their ovaries for extended periods, while maintaining the viability of these eggs until they can be deposited in freshwater. Using transcriptomic and proteomic profiling of Aedes aegypti ovaries, we identify two previously uncharacterized genes – here named tweedledee and tweedledum – that show ovary-enriched, temporally-restricted expression during egg retention. These genes are mosquito-specific, linked within a syntenic locus, and rapidly evolving under positive selection, raising the possibility that they serve an adaptive function. Using loss-of-function mutagenesis to disrupt both genes, we show that, tweedledee and tweedledum, which encode secreted proteins, are specifically required for extended retention of viable eggs, such as during intermittent precipitation or drought. These results highlight an elegant example of taxon-restricted genes at the heart of an important adaptation that equips Aedes aegypti females with “insurance” to, when contextually appropriate, flexibly extend their reproductive sequence without losing reproductive capacity, thus allowing this species to exploit diverse and unpredictable habitats.
Project description:Globally invasive Aedes aegypti mosquitoes disseminate numerous arboviruses that impact human health. One promising method to control Ae. aegypti populations is transinfection with the intracellular bacterium Wolbachia pipientis, a symbiont that naturally infects ~40-52% of insects but is normally absent from Ae. aegypti. Transinfection of Ae. aegypti with the wMel Wolbachia strain induces cytoplasmic incompatibility (CI), allowing infected individuals to rapidly invade native populations. Further, wMel Wolbachia-infected females display refractoriness to medically relevant arboviruses. Thus, wMel Wolbachia-infected Ae. aegypti are being released in several areas to replace native populations, thereby suppressing disease transmission by this species. Wolbachia is reported to have minimal effects on Ae. aegypti fertility, but its influence on other reproductive processes is unknown. Female insects undergo several post-mating physiological and behavioral changes required for optimal fertility. Post-mating responses (PMRs) in female insects are typically elicited by receipt of male seminal fluid proteins (SFPs) transferred with sperm during mating, but can be modified by other factors, such as adult age, nutritional status, and microbiome composition. To assess how Wolbachia infection influences Ae. aegypti female PMRs, we collected wMel Wolbachia-infected Ae. aegypti from the field in Medellín, Colombia and introduced the bacterium into our laboratory strain. We found that Wolbachia influences female fecundity, fertility, and re-mating incidence. Further, we observed that Wolbachia significantly extends longevity of virgin females. Changes in female PMRs are not due to defects in sperm transfer by infected males, or sperm storage by infected females. Using proteomic methods to examine the seminal proteome of infected males, we found that Wolbachia infection has a moderate effect on SFP composition. However, we identified 125 Wolbachia proteins that are paternally transferred to females by infected males. Surprisingly, the CI factor proteins (Cifs), were not detected in the ejaculates of Wolbachia-infected males. Our findings indicate that Wolbachia infection of Ae. aegypti alters female post-mating responses, potentially influencing control programs that utilize Wolbachia-infected individuals.
Project description:Female Aedes aegypti mosquitoes impose a severe global public health burden as primary vectors of multiple viral and parasitic pathogens. Under optimal environmental conditions, Aedes aegypti females have access to human hosts that provide blood proteins for egg development, conspecific males that provide sperm for fertilization, and freshwater that serves as an egg-laying substrate suitable for offspring survival. As global temperatures rise, Aedes aegypti females are faced with climate challenges, like intense droughts and intermittent precipitation, which create unpredictable and suboptimal conditions for the egg-laying step of their reproductive cycle. Aedes aegypti mosquitoes nonetheless show remarkable reproductive resilience, but how they achieve this is unknown. Here we show that under drought-like conditions simulated in the laboratory, mated, blood-fed Aedes aegypti females carrying mature eggs retain them in their ovaries for extended periods, while maintaining the viability of these eggs until they can be deposited in freshwater. Using transcriptomic and proteomic profiling of Aedes aegypti ovaries, we identify two previously uncharacterized genes – here named tweedledee and tweedledum – that show ovary-enriched, temporally-restricted expression during egg retention. These genes are mosquito-specific, linked within a syntenic locus, and rapidly evolving under positive selection, raising the possibility that they serve an adaptive function. Using loss-of-function mutagenesis to disrupt both genes, we show that, tweedledee and tweedledum, which encode secreted proteins, are specifically required for extended retention of viable eggs, such as during intermittent precipitation or drought. These results highlight an elegant example of taxon-restricted genes at the heart of an important adaptation that equips Aedes aegypti females with “insurance” to, when contextually appropriate, flexibly extend their reproductive sequence without losing reproductive capacity, thus allowing this species to exploit diverse and unpredictable/chaotic/changing habitats.
Project description:We report the RNA-seq based analyses of the transcriptional changes in the Aedes aegypti transcriptome 5 hours after blood feeding. Comparison of the transcriptome of Aedes aegypti females at two physiological conditions and one time point.
Project description:This analysis compare gene expression between 4 day old sugar fed female and male Aedes aegypti mosquitoes. Keywords: Aedes aegypti sex specific expression
Project description:Investigation of whole genome gene expression level changes of testes in the meiotic drive system in aedes aegypti during spermatogenesis compared to non drive strain. The meiotic drive system in Aedes aegypti causes the female determining chromosome to fragment during spermatogenesis. A six chip study using total RNA from three separately extracted non driving strain testes of Aedes aegypti and three separately extracted meiotic drive strain testes of Aedes aegypti.
Project description:We reported the RNA-seq based analyses of the transcriptional changes in the Aedes aegypti midguts knock down 3, 6days, feed antibody 18h transcriptome. Comparison of the midguts transcriptome of Aedes aegypti females at two knockdown time points and one feed condition; GFP dsRNA-3 or -6days: 3 or 6 days after 7day-old mosquitos were microinjected GFP dsRNA AaMesh dsRNA-3 or -6days: 3 or 6 days after 7day-old mosquitos were microinjected AaMesh dsRNA Pre-immune-18h: 18hrs after 7day-old wild type mosquitos were fed with Pre-immune AaMesh antibody-18h: 18hrs after 7day-old wild type mosquitos were fed with AaMesh antibody
Project description:Investigation of whole genome gene expression level changes of testes in the meiotic drive system in aedes aegypti during spermatogenesis compared to non drive strain. The meiotic drive system in Aedes aegypti causes the female determining chromosome to fragment during spermatogenesis.