Biology subjects

Mouillaud, T.

Publications and source records attributed to Mouillaud, T..

3 recordsLinked to original sources

bioRxiv2026

Genotypic evidence of vector-mediated selection on Plasmodium falciparum in infected field-collected Anopheles mosquitoes

Malaria-causing Plasmodium parasites are transmitted between vertebrate hosts via diverse species of Anopheles mosquitoes. The P47 protein in Plasmodium falciparum has been shown to affect transmission in various anopheline species by mediating evasion of mosquito innate immunity in an allele-specific manner. The Pfs47 gene that encodes P47 exhibits high genetic divergence across continents, as well as high genetic diversity within many parasite populations, but the impact of polymorphisms on transmission success in different sympatric vectors has not been previously studied in a field context. Here we report parasite genotyping data from naturally infected, field-collected mosquitoes at sites harboring at least two prevalent sympatric vector species, targeting Pfs47 in addition to the CSP, AMA1, SERA2, and TRAP parasite antigens. Collections took place at Ndangueng, Cameroon and Benguia, Gabon between November 2019 and July 2021, yielding infected Anopheles gambiae at both sites in addition to Anopheles moucheti in Cameroon and Anopheles funestus in Gabon. We found no significant difference in the mean number of parasite strains in infected sympatric mosquito species from each site. However, Pfs47 exhibited a significant difference in the prevalence of an amino acid polymorphism (I248L) between An. moucheti and An. gambiae in Cameroon. Polymorphisms at two additional positions (N272Y/I and P369H) displayed significant linkage disequilibrium with I248L, and there were significant differences in the distribution of Pfs47 haplotypes between sympatric mosquito species at both sites. These findings demonstrate divergent selection on P. falciparum mediated by sympatric vector species, suggesting that parasite genotype significantly impacts local vectorial capacity by modulating species-specific vector competence.

evolutionary biology↗

bioRxiv2025

From macro to micro: De novo genomes of Aedes mosquitoes enable comparative genomics among close and distant relatives

The yellow fever mosquito (Aedes aegypti) is an organism of high medical importance because it is the primary vector for diseases such as yellow fever, Zika, dengue, and chikungunya. Its medical importance has made it a subject of numerous efforts to understand their biology. One such effort, was the development of a high-quality reference genome (AaegL5). However, this reference genome was sourced from a highly inbred laboratory strain with unknown geographic origin. Thus, the reference is not representative of a wild mosquito, let alone one from its native range in sub-Saharan Africa. To better understand the genetic architecture of Ae. aegypti and their sister species, we developed two de novo chromosome-scale genomes with sequences sourced from single individuals: one of Ae. aegypti formosus (Aaf) from Burkina Faso and one of Ae. mascarensis (Am) from Mauritius. Both genomes exhibit high contiguity and gene completeness, comparable to AaegL5. While Aaf exhibits high degree of synteny to AaegL5, it also exhibits several large inversions. We further conducted comparative genomic analyses using our genomes and other publicly available culicid reference genomes to find extensive chromosomal rearrangements between major lineages. Overrepresentation analysis of expanded genes in Aaf, AaegL5, and Am revealed that while the overarching category of genes that have expanded are similar, the specific genes that have expanded differ. Our findings elucidate novel insights into chromosome evolution at both microevolutionary and macroevolutionary scales. The genomic resources we present are additions to the arsenal of biologists in understanding mosquito biology and genome evolution. SignificanceAedes aegypti is a major arboviral disease vector found throughout the tropics and sub-tropics. Its subspecies differ ecologically, as native sub-Saharan African form feeds on mammals generally and inhabit both sylvatic and domestic areas and the global invasive form preferentially feeds on humans and lives primarily domestic areas. Their medical importance has prompted the development of a high-quality reference genome, but it was sourced from an inbred laboratory strain of unknown origin. Here, we leveraged PacBio HiFi sequencing and HiC sequencing to develop the first de novo genome of Ae. aegypti sampled its native range in Burkina Faso. We also present a de novo genome of Ae. mascarensis, its sister species. Our genomes are comparably contiguous and complete to the reference genome. Comparative genomic analysis using our genomes and other culicid reference genomes reveal extensive chromosomal rearrangements.

genomics↗

bioRxiv2023

No Wolbachia protection against Plasmodium falciparum infection in the major malaria mosquito Anopheles moucheti

Since the discovery of natural malaria vector populations infected by the endosymbiont bacterium Wolbachia, a renewed interest has arisen for using this bacterium as an alternative for malaria control. Among naturally infected mosquitoes, Anopheles moucheti, a major malaria mosquito in Central Africa, exhibits one of the highest prevalences of Wolbachia infection. To better understand whether this maternally inherited bacterium could be used for malaria control, we investigated Wolbachia influence in An. moucheti populations naturally infected by the malaria parasite Plasmodium falciparum. To this end, we collected mosquitoes in a village from Cameroon, Central Africa, where this mosquito is the main malaria vector. We found that the prevalence of Wolbachia bacterium was almost fixed in the studied mosquito population, and was higher than previously recorded. We also quantified Wolbachia in whole mosquitoes and dissected abdomens, confirming that the bacterium is also elsewhere than in the abdomen, but at lower density. Finally, we analyzed the impact of Wolbachia presence and density on P. falciparum infection. Wolbachia density was slightly higher in mosquitoes infected with the malaria parasite than in uninfected mosquitoes. However, we observed no correlation between the P. falciparum and Wolbachia densities. In conclusion, our study indicates that naturally occurring Wolbachia infection does not affect P. falciparum development within An. moucheti mosquitoes.

microbiology↗