The brain of the female Anopheles gambiae mosquito at spatial and single-cell resolution

Blood feeding in Anopheles mosquitoes is at the root of all malaria infections in humans and is supported by a range of physiological and behavioral adaptations. Since behavior is orchestrated at the level of the central nervous system, we surveyed the cellular diversity and spatial organization of the female Anopheles gambiae brain and compared it to other insect species. We then describe transcriptional changes associated with mosquito life history events with single brain and single-cell RNA sequencing.

We did not identify expansion of specific cell populations, but a modulation of neurotransmission in the mated mosquitoes, and a metabolic and immune response associated with glia, Kenyon cells and immune cells after bloodmeal, and detected signatures of aging in the mosquito brain. We did not find an effect of Plasmodium falciparum infection. Our atlas will empower the study of non-model insect neurobiology, neural basis of vector behavior, and mechanisms underlying malaria transmission.

We are very grateful to Carole Ginibre and the Vectopôle team for providing mosquitoes for these experiments. We would like to thank Marga van de Vegte-Bolmer and Rianne Stoter for generating the P. falciparum parasites and the mosquito infections. We would also like to thank Jolanda Klaassen, Laura Pelser-Posthumus and Astrid Pouwelsen for breeding mosquitoes for the infection experiments.

We acknowledge the support of the MRI core cytometry and imaging facility and the MGX sequencing core facility. We are grateful to Sarrah Loulizi and the HistoPathology platform at Institut Pasteur (Paris) for her help in tissue slicing for the ISH experiments. We are also thankful to Audrey Salles and to the UTechS Photonic BioImaging at Institut Pasteur (Paris) for support in confocal imaging.

We are thankful to Julien Marcetteau for producing illustrative material. We thank Adam Dobson and Ana Gomes for critical reading of the manuscript. This work was supported by a grant from the Parafrap network of excellence awarded to AC (ANR-11-LABX-0024) which supports IZR.

This work was also funded by the RIVOC program from Région Occitanie awarded to AC and AMT (201555PIRIPPLERV06) and by Fondation pour la Recherche Médicale PhD fellowship awarded to IZR (FRM-FDT202404018268) and to SO (FRM-ECO202406019154). This work was supported by the French National Research Institute for Sustainable Development (IRD). These authors contributed equally: Cécile Cassan, Johannes W.