Bacteria of the genus Asaia are associated with different species of malaria vectors and are located in the midgut, salivary glands and reproductive organs of female and male mosquitoes. Based on current evidence, the spreading of these bacteria in mosquito populations occurs through different mechanisms: co-feeding, sexual mating, and maternal transmission [1,2]. Even though paternal transmission of insect symbionts to progeny is not commonplace, the presence of Asaia in the male reproductive organs makes this additional transmission route worth being investigated. Here, we show that male-borne Asaia are transferred to females during the mating of Anopheles stephensi mosquitoes. Subsequently, the bacteria acquired by the female are vertically transmitted to the progeny. It would thus be possible to use male mosquitoes, which do not bite, to spread Asaia strains interfering with malaria transmission.
Bibliographical noteFunding Information:
C.D. and I.R. equally contributed to this work. Partial financial contribution comes form the Italian Ministry for Research (MIUR), ‘Finanziamenti PRIN 2007’. I.R. was funded by ‘Compagnia San Paolo’ in the context of the Italian Malaria Network. E.C., P.R., C.B. and D.D. benefited from travel grants from Cost Action FA0701: ‘Arthropod Symbiosis: From Fundamental Studies to Pest and Disease Management’. We thank Nathan Lo and Cristina Miceli for critical review of the manuscript.
ASJC Scopus subject areas
- General Biochemistry, Genetics and Molecular Biology
- General Agricultural and Biological Sciences