The mosquito salivary glands: Transcriptome, RNAi and Salivary antigens.

We have recently completed an Anopheles gambiae salivary gland transcriptome analysis that allowed for the assembly of a catalogue of approximately 70 bona fide secreted proteins. The saliva of hematophagous arthropods contains several pharmacological activities that can affect both human physiological responses (hemostatic, inflammatory, immune) and pathogen transmission. Only little is known about mosquito salivary components and about half of the putative salivary proteins identified so far are without known function. In order to proceed toward a functional analysis we are establishing conditions to obtain efficient and reproducible silencing of salivary genes. This would be a useful tool to investigate the possible involvement of salivary genes in parasite transmission and to test candidate sporozoite receptors. Moreover, comparative analysis of available mosquito salivary transcriptomes highlighted that whereas several salivary genes/proteins are common to different mosquito species other are found exclusively either in anophelinae or in culicinae. This may have interesting implications because immunogenic Anopheles-specific salivary antigens may be of use as markers of exposure to Anopheles bites in malaria epidemiological studies