Proteomics reveals major components of oogenesis in the reproductive tract of sugar-fed Anopheles aquasalis

Abstract

Anopheles (Nyssorhynchus) aquasalis is a malaria vector mainly distributed along the coastal regions of South and Central America. In the absence of an effective vaccine against malaria, strategies for controlling the vector are the main tool for interrupting parasite transmission. Mechanisms of oogenesis and embryogenesis in anautogenous mosquitoes are mainly modulated by blood feeding. However, the expression, at the protein level, of genes involved in such mechanisms in sugar-fed females is unknown. In this work, total protein extracts of the reproductive tract of female An. aquasalis that were fed sugar were analyzed using liquid chromatography followed by mass spectrometry for protein identification and bioinformatic tools for data mining. We identified 922 proteins expressed in the organ, and using several databases, we attributed biological meaning for several of them. Remarkably, nine proteins involved in oogenesis were identified in females fed sugar. Putative vitellogenins, vitellogenin receptor, lipid storage droplet, transferrin, ferritin, and apolipoprotein, identified here, are proteins involved in egg development. Proteins involved in embryonic development, such as paxillin, exuperantia, several growth factors, and dorsal switch protein, were identified. Interestingly, in this study, we identified 15 peptidases of various classes such as aminopeptidases, carboxypeptidases, serine protease, cathepsin, and metalloprotease that could potentially interact with male seminal components. Here, we demonstrated that the reproductive tract of female An. aquasalis fed on sugar expresses proteins involved in oogenesis and embryonic development. These findings reveal unknown aspects of the physiology of this organ under the given nutritional conditions.

Keywords: Anopheles aquasalis; Mass spectrometry; Oogenesis; Proteomics; Reproductive tract.