title: Frizzled 2 is a key component in the regulation of TOR signaling-mediated egg production in the mosquito Aedes aegypti.
abstract: The Wnt signaling pathway was first discovered as a key event in embryonic development and cell polarity in Drosophila. Recently, several reports have shown that Wnt stimulates translation and cell growth by activating the mTOR pathway in mammals. Previous studies have demonstrated that the Target of Rapamycin (TOR) pathway plays an important role in mosquito vitellogenesis. However, the interactions between these two pathways are poorly understood in the mosquito. In this study, we hypothesized that factors from the TOR and Wnt signaling pathways interacted synergistically in mosquito vitellogenesis. Our results showed that silencing Aedes aegypti Frizzled 2 (AaFz2), a transmembrane receptor of the Wnt signaling pathway, decreased the fecundity of mosquitoes. We showed that AaFz2 was highly expressed at the transcriptional and translational levels in the female mosquito 6 h after a blood meal, indicating amino acid-stimulated expression of AaFz2. Notably, the phosphorylation of S6K, a downstream target of the TOR pathway, and the expression of vitellogenin were inhibited in the absence of AaFz2. A direct link was found in this study between Wnt and TOR signaling in the regulation of mosquito reproduction.
authors.affiliation: Department of Parasitology, National Taiwan University, Taipei, Taiwan.
authors.forename: Shih-Che
authors.initials: SC
authors.lastname: Weng
authors.affiliation: Department of Parasitology, National Taiwan University, Taipei, Taiwan. Electronic address: shshiao@ntu.edu.tw.
authors.forename: Shin-Hong
authors.initials: SH
authors.lastname: Shiao
mesh_terms: D000330:Aedes / Q000235:genetics / Q000502:physiology*; D000818:Animals; D005260:Female; D051157:Frizzled Receptors / Q000235:genetics / Q000378:metabolism*; D009928:Organ Specificity; D010063:Ovum / Q000254:growth & development; D010766:Phosphorylation; D034622:RNA Interference; D019893:Ribosomal Protein S6 Kinases / Q000378:metabolism; D015398:Signal Transduction; D058570:TOR Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism; D014818:Vitellogenesis; D014819:Vitellogenins / Q000235:genetics / Q000378:metabolism
chemical_list: D051157:Frizzled Receptors; D014819:Vitellogenins; D019893:Ribosomal Protein S6 Kinases; D058570:TOR Serine-Threonine Kinases
keywords: Aedes aegypti; Fecundity; TOR; Vitellogenesis; Wnt