title: Visualization and live imaging analysis of a mosquito saliva protein in host animal skin using a transgenic mosquito with a secreted luciferase reporter system.
abstract: Mosquitoes inject saliva into a vertebrate host during blood feeding. The analysis of mosquito saliva in host skin is important for the elucidation of the inflammatory responses to mosquito bites, the development of antithrombotic drugs, and the transmission-blocking of vector-borne diseases. We produced transgenic Anopheles stephensi mosquitoes expressing the secretory luciferase protein (MetLuc) fused to a saliva protein (AAPP) in the salivary glands. The transgene product (AAPP-MetLuc) of transgenic mosquitoes exhibited both luciferase activity as a MetLuc and binding activity to collagen as an AAPP. The detection of luminescence in the skin of mice bitten by transgenic mosquitoes showed that AAPP-MetLuc was injected into the skin as a component of saliva via blood feeding. AAPP-MetLuc remained at the mosquito bite site in host skin with luciferase activity for at least 4 h after blood feeding. AAPP was also suspected of remaining at the site of injury caused by the mosquito bite and blocking platelet aggregation by binding to collagen. These results demonstrated the establishment of visualization and time-lapse analysis of mosquito saliva in living vertebrate host skin. This technique may facilitate the analysis of mosquito saliva after its injection into host skin, and the development of new drugs and disease control strategies.
authors.affiliation: Division of Medical Zoology, Department of Infection and Immunity, Jichi Medical University, Shimotsuke, Japan.
authors.forename: D S
authors.initials: DS
authors.lastname: Yamamoto
authors.forename: T
authors.initials: T
authors.lastname: Yokomine
authors.forename: M
authors.initials: M
authors.lastname: Sumitani
authors.forename: K
authors.initials: K
authors.lastname: Yagi
authors.forename: H
authors.initials: H
authors.lastname: Matsuoka
authors.forename: S
authors.initials: S
authors.lastname: Yoshida
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D000852:Anopheles / Q000235:genetics* / Q000502:physiology; D008156:Luciferases; D008164:Luminescent Proteins; D051379:Mice; D061848:Optical Imaging / Q000379:methods; D012463:Saliva / Q000737:chemistry; D012469:Salivary Glands / Q000737:chemistry; D012867:Skin / Q000737:chemistry*; D059008:Time-Lapse Imaging
chemical_list: D008164:Luminescent Proteins; D008156:Luciferases
keywords: anopheline antiplatelet protein; live imaging; luciferase; mosquito saliva; transgenic mosquito