Universidade de São Paulo, Instituto de Ciências Biomédicas, Departamento de Parasitologia, São Paulo, SP, Brasil.
Florida International University, Sciences Institute, Department of Biological Sciences & Biomolecular, Miami, FL, USA.
Mem Inst Oswaldo Cruz. 2023 Jul 17;118:e220143. doi: 10.1590/0074-02760220143. eCollection 2023.
Culex quinquefasciatus, a cosmopolitan, domestic, and highly anthropophilic mosquito, is a vector of pathogenic arboviruses such as West Nile virus and Rift Valley virus, as well as lymphatic filariasis. The current knowledge on its reproductive physiology regarding vitellogenin expression in different tissues is still limited.
In this study, we analysed the transcriptional profiles of vitellogenin genes in the fat body and ovaries of C. quinquefasciatus females during the first gonotrophic cycle.
C. quinquefasciatus ovaries and/or fat bodies were dissected in different times during the first gonotrophic cycle and total RNA was extracted and used for reverse transcription polymerase chain reaction, quantitative real time-PCR, and in situ hybridisation.
We confirmed the classical descriptions of the vitellogenic process in mosquitoes by verifying that vitellogenin genes are transcribed in the fat bodies of C. quinquefasciatus females. Using RNA in situ hybridisation approach, we showed that vitellogenin genes are also transcribed in developing ovaries, specifically by the follicle cells.
This is the first time that vitellogenin transcripts are observed in mosquito ovaries. Studies to determine if Vg transcripts are translated into proteins and their contribution to the reproductive success of the mosquito need to be further investigated.
库蚊是一种世界性的、与家居有关且高度嗜人血的蚊子，是致病性虫媒病毒（如西尼罗河病毒和裂谷热病毒）以及淋巴丝虫病的传播媒介。目前关于其生殖生理学方面的知识，特别是关于不同组织中卵黄蛋白原表达的知识仍然有限。
在这项研究中，我们分析了库蚊雌性在第一次生殖周期中，脂肪体和卵巢中卵黄蛋白原基因的转录谱。
在第一次生殖周期的不同时间，解剖库蚊的卵巢和/或脂肪体，并提取总 RNA，用于反转录聚合酶链反应、定量实时 PCR 和原位杂交。
我们通过验证卵黄蛋白原基因在库蚊的脂肪体中转录，证实了蚊子卵黄发生过程的经典描述。使用 RNA 原位杂交方法，我们表明卵黄蛋白原基因也在发育中的卵巢中转录，特别是由滤泡细胞转录。
这是首次在蚊子的卵巢中观察到卵黄蛋白原转录物。需要进一步研究确定 Vg 转录物是否被翻译成蛋白质以及它们对蚊子生殖成功的贡献。
