熱帶家蚊和地下家蚊幼蟲生長環境對其生長發育及雌蟲生殖之影響

The effect of larval environments on the development and female reproduction in Culex quinquefasciatus & Culex pipiens molestus

黃開國(Kai-Kuo Huang)

指導教授 ： 黃榮南

國立臺灣大學/生物資源暨農學院/昆蟲學研究所/碩士(2012年)

https://doi.org/10.6342/NTU.2012.01156

摘要

蚊子可因生殖營養週期需要血液攝食與否而分為自生型與非自生型兩種，在雌蚊的生殖營養週期，最重要的階段為卵黃蛋白合成時期，當中又以卵黃蛋白原 (vitellogenin, Vg )基因為該時期最主要且有最高表現量的關鍵基因，為了要瞭解自生型與非自生型的Vg基因表現之異同，嘗試以熱帶家蚊（Culex quinquefasciatus）與其相似卻具自生型特性之地下家蚊 (Culex pipiens molestus)作為研究材料，分析兩品種之間的Vg基因表現的模式。同時也針對蚊幼蟲生長條件的控制及生長調節藥劑 （tebufenozide）處理，探討是否能影響其成蟲生殖策略的改變，使其從非自生型轉變成自生型蚊種。結果顯示，提高幼蟲飼養的營養、降低幼蟲飼養密度，以及調整飼養光照條件，確實能增加蛹體體積，以及增大成蟲體型，但仍無法改變其生殖型式。而以 RT-PCR技術偵測蚊子的兩種Vg基因表現，結果顯示無論是地下家蚊或熱帶家蚊，其VgC1和VgC2在幼蟲及蛹期都有少量表現，但在血液攝取後及產卵前，VgC1和VgC2會有明顯的大量表現，產卵後表現量即大副降低，回復到吸血前的少量表現。然而在VgC1大量表現時期，其cDNA會有部分序列被刪除 (delete)，這個現象是否與其生殖機制調節有關，有待進一步深入研究。

關鍵字

熱帶家蚊 ； 地下家蚊 ； 自生型 ； 非自生型 ； 卵黃蛋白原

並列摘要

Autogenous Culex pipiens molestus is a good model for better understanding the relationship between oviposition and non-blood feeding signal. Vitellogenesis is the central step which involves the synthesis and secretion of yolk protein precursors (YPP) on a massive scale by the fat body in mosquito reproduction. In this thesis, the influence of larval rearing environment and Tebufenozide treatment on the growth of mosquito were compared by using two different mosquito species, autogenous (Cx. pipiens molestus) and anautogenous (Culex quinquefasciatus). Subsequently, RT-PCR analysis of Vg mRNA extracted from Cx. quinquefasciatus and Cx. pipiens molestus mosquito during a reproductive cycle will be presented. The results showed that tebufenozide treatment, abounding larval nourishment and low larval intensity have significantly impacted on the growth character and fecundity in both mosquitoes. However, rearing environment and Tebufenozide treatment have no effect on the anautogenous of mosquito. Moreover, vitellogenin genes (VgC1, VgC2) were only highly expressed after a bloodmeal. However, VgC1 sequence showed a 61 bp deletion during the period of high expression The effect of VgC1 sequence deletion on the reproduction of these two mosquitoes is currently unknow and deserves further investigation.

並列關鍵字

Culex quinquefasciatus ； Culex pipiens molestus ； Autogenous ； Anautogenous ； vitellogenin

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