Kasai Shinji, Komagata Osamu, Tomita Takashi, Sawabe Kyoko, Tsuda Yoshio, Kurahashi Hiromu, Ishikawa Takeshi, Motoki Mitsugu, Takahashi Tomoya, Tanikawa Tsutomu, Yoshida Masahiro, Shinjo Goro, Hashimoto Tomoyuki, Higa Yukiko, Kobayashi Mutsuo
Department of Medical Entomology, National Institute of Infectious Diseases, Tokyo 162-8640, Japan.
Jpn J Infect Dis. 2008 May;61(3):184-91.
The Culex pipiens complex consists of vector mosquitoes that transmit important human pathogens. In this study we established a simplified method to distinguish three members of the Cx. pipiens complex, Cx. p. pallens Coquillet, Cx. p. form molestus Forskal, and Cx. quinquefasciatus Say, collected in Japan. Sequence analysis of the Drosophila Ace-orthologous acetylcholinesterase (Ace) gene (668 to 680 bp) revealed that a single polymorphic region characterizes each species. Based on this region, specific primers that distinguish Cx. p. form molestus (ACEpip2) and Cx. p. pallens (ACEpall2) were newly designed. Polymerase chain reactions were performed with the genomic DNA of Culex mosquitoes as the template, and these primers clearly distinguished two Culex spp. The accuracy of the designed primers was evaluated with 38 colonies of mosquito samples collected from 9 prefectures of Japan. The testing revealed that the distribution of anautogenous Cx. p. pipiens has not been confirmed in Japan. It also revealed that the male of Cx. p. pallens possesses an Ace gene haplotype that is highly similar to the sequence of Cx. quinquefasciatus. This improved method allows the evaluation of vector competence of Cx. p.molestus, which is the suspected vector of West Nile virus.
致倦库蚊复合体由传播重要人类病原体的媒介蚊虫组成。在本研究中，我们建立了一种简化方法来区分在日本采集的致倦库蚊复合体的三个成员，即淡色库蚊指名亚种、骚扰库蚊致倦亚种和致倦库蚊。对果蝇Ace直系同源乙酰胆碱酯酶（Ace）基因（668至680 bp）进行序列分析发现，每个物种都有一个单一的多态性区域。基于该区域，新设计了区分骚扰库蚊致倦亚种（ACEpip2）和淡色库蚊指名亚种（ACEpall2）的特异性引物。以库蚊基因组DNA为模板进行聚合酶链反应，这些引物能够清晰地区分两种库蚊。用从日本9个县采集的38个蚊群样本评估了所设计引物的准确性。测试结果表明，在日本尚未证实非嗜血性淡色库蚊的分布。研究还发现，淡色库蚊指名亚种的雄性拥有一种与致倦库蚊序列高度相似的Ace基因单倍型。这种改进方法能够评估西尼罗河病毒疑似媒介骚扰库蚊致倦亚种的媒介能力。
