ANOPHELES STEPHENSI NO SYNTHASE--IMPACT ON PLASMODIUM

脊椎动物一氧化氮合酶（NOS）亚型催化一氧化氮（NO） 产生神经元信号，血管舒张和破坏 病原体，包括疟原虫属的肝侵入子孢子，的 疟疾的病原体。 这个实验室的最新结果表明 斯氏按蚊是疟原虫的天然载体， 基因（AsNOS）与最近描述的果蝇具有惊人的同源性 NOS基因。 逆转录聚合酶链反应检测表明 AsNOS在恶性疟原虫和伯氏疟原虫感染期间合成， 这表明阿诺啡林蚊子可能具有类似的一氧化氮杀伤作用， 疟原虫的机制 已为《公约》提出了两个目标， AsNOS鉴定：（1）克隆、测序和酶活性分析 的AsNOS，和（2）证明NO毒性蚊子阶段的疟原虫， 体外和体内。 全长AsNOS和相关上游的序列 区域将确认AsNOS的身份， 的表达，并有助于构建表达系统， 酶分析 AsNOS在体外催化NO的产生将证实 其行为为NOS同种型。 AsNOS的体外特性 确认其作为NOS同种型的行为。 AsNOS及其活性的研究进展 活动将为蚊子寄生虫生物学提供新的见解， 研究其他昆虫媒介中NOS的工具，也许 为设计抗疟原虫蚊子提供了新的基础， 阻断人类疟疾寄生虫的传播

Vertebrate nitric oxide synthase (NOS) isoforms catalyze nitric oxide (NO) production for neuronal signalling, vasodilation, and destruction of pathogens, including liver-invading sporozoites of Plasmodium spp., the causative agents of malaria. Recent results from this laboratory indicate that Anopheles stephensi, a natural vector of Plasmodium, possesses a NOS gene (AsNOS) with striking homology to the recently described Drosophila NOS gene. Reverse transcriptase-polymerase chain reaction assays indicate that AsNOS is synthesized during P. falciparum and P. berghei infections, suggesting that anorpheline mosquitoes may possess an analogous NO killing mechanism for Plasmodium. Two objectives have been proposed for the characterization of AsNOS: (1) clone, sequence, and analyze enzyme activity of AsNOS, and (2) demonstrate NO toxicity to mosquito stage Plasmodium in vitro and in vivo. Sequence of full-length AsNOS and associated upstream regions will confirm the identity of AsNOS, provide insight into regulation of its expression, and facilitate construction of an expression system for enzyme analysis. Catalysis of NO production by AsNOS in vitro will confirm its behavior as a NOS isoform. Characterization of AsNOS in vitro will confirm its behavior as a NOS isoform. Characterization of AsNOS and its activity will provide new insights into mosquito-parasite biology, provide tools with which to examine NOS in other insect vectors, and perhaps provide a novel basis for engineering Plasmodium-refractory mosquitoes to interrupt the transmission of human malaria parasites.