Molecular Genetics of Dengue Resistance in Mosquitoes

描述（由申请人提供）：节肢动物传播的病毒性疾病已重新成为大多数热带国家的主要健康问题。登革热的发病率在过去20年中大大增加，包括其出血形式与相关的人类死亡。登革热是全球25亿人的疾病，年发病率估计为5000万至1亿人，登革出血热病例数十万例，每年约有2.4万人死亡。由于疫苗开发缺乏进展、蚊虫媒介对杀虫剂产生抗药性以及有组织的蚊虫控制工作普遍减少，登革热控制工作受到限制。本提案的目标是确定、分离和表征与登革热病毒蚊子媒介能力相关的遗传因素，并利用这些信息制定旨在破坏病原体生命周期的新型登革热疾病控制策略。提出的目标是基于这样一个一般假设，即可以在实验室菌株和地理现场收集的埃及伊蚊中确定一组核心基因，这些基因对暴露于不同登革热血清型有不同的调控。该研究计划采用了Ae的第一批产品之一。埃及伊蚊基因组计划，微板阵列和部分测序的cdna，作为最终完全阐明这些基因关系及其表型结果的门户。概述的实验代表了第一代cDNA微阵列在Ae高通量表达分析中的应用。在登革热病毒攻击后，对差异表达基因进行了详细分析，并将实验室研究获得的信息迅速转化为实地研究。将在特立尼达和海地进行实地研究，因为这两个国家是登革热流行国家，分别有组织的病媒控制规划和有限的病媒控制规划。该项目的具体目的是：1)表征Ae的差异基因表达模式。埃及伊蚊在吸食了受登革热感染的血液后；2)对候选登革热媒介能力基因进行功能分析；3)研究选定的生物和非生物因素对登革热流行地区传播的影响，包括通过微阵列分析鉴定的关键候选登革热媒介能力基因。

DESCRIPTION (provided by the applicant): Arthropod-borne viral disease have re-remerged as major health problems in most tropical countries. The incidence of dengue fever has increased greatly over the pat 20 years, including its hemorrhagic form with associated human fatalities. Dengue is a treat to >2.5 billion people, with a annual incidence estimated at 50-100 million and several hundred thousand cases of DHF with approximately 24,000 death per year. Dengue control efforts have been limited by the lack of progress in vaccine development, development of insecticide resistance in mosquito vectors, and the general decline in organized mosquito control efforts. The objective of this proposal is to identify, isolate and characterize genetic factors associated with mosquito vector competence for dengue virus, with a long-term goal of using this information to develop novel dengue disease control strategies aimed toward disrupting the pathogen life cycle. The proposed objectives are based on the general hypothesis that a core suite of genes that are differentially regulated in response to exposure to different dengue serotypes can be identified among both laboratory strains and geographic field collections of the mosquito, Aedes aegypti. The research plan employs one of the first products of the Ae. aegypti genome project, microplate-arrayed and partially sequenced cDNAs, as a gateway into the eventual complete elucidation of these gene relationships and their phenotypic outcome. The outlined experiments represent the application of first generation cDNA micro-arrays for high-throughput expression analysis in Ae. aegypti following a dengue virus challenge, detailed analysis of differentially expressed genes, and the rapid transition of information gained from laboratory studies into field studies. Field studies will be conducted in Trinidad and Haiti, as they represent dengue endemic countries with organized versus limited vector control programs, respectively. The specific aims of this project are: 1) characterize differential gene expression patterns in Ae. aegypti following a dengue-infected blood meal; 2) conduct functional analysis od candidate dengue vector competence genes; and, 3) investigate the impact of selected biotic and abiotic factors on dengue transmission in endemic areas, including key candidate dengue vector competence genes identified by micro-array analysis.