MOLECULAR STUDY OF INSECT VECTOR ANTIHEMOSTATIC FACTORS

在以脊椎动物为食的过程中，食血昆虫遇到 宿主止血反应的成分，特别是 血管收缩和形成血小板堵塞。因此， 食血昆虫的唾液成分中含有血小板 抗聚集活性(Apyrase)，许多产生唾液 血管扩张剂。这些成分也可能影响寄生虫的进程。 通过修改摄食部位的宿主免疫反应来建立。 尽管它们很重要，但人们对它们的分子生物学知之甚少 这些物质。 我建议在分子水平上比较apyrase和血管扩张 在两种独立进化出觅血功能的昆虫中使用的药物，以及 是重要的疾病媒介：黄热病蚊子埃及伊蚊 和三甲虫Rhodnius prolixus。具体地说，该项目 涉及： (1)快速原激肽原基因克隆的分离和测序 被加工成在Ae中释放血管扩张性速激肽。埃及伊蚊。 (2)三个非结合血红素基因克隆的分离和测序 蛋白质，这些蛋白质在异丙醇中起血管扩张剂的作用。 (3)Rhodnius apyrase基因克隆的分离和测序 与伊蚊apyrase的比较； (4)以这些克隆为探针，研究apyrase的调控。 两种昆虫中的血管扩张剂； (5)利用血红素蛋白克隆生产重组野生型和 定点突变蛋白，研究其结构/功能 可逆NO结合的关系和生物物理学；以及 (6)分离和测序包括罗得牛在内的基因组克隆 血红素蛋白基因，研究其基因组织和调控 一组功能独特的蛋白质。 最终，这项研究将使我们能够更详细地了解 与早期阶段有关的生化和药理学事件 通过食血昆虫传播寄生虫。两者的比较 具有独立进化的吸血能力的物种将指出 同余，这可能是各种媒介昆虫共同的。

In the course of feeding from vertebrates, blood feeding insects encounter components of their host's hemostatic responses, especially vasoconstriction and formation of a platelet plug. Consequently, hematophagous insects have salivary components with platelet antiaggregating activity (apyrase), and many produce salivary vasodilators. These components may also influence the course of parasite establishment by modifying the host immune response at the feeding site. Despite their importance, little is known of the molecular biology of these substances. I propose to compare, at the molecular level, apyrase and vasodilatory agents in two insects that have independently evolved blood feeding, and are significant disease vectors: the yellow fever mosquito Aedes aegypti and the triatomine bug Rhodnius prolixus. Specifically, the project involves: (1) isolating and sequencing cDNA clones for the preprotachykinin, which is processed to release vasodilatory tachykinins in Ae. aegypti. (2) isolating and sequencing cDNA clones for three NO.binding heme proteins, which function as vasodilators in A. prolixus. (3) isolating and sequencing cDNA clones for the Rhodnius apyrase, for comparison with the Aedes apyrase; (4) using these clones as probes to study regulation of the apyrase and vasodilators in both insects; (5) using the heme protein clones to produce recombinant wild-type and site-specific mutant proteins, to study the structure/function relationships and biophysics of reversible NO binding; and (6) isolating and sequencing genomic clones which include the Rhodnius heme protein genes, to study gene organization and regulation of this functionally unique group of proteins. Ultimately, this research will permit a more detailed knowledge of the biochemical and pharmacological events associated with the earliest stages of parasite transmission by blood-feeding insects. Comparison of two species, which have independently evolved blood feeding, will point to congruencies which may be common to a variety of vector insects.