DIPTERA MEVALONIC ACID METABOLISM AND REGULATION

甲伐他酸(MVA)是代谢必需物质的唯一前体 化合物术语为“异戊烯类”(例如，泛醌，二十二碳二烯， 细胞色素A3、保幼激素、早熟蛋白等)。因为有很多人 异戊烯类化合物不能从饮食来源获得，持续的MVA 合成是生命所必需的。植物体内MVA合成的调控 在真核生物和昆虫中，分子水平了解得很少。 具体地说。此外，昆虫不能合成固醇核， 因此，与产生立体结构的微生物相比，它们对MVA的调节 合成仅通过非甾醇异戊烯类化合物的可获得性来表示。 因此，对昆虫非甾醇的确切理解是可能的 异戊烯介导的MVA合成调节可能提供独特的 洞察其他真核生物的这一过程。我们建议使用 永生化的双翅目昆虫KC，其次是白纹伊蚊C7-10和伊蚊 Aegypti ATCC-125细胞)作为定义非甾醇介导的调节的模型 MVA的合成。 3-羟基-3-甲基戊二酰辅酶A还原酶是一种 催化HMG-CoA合成MVA。此外，果蝇KC细胞 HMGR Vmax活性与体内MVA绝对合成一致 评分员。因此，对非甾醇异戊烯类化合物的认识 对KC细胞HMGR代谢的控制也应确定对 MVA合成。 果蝇HMGR蛋白和mRNA的分子探针将用于 用详细的放射代谢通量分析来描绘KC细胞 非固醇对MVA合成的调节作用。三个假设将是 地址：(1)非甾醇异戊烯介导的永生化调节 双翅目昆虫细胞内HMGR的代谢主要是翻译后代谢。(2) C15，C20-聚戊烯醇和/或C15，C20-聚戊烯-1-焦磷酸盐信号 MVA介导的KC细胞HMGR下调，以及(3)调节 异戊烯类化合物通过改变KC细胞HMGR功能调节HMGR功能 HMGR和/或辅助蛋白的磷酸化状态。这一努力 将通过使用完整和穿孔的KC细胞来促进移植。 拟议的研究将产生关于以下方面的新的基本信息 非甾醇异戊烯对KC细胞MVA合成/HMGR的调节作用 新陈代谢。最后，昆虫需要MVA衍生产品。 发育、卵子发生和其他因此，理解 不同双翅目昆虫MVA的代谢和调节可能揭示物种 新的化学/生物杀虫剂的具体目标。

Mevalonic acid (MVA) is the unique precursor for metabolically essential compounds terms "isopentenoids" (e.g., ubiquinones, dolichols, cytochromse a3, juvenile hormones, prenylated proteins, etc.). Since many isopentenoids cannot be obtained from dietary sources, continuous MVA synthesis is required for life. The regulation of MVA synthesis at the molecular level is poorly understood in eukaryotes in general and insects specifically. Moreover, insects cannot synthesize the sterol nucleus, therefore, in contrast to sterologenic organisms, their regulation of MVA synthesis is signaled exclusively by nonsterol isopentenoid availability. Thus, it is possible that a firm understanding of insect nonsterol isopentenoid-mediated regulation of MVA synthesis might provide unique insight into this process in other eukaryotes. We propose to use immortalized Dipteran Kc and secondarily Aedes albopictus C7-10 and Aedes aegypti ATCC-125 cells) as models to define nonsterol-mediated regulation of MVA synthesis. 3-Hydroxy-3-methylglutaryl coenzymeA reductase (HMGR) is the enzyme which catalyzes MVA synthesis from HMG-CoA. In addition, Drosophila Kc cell HMGR Vmax activities are congruent with absolute in vivo MVA synthesis rater. Therefore, an understanding of nonsterol isopentenoid-mediated control of Kc cell HMGR metabolism should also define the regulation of MVA synthesis. Molecular probes for Drosophila HMGR protein and mRNA will be used in conert with detailed radio-metabolic flux analyses to delineate Kc cell nonsterol-mediated regulation of MVA synthesis. Three hypotheses will be addressed: (1) nonsterol isopentenoid-mediated regulation of immortalized Dipteran cellular HMGR metabolism is primarily posttranslational. (2) C15, C20-polyprenols and/or C15, C20-polyprenl-1-pyrophosphates signal MVA-mediated down regulation of Kc cell HMGR, and (3) regulatory isopentenoids modulate Kc cell HMGR function by altering the phosphorylation status of HMGR and/or ancillary proteins. This effort will be facilitated by the use of both intact and perforated Kc cells. The proposed studies will generate new fundamental information about nonsterol isopentenoid-mediated regulation of Kc cell MVA synthesis/HMGR metabolism. Lastly, MVA-derived products are required for insect development, oogenesis, and othe ress Therefore, an understanding of different Dipterans' MVA metabolism and regulation might reveal species specific targets for new chemical/biological insecticides.