DIPTERA MEVALONIC ACID METABOLISM AND REGULATION

双翅目甲羟戊酸代谢与调节

• 批准号: 2519035
• 负责人: JOHN A WATSON
• 金额: $ 24.31万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-09-30 至 1998-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2519035
• 关键词: Aedes; Drosophilidae; HMG coA reductases; enzyme activity; fatty acid biosynthesis; fatty acid metabolism; high performance liquid chromatography; messenger RNA; mevalonate; molecular biology; northern blottings; nucleic acid probes; phosphatase inhibitor; phosphoprotein phosphatase; phosphorylation; polyenes

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.

甲羟戊酸（MVA）是代谢必需的唯一前体， 化合物术语“类异戊烯”（例如，泛醌类，多萜醇类， 细胞色素A3、保幼激素、异戊二烯化蛋白质等）。由于许多 类异戊烯不能从饮食来源获得，连续MVA 合成是生命所必需的。MVA合成的调节在 分子水平在真核生物和昆虫中了解甚少 具体来说此外，昆虫不能合成甾醇核， 因此，与类固醇生物相反，它们对MVA的调节 合成仅通过非甾醇类异戊烯的可用性来发出信号。 因此，对昆虫非甾醇的深入了解， 类异戊烯介导的MVA合成调节可能提供独特的 深入了解其他真核生物的这一过程。我们建议使用 永生化双翅目Kc，其次是白纹伊蚊C7-10和伊蚊 埃及ATCC-125细胞）作为模型来定义非甾醇介导的调节 MVA合成 3-羟基-3-甲基戊二酰辅酶A还原酶（HMGR）是一种酶， 催化从HMG-CoA合成MVA。此外，果蝇Kc细胞 HMGR Vmax活性与体内MVA的绝对合成一致 评分员因此，了解非甾醇类异戊烯介导的 Kc细胞HMGR代谢的控制也应该定义 MVA合成。 果蝇HMGR蛋白和mRNA的分子探针将用于 结合详细的放射代谢通量分析来描绘Kc细胞 非固醇介导的MVA合成调节。三个假设将是 解决：（1）非固醇类异戊烯介导的永生化调节 双翅目昆虫细胞HMGR代谢主要是翻译后的。（二） C15，C20-聚戊烯醇和/或C15，C20-聚戊烯醇-1-焦磷酸信号 MVA介导的Kc细胞HMGR的下调，和（3）调节性 类异戊烯通过改变HMGR的表达来调节Kc细胞HMGR的功能。 HMGR和/或辅助蛋白的磷酸化状态。这一努力 将通过使用完整的和穿孔的Kc电池来促进。 拟议的研究将产生新的基本信息， 非固醇类异戊烯介导的Kc细胞MVA合成/HMGR调节 新陈代谢.最后，需要MVA衍生产品用于昆虫 发育、卵子发生和其他。因此， 不同双翅目昆虫的MVA代谢和调控可能揭示了物种 新的化学/生物杀虫剂的具体目标。