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.

甲酸甲酸（MVA）是代谢必不可少的独特前体 化合物术语“等肾上腺素”（例如，泛素酮，dolichols， 细胞色素A3，青少年激素，预元蛋白等）。自从很多 等类固醇无法从饮食来源获得连续MVA 综合是生命所必需的。 MVA合成在 总体而言，在真核生物和昆虫中，分子水平鲜为人知 具体来说。此外，昆虫不能合成固醇核， 因此，与sterologyenic生物相反，它们的MVA调节 合成仅由异苯二酚的可用性仅发出信号。 因此，有可能对昆虫非蛋白醇的坚定理解 等原类样介导的MVA合成调节可能会提供独特的 在其他真核生物中洞悉此过程。我们建议使用 永生的双翅目KC，其次是Aledes balboptus c7-10和艾德斯 Aegypti ATCC-125细胞）作为定义非固醇介导的调节的模型 MVA合成。 3-羟基-3-甲基戊二酰辅酶还原酶（HMGR）是该酶，是该酶 从HMG-COA催化MVA合成。另外，果蝇KC细胞 HMGR VMAX活动与绝对体内MVA合成是一致的 评估者。因此，了解非等类固醇介导的 KC细胞HMGR代谢的控制也应定义 MVA合成。 果蝇HMGR蛋白和mRNA的分子探针将用于 与详细的射电代谢通量分析一起划定KC细胞 非蛋白酶介导的MVA合成调节。三个假设将是 发表：（1）非肾上腺素介导的永生化调节 双翅目细胞HMGR代谢主要是翻译后。 （2） C15，C20-聚丙醇和/或C15，C20-PolyPrenl-1-磷酸酯信号 MVA介导的KC细胞HMGR调节和（3）调节 等类固醇通过改变KC细胞HMGR功能 HMGR和/或辅助蛋白的磷酸化状态。这项努力 使用完整和穿孔的KC细胞将促进。 拟议的研究将生成有关有关的新基本信息 非脊髓类介导的KC细胞MVA合成/HMGR的调节 代谢。最后，昆虫需要MVA衍生的产品 因此，开发，卵子发生和Othe ress对 不同的双胞胎的MVA代谢和调节可能会揭示物种 新的化学/生物杀虫剂的特定靶标。