Biosynthesis of Linoleic Acid in Insects

脊椎动物不能合成，因此需要饮食 亚油酸的来源，18：2（n-6），既用作 膜结构组分和作为膜的前体 生理上重要的类花生酸。 直到最近， 曾被认为是昆虫， 脊椎动物不能合成亚油酸。 研究表明，一些，但不是全部，昆虫 物种具有δ-12去饱和酶，因此能够 产生亚油酸。 该提案旨在审查 这种合成亚油酸的蟑螂， 美洲蚜、蚜虫、豌豆蚜和蟋蟀， 刺水蚤 重点将放在旨在 明确排除微生物的贡献， 共生和外部，亚油酸合成，即。的 正是昆虫的组织 将油酸酯去饱和为亚油酸酯。 此外，形式 δ-12去饱和酶的底物的量，以及 亚油酸的伸长和去饱和作用将是 考察 这些研究将描述独特的过程 某些昆虫通过这种方式获得了 不依赖于多不饱和脂肪酸的饮食要求 脂肪酸 重要的基础知识 从这项工作中将获得比较脂质代谢。 亚油酸是脊椎动物的必需脂肪酸。 它 是一种重要的膜组分， 对于调节许多细胞的类蛋白质， 功能协调发展的 脊椎动物缺乏合成能力 亚油酸和满足他们的饮食需求， 消费的植物，其中，除了原生动物和 真菌容易合成脂肪酸。 直到最近， 昆虫和其他动物一样， 合成亚油酸。 最近的证据表明， 昆虫有这种能力。 本研究将探讨 这种现象。 它将提供一个基本的了解， 昆虫亚油酸生物合成及其前景 对利用昆虫特有的 激素调节途径作为害虫控制的手段。

Vertebrates cannot synthesize and thus require a dietary source of linoleic acid, 18:2(n-6), which is used both as a structural component of membranes and as precursor for physiologically important eicosanoids. Until recently, it had been thought that insects, as is the case for vertebrates, were unable to synthesize linoleic acid. Studies have demonstrated that some, but not all, insect species possess a delta-12 desaturase and are thus able to produce linoleic acid. This proposal is designed to examine this synthesis of linoleic acid in the cockroach, Periplaneta americana, the aphid, Acyrthosiphon pisum, and the cricket, Acheta domesticus. Emphasis will be on studies designed to unambiguously rule out the contribution of microorganisms, both symbiotic and exterior, to linoleate synthesis, ie. that it is the insect tissue that is responsible for the desaturation of oleate to linoleate. In addition, the form of the substrate for the delta-12 desaturase and the further elongation and desaturation of linoleic acid will be examined. These studies will characterize the unique process by which certain insect species have gained a nutritional independence from dietary requirements for polyunsaturated fatty acids. Significant fundamental knowledge of comparative lipid metabolism will be obtained from this work. Linoleic acid is an essential fatty acid for vertebrates. It is an important membrane component and serves as a precursor for hormone-like substances that regulate many cell functions. Vertebrates lack the ability to synthesize linoleic acid and fulfill their dietary requirement by the consumption of plants, which, in addition to protozoa and fungi readily synthesize the fatty acid. Until recently, it was thought that insects, like other animals, were unable to synthesize linoleic acid. Recent evidence now suggests that insects do have this capability. This research will examine this phenomenon. It will provide a basic understanding of linoleic acid biosynthesis in insects and may have future implications for the exploitation of the insect-specific pathways of hormone regulation as a means of pest control.