MOLECULAR PHYSIOLOGY OF THE EPITRACHEAL ENDOCRINE SYSTEM

气管外内分泌系统的分子生理学

• 批准号: 2667775
• 负责人: MICHAEL E ADAMS
• 金额: $ 24.4万
• 依托单位: UNIVERSITY OF CALIFORNIA RIVERSIDE
• 依托单位国家: 美国
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-03-01 至 2002-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2667775
• 关键词: Aedes; Drosophilidae; Manduca; bioassay; biological signal transduction; central nervous system; complementary DNA; cyclic AMP; cyclic GMP; endocrine gland /system; gene expression; genetic library; high performance liquid chromatography; hormone biosynthesis; hormone receptor; hormone regulation /control mechanism; juvenile hormones; mass spectrometry; molecular cloning; molting; neuroendocrine system; polymerase chain reaction

Insect development from larva to adult depends on the repeated shedding of old cuticle via a highly stereotyped behavior called ecdysis. We recently identified a novel, segmentally distributed endocrine system of epitracheal glands (EG) in Manduca sexta that produce "ecdysis- triggering hormone" (ETH). Our preliminary data suggests that the brain peptide eclosion hormone, formerly thought to act on the nervous system, actually triggers ETH release from the EG. Released ETH provides an immediate chemical signal for ecdysis through its direct action on the central nervous system. Additional peptides associated with ETH (ETH-APs) and FMRFamide-like peptides (FLP) also are produced by the EG during the intermolt period and probably are required for the full expression of ecdysis behavior. The discovery of the epitracheal glands and ETH requires a re-definition of the endocrine basis of ecdysis in insects. The objectives of the proposal are to elucidate the regulatory mechanisms controlling the release of EG hormones and to define their functional roles in the orchestration of ecdysis, a complex behavioral process that is critical in the life history of insects. The first objective will be to isolate and obtain amino acid sequences for ETH-like peptides and FLPs. These sequences will be used for production of specific antisera and isolation of their cDNA precursors and genes. The second objective will be elucidate the mechanisms governing expression of release of ETHs and FLPs from the EG. The roles of ecdysteroids and juvenile hormone in regulation of ETH and FLP expression in the EG as well as the sensitivity of EGs to eclosion hormone and/or other potential releasing factors will be examined. The signal transduction steps involved in eclosion hormone-induced release of ETH and FLP from the EGs will be evaluated. The third objective will be to evaluate the signaling pathways underlying ETH action on the nervous system and to identify the ETH receptor. The long range goals of this proposal are to describe the molecular and physiological bases for ecdysis behavior in insects. The simplicity of the EG system, composed of glands containing only 1-3 cells, provides an excellent model for examination of endocrine function at the cellular, developmental, and molecular levels. Since ecdysis is crucial for successful development of insects and other arthropods, understanding the regulatory mechanisms which underlie these precisely timed and synchronized processes may help in the biological control of pest insects and possibly other arthropods.

昆虫从幼虫到成虫的发育取决于反复脱落 通过一种称为蜕皮的高度刻板行为来去除旧角质层。我们 最近发现了一种新型的、分段分布的内分泌系统 Manduca sexta 的气管上腺 (EG) 产生“蜕皮- 触发激素”（ETH）。我们的初步数据表明大脑 肽羽化激素，以前被认为作用于神经 系统，实际上触发了 EG 中的 ETH 释放。释放以太坊 通过其直接提供蜕皮的即时化学信号 对中枢神经系统的作用。其他相关肽 还生产了 ETH (ETH-AP) 和 FMRFamide 样肽 (FLP) 由 EG 在蜕皮间期间进行，并且可能是 充分表达蜕皮行为。气管上的发现 腺体和 ETH 需要重新定义内分泌基础 昆虫的蜕皮。该提案的目标是阐明 控制 EG 激素释放的调节机制 定义它们在蜕皮协调中的功能角色， 在生命史中至关重要的复杂行为过程 昆虫。 第一个目标是分离和获得氨基酸序列 用于类 ETH 肽和 FLP。这些序列将用于 特异性抗血清的生产及其 cDNA 前体的分离 和基因。第二个目标是阐明机制 控制 EG 中 ETH 和 FLP 释放的表达。角色 蜕皮类固醇和保幼激素在 ETH 和 FLP 调节中的作用 EG 中的表达以及 EG 对羽化的敏感性 将检查激素和/或其他潜在的释放因子。这 羽化激素诱导释放涉及的信号转导步骤 来自 EG 的 ETH 和 FLP 将受到评估。第三个目标将 评估 ETH 作用的信号通路 神经系统并识别 ETH 受体。 该提案的长期目标是描述分子和 昆虫蜕皮行为的生理基础。简单性 EG 系统由仅含 1-3 个细胞的腺体组成，提供 用于检查内分泌功能的优秀模型 细胞、发育和分子水平。由于蜕皮至关重要 昆虫和其他节肢动物的成功发育， 准确理解这些背后的监管机制 定时和同步的过程可能有助于生物控制 害虫和可能的其他节肢动物。