Collaborative Research: The Molecular Identification and Action of Bursicon, the Insect Cuticle Sclerotizing Hormone

在昆虫蜕皮(蜕皮)过程中，一种名为法士康的昆虫荷尔蒙对新皮肤(角质层)的硬化是必不可少的。滑囊虫的定时释放和行动对所有昆虫的生存至关重要，很可能对所有节肢动物也是如此。虽然在1935年发现了法斯康，并已知它是一种多肽，但其分子结构尚未确定，仍然是昆虫神经内分泌学中一个尚未解决的重大问题。霍尼格实验室已经提纯了这种激素，并从一些昆虫中获得了法氏囊的部分氨基酸序列。最近，他们能够使用这些序列来识别果蝇基因组中的一个特定基因序列，CG13419。该合作项目的主要目的是确定CG13419基因产物是否为功能性法氏囊激素，这是了解法氏囊的作用的重要一步。基因在真核细胞中的表达和在果蝇中的过度表达的分子技术将与使用相关苍蝇(Sarcophaga)的“连接苍蝇”生物检测相结合，以测试法氏囊的活性。如果显示了生物活性的法氏囊，该序列将用于在蛾子Manduca中进行cdna筛选，这是一个研究得很好的昆虫系统，在其中调节蜕皮的复杂激素相互作用已经被阐明。重组蛋白和来自保守序列的合成肽将产生新的抗体来识别大脑中的神经分泌细胞，并阐明Manduca中滑囊素释放的时间和空间激活。这项工作的结果将为理解大脑和内分泌系统如何共同协调导致周期性角质层硬化的多个生化事件提供潜在的突破。对这种关键激素的了解可能会为农业在开发虫害防治和管理甲壳类水产养殖方面提供新的战略。此外，这两个机构之间的合作包括多学科博士后培训。

An insect hormone called bursicon is essential for hardening of the new skin (cuticle) after the insect has shed its old one during molting (ecdysis). The timed release and actions of bursicon are critically important for the survival of all insects and, most likely, all arthropods. Although bursicon was discovered in 1935 and is known to be a peptide, its molecular structure has not been established, and remains a major unsolved problem in insect neuroendocrinology. The Honegger lab has purified the hormone and obtained partial amino acid sequences for bursicon from some insects. Recently they were able to use these sequences to identify a particular gene sequence, CG13419, in the genome of the fruitfly Drosophila. The primary aim of this collaborative project is to determine whether the CG13419 gene product is the functional bursicon hormone, as an important step to understanding the actions of bursicon. Molecular techniques for gene expression in eukaryotic cells and overexpression in Drosophila will be combined with the 'ligated fly' bioassay using the related blowfly (Sarcophaga) to test for bursicon activity. If bioactive bursicon is shown, the sequence will be used for cDNA screening in the moth Manduca, a well-studied insect system in which the complex hormonal interactions regulating ecdysis have been illuminated. From the recombinant proteins and synthesized peptides from conserved sequence stretches, new antibodies will be produced to identify neurosecretory cells in the brain, and to clarify the temporal and spatial activation of bursicon release in Manduca. Results from this work will provide a potential breakthrough for understanding how the brain and endocrine systems together orchestrate multiple biochemical events leading to periodic cuticular hardening. Knowledge about this key hormone may provide novel strategies for agriculture in developing insect pest controls, and in managing crustacean aquaculture. In addition, this collaboration between two institutions includes multi-disciplinary postdoctoral training.