Neuropeptide Control of Ecdysone Biosynthesis

Gilbert 9300164吉尔伯特博士的研究是关于昆虫Manduca sexta大脑中的一种激素作用于专门的腺体(前胸腺)，使这些腺体开始合成一种特定的类固醇激素，即蜕皮激素的机制。蜕皮类固醇是导致昆虫蜕皮的荷尔蒙。即脱下外骨骼，这样它就可以生长。它们还会引起变态，即毛毛虫转化为蛹，然后转化为成虫或蝴蝶的方式。大脑神经激素的合成和释放是光周期等环境信号的结果，如果昆虫要生存和成功，前胸腺合成和释放蜕皮类固醇的过程必须极其精确。他正在研究这种多肽激素与腺体相互作用的方法，即刺激化合物的合成，第二信使反过来间接介导控制蜕皮类固醇生成的特定蛋白质的磷酸化(添加磷酸基团)。通过利用由单层同质细胞组成的前胸腺，他最终应该能够深入了解多肽激素诱导类固醇生成的机制，这是更多异质性肾上腺所不可能做到的。***

Gilbert 9300164 The studies by Dr. Gilbert on the mechanism by which a hormone from the brain of the insect Manduca sexta acts upon specialized glands (prothoracic glands) to cause these glands to begin synthesizing a specific steroid hormone, an ecdysteroid. Ecdysteroids are hormones that cause the insect to molt. i.e. shed its exoskeleton, so that it can grow. They also elicit metamorphosis, i.e. the means by which a caterpillar is transformed into a pupa and then into an adult moth or butterfly. The brain neurohormone is synthesized and released as a result of environmental cues such as photoperiod and the synthesis and release of Ecdysteroids by the prothoracic glands must be extremely precise if the insect is to survive and be successful. He is studying the means by which this peptide hormone interacts with the glands, i.e. to stimulate the synthesis of a compound, a second messenger, which in turn indirectly mediates the phosphorylation (addition of a phosphate group) of specific proteins that control ecdysteroidogenesis. By utilizing the prothoracic glands which are composed of a single layer of homogeneous cells, he should ultimately gain insights into the mechanism of peptide hormone induced steroidogenesis that would not be possible with the more heterogeneous adrenal gland. ***