In Bombyx mori, two dorsolateral neurosecretory cells (NSCs) in each of the two brain lobes have been identified as prothoracicotropic hormone (PTTH) producing cells. This neuropeptide in insects stimulates the prothoracic gland for the synthesis and release of ecdysone, responsible for the molting events. Allatotropin (AT) and allatostatin (AST) are allatoregulatory neuropeptides that regulate juvenile hormone biosynthesis. Here, using by RT-qPCR, we showed that in B. mori, nutritional stress modulates the mRNA expression of AT and AST-C (allatostain type C) in the central nervous system consisting of the brain lobes and all the associated ganglia. Using whole-mount in situ hybridization, we showed that the feeding status of Bombyx larvae also influences the expression of PTTH in the NSCs of the brain. Food deprivation significantly decreased the mRNA expression levels of PTTH in larvae at active or terminal growth period. Further, we showed that insulin modulates the expression level of PTTH. However, its action was dependent on the feeding status of the larvae. At feeding, the insulin decreased the PTTH expression level, while at food deprivation, the insulin increased the PTTH expression level. The data thus indicates that larval feeding status plays an important role in altering the mRNA expression levels of allatoregulatory peptide genes and PTTH. This article is protected by copyright. All rights reserved.

中文翻译：

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幼虫摄食状态调节家蚕 PTTH 和同种异体调节肽编码基因的转录水平

在家蚕中，两个脑叶中的每个脑叶中的两个背外侧神经分泌细胞 (NSC) 已被鉴定为促胸腺激素 (PTTH) 产生细胞。昆虫中的这种神经肽刺激前胸腺合成和释放蜕皮激素，负责蜕皮事件。Allatotropin (AT) 和 allatostatin (AST) 是调节保幼激素生物合成的异源调节神经肽。在这里，我们通过 RT-qPCR 显示，在桑蚕中，营养应激调节了由脑叶和所有相关神经节组成的中枢神经系统中 AT 和 AST-C（Allatostain C 型）的 mRNA 表达。使用整体原位杂交，我们发现家蚕幼虫的摄食状态也会影响大脑神经干细胞中 PTTH 的表达。食物剥夺显着降低了处于活跃期或末期的幼虫体内PTTH mRNA的表达水平。此外，我们发现胰岛素调节 PTTH 的表达水平。然而，它的作用取决于幼虫的摄食状态。在进食时，胰岛素降低 PTTH 表达水平，而在食物剥夺时，胰岛素增加 PTTH 表达水平。因此，数据表明幼虫摄食状态在改变异源调节肽基因和 PTTH 的 mRNA 表达水平方面起着重要作用。本文受版权保护。版权所有。胰岛素降低 PTTH 表达水平，而在食物剥夺时，胰岛素增加 PTTH 表达水平。因此，数据表明幼虫摄食状态在改变异源调节肽基因和 PTTH 的 mRNA 表达水平方面起着重要作用。本文受版权保护。版权所有。胰岛素降低 PTTH 表达水平，而在食物剥夺时，胰岛素增加 PTTH 表达水平。因此，数据表明幼虫摄食状态在改变异源调节肽基因和 PTTH 的 mRNA 表达水平方面起着重要作用。本文受版权保护。版权所有。