Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Qingdao 266237, China.
Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Qingdao 266237, China.
Cell Rep. 2023 Jun 27;42(6):112644. doi: 10.1016/j.celrep.2023.112644. Epub 2023 Jun 12.
Amino acid metabolism is regulated according to nutrient conditions; however, the mechanism is not fully understood. Using the holometabolous insect cotton bollworm (Helicoverpa armigera) as a model, we report that hemolymph metabolites are greatly changed from the feeding larvae to the wandering larvae and to pupae. Arginine, alpha-ketoglutarate (α-KG), and glutamate (Glu) are identified as marker metabolites of feeding larvae, wandering larvae, and pupae, respectively. Arginine level is decreased by 20-hydroxyecdysone (20E) regulation via repression of argininosuccinate synthetase (Ass) expression and upregulation of arginase (Arg) expression during metamorphosis. α-KG is transformed from Glu by glutamate dehydrogenase (GDH) in larval midgut, which is repressed by 20E. The α-KG is then transformed to Glu by GDH-like in pupal fat body, which is upregulated by 20E. Thus, 20E reprogrammed amino acid metabolism during metamorphosis by regulating gene expression in a stage- and tissue-specific manner to support insect metamorphic development.
氨基酸代谢根据营养状况进行调节；然而，其机制尚未完全了解。我们以完全变态昆虫棉铃虫（Helicoverpa armigera）为模型，报告了血淋巴代谢物从取食幼虫到游走幼虫再到蛹的巨大变化。精氨酸、α-酮戊二酸（α-KG）和谷氨酸（Glu）分别被鉴定为取食幼虫、游走幼虫和蛹的标志物代谢物。在变态过程中，20-羟基蜕皮酮（20E）通过抑制精氨酸合成酶（Ass）的表达和上调精氨酸酶（Arg）的表达来调节精氨酸水平，使其降低 20%。α-KG 由幼虫中肠的谷氨酸脱氢酶（GDH）从 Glu 转化而来，而 20E 则抑制其转化。然后，α-KG 由蛹脂肪体中的 GDH-like 转化为 Glu，而 20E 则上调其表达。因此，20E 通过以阶段和组织特异性的方式调节基因表达来重新编程氨基酸代谢，以支持昆虫变态发育。
