GCN2和mTORC1信号路径对动物机体氨基酸平衡的调节作用

摘要

氨基酸平衡对哺乳动物健康生长具有重要意义,而在维持机体氨基酸平衡的过程中,GCN2和mTORC1信号路径发挥着重要作用.GCN2路径能有效感应胞内氨基酸缺乏,而mTORC1路径则能对胞外氨基酸水平的变化做出响应.本文结合近年来有关GCN2和mTORC1的研究进展,阐述了氨基酸充足和氨基酸饥饿条件下,GCN2和mTORC1这两条信号路径的感应特点以及随后启动的相关应答机制,包括蛋白质合成、拒食行为、氨基酸转运体表达增加、氨基酸合成酶增加和自噬启动等.了解动物在不同的氨基酸营养状态下维持细胞内氨基酸平衡的这些调节机制,有助于人们更好的对动物进行氮营养调控,从而改善肠道健康.%Amino acid (AA) balance is of importance to the health and growth of mammals,and GCN2 and mTORC1 signaling pathways play crucial roles in maintaining AA balance in body.GCN2 signaling pathway can effectively sense intracellular AA starvation,mTORC1 signaling pathway can respond to the change of extracellular AA level.Combining with the recent studies regarding GCN2 and mTORC1,this review summarized characteristics of the GCN2 and mTORC1 signaling pathways and the related response mechanism under the condition of AA starvation and sufficiency,e.g.protein synthesis,refusing to feed,an increase of AA transporter,AA synthase expressions and autophagy initiation,etc..Understanding the regulatory mechanism by which cellular AA balance is kept under different AA nutrition status contributes to the nutritional regulating of nitrogen for animals,thus improving animal gut health.