《生命科学》 2012, 24(6): 511-517

亮氨酰-tRNA合成酶通过细胞内的亮氨酸调节雷帕霉素受体复合物(TORC1)活性的新功能

谭　敏，王恩多^*

(中国科学院上海生命科学研究院生物化学与细胞生物学研究所，分子生物学国家重点实验室，RNA研究中心，上海 200031)

摘　要：摘　要：TORC1 (target of rapamycin complex 1)可整合营养、能量、生长因子及氨基酸等多种细胞外信号，调控基因转录、蛋白质翻译、核糖体合成等生物过程，在细胞生长和凋亡中发挥极为重要的作用。亮氨酰-tRNA合成酶(LeuRS)的经典功能是催化合成亮氨酰-tRNA直接参与遗传信息的解码合成蛋白质。最新研究结果表明人细胞质LeuRS除了经典功能外，还参与调控TORC1途径。综述了LeuRS的非经典功能，它是如何通过感受细胞内的亮氨酸浓度来调节TORC1活性的。这些结果表明了古老的氨基酰-tRNA合成酶家族在进化的过程中被赋予了新的功能。
关键词：亮氨酰-tRNA 合成酶；非经典功能；雷帕霉素受体复合物1(TORC1)；亮氨酸

Noncanonical function of leucyl-tRNA synthetase — regulating TORC1-signaling pathway through sensing intracellular leucine

TAN Min， WANG En-Duo^*

(Center for RNA Research， State Key Laboratory of Molecular Biology， Institute of Biochemistry and Cell Biology， Shanghai Institutes for Biological Sciences， Chinese Academy of Sciences， Shanghai 200031， China)

Abstract: Abstract: TORC1 regulates translation and cell growth in response to a variety of signals， including hormones， growth factors， energy levels， and amino acids such as leucine. The dysregulation of TORC1 pathway is associated with several hamartoma syndromes and cancers. Leucyl-tRNA synthetase (LeuRS) catalyzes the formation of Leu-tRNA for decoding the genetic information. Recent works reveal that the pathway for leucine signaling to TORC1 is mediated by LeuRS， which functions as a sensor for intracellular leucine. These results show that an old family of aminoacyl-tRNA synthetases is conferred new function during the evolution.
Key words: leucyl-tRNA synthetases; noncanonical function; TORC1; leucine