Balzi E, Choder M, Chen W N, Varshavsky A, Goffeau A
Laboratoire d'Enzymologie, Université Catholique de Louvain, Belgium.
J Biol Chem. 1990 May 5;265(13):7464-71.
Aminoacyl-tRNA-protein transferases (Arg-transferases) catalyze post-translational conjugation of specific amino acids to the amino termini of acceptor proteins. A function of these enzymes in eukaryotes has been shown to involve the conjugation of destabilizing amino acids to the amino termini of short-lived proteins, these reactions being a part of the N-end rule pathway of protein degradation (Gonda, D. K., Bachmair, A., Wünning, I., Tobias, J. W., Lane, W. S., and Varshavsky, A. (1989) J. Biol. Chem. 264, 16700-16712). We have cloned the ATE1 gene of the yeast Saccharomyces cerevisiae which encodes arginyl-tRNA-protein transferase. ATE1 gives rise to a approximately 1.6-kilobase mRNA and codes for a 503-residue protein. Expression of the yeast ATE1 gene in Escherichia coli, which lacks Arg-transferases, was used to show that the ATE1 protein possesses the Arg-transferase activity. Null ate1 mutants are viable but lack the Arg-transferase activity and are unable to degrade those substrates of the N-end rule pathway that start with residues recognized by the Arg-transferase.
氨酰基-tRNA-蛋白质转移酶（精氨酸转移酶）催化特定氨基酸与受体蛋白质氨基末端的翻译后缀合。这些酶在真核生物中的一项功能已被证明涉及将不稳定氨基酸缀合到短命蛋白质的氨基末端，这些反应是蛋白质降解的N端规则途径的一部分（贡达，D.K.，巴赫迈尔，A.，温宁，I.，托拜厄斯，J.W.，莱恩，W.S.，和瓦尔沙夫斯基，A.（1989年）《生物化学杂志》264，16700 - 16712）。我们已经克隆了酿酒酵母的ATE1基因，该基因编码精氨酰-tRNA-蛋白质转移酶。ATE1产生一个约1.6千碱基的mRNA，并编码一个503个残基的蛋白质。在缺乏精氨酸转移酶的大肠杆菌中表达酵母ATE1基因，用于证明ATE1蛋白具有精氨酸转移酶活性。缺失ate1的突变体是可行的，但缺乏精氨酸转移酶活性，并且无法降解那些以精氨酸转移酶识别的残基开头的N端规则途径的底物。
