Simos G, Sauer A, Fasiolo F, Hurt E C
Biochemie-Zentrum Heidelberg, University of Heidelberg, Germany.
Mol Cell. 1998 Jan;1(2):235-42. doi: 10.1016/s1097-2765(00)80024-6.
Two yeast enzymes that catalyze aminoacylation of tRNAs, MetRS and GluRS, form a complex with the protein Arc1p. We show here that association of Arc1p with MetRS and GluRS is required in vivo for effective recruitment of the corresponding cognate tRNAs within this complex. Arc1p is linked to MetRS and GluRS through its amino-terminal domain, while its middle and carboxy-terminal parts comprise a novel tRNA-binding domain. This results in high affinity binding of cognate tRNAs and increased aminoacylation efficiency. These findings suggest that Arc1p operates as a mobile, trans-acting tRNA-binding synthetase domain and provide new insight into the role of eukaryotic multimeric synthetase complexes.
两种催化tRNA氨基酰化的酵母酶，即甲硫氨酸-tRNA合成酶（MetRS）和谷氨酸-tRNA合成酶（GluRS），与蛋白质Arc1p形成复合物。我们在此表明，Arc1p与MetRS和GluRS的结合在体内是该复合物有效募集相应同源tRNA所必需的。Arc1p通过其氨基末端结构域与MetRS和GluRS相连，而其中间和羧基末端部分构成一个新的tRNA结合结构域。这导致同源tRNA的高亲和力结合并提高了氨基酰化效率。这些发现表明，Arc1p作为一个可移动的、反式作用的tRNA结合合成酶结构域发挥作用，并为真核多聚体合成酶复合物的作用提供了新的见解。
