© 2007 Oxford University Press
Aminoacyl-tRNA surveillance by EF-Tu in mammalian mitochondria.
Department of Chemistry and Biotechnology, School of Engineering, The University of Tokyo 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
Abstract
Aminoacyl-tRNA synthetases specifically recognize their cognate tRNAs and ensure the accuracy of translation. However, in mammalian mitochondria, seryl-tRNA synthetase (mt SerRS) significantly misacylates tRNAGln, indicating the presence of another mechanism to be required to maintain the fidelity of mitochondrial protein synthesis. We have revealed that mammalian mitochondrial elongation factor Tu (mt EF-Tu) tends to interact with seryl-tRNAGln with lower affinity than glutaminyl-tRNAGln and seryl-tRNASer. This result proposes that mt EF-Tu has a critical role to maintain the translational fidelity by surveillance of aminoacyl-tRNAs for quality control.