Structural basis for shape-selective recognition and aminoacylation of a D-armless human mitochondrial tRNA.

ABSTRACT: Human mitochondrial gene expression relies on the specific recognition and aminoacylation of mitochondrial tRNAs (mtRNAs) by nuclear-encoded mitochondrial aminoacyl-tRNA synthetases (mt-aaRSs). Despite their essential role in cellular energy homeostasis, strong mutation pressure and genetic drift have led to an unparalleled sequence erosion of animal mtRNAs. The structural and functional consequences of this erosion are not understood. Here, we present cryo-EM structures of the human mitochondrial seryl-tRNA synthetase (mSerRS) in complex with mtRNA^Ser(GCU). These structures reveal a unique mechanism of substrate recognition and aminoacylation. The mtRNA^Ser(GCU) is highly degenerated, having lost the entire D-arm, tertiary core, and stable L-shaped fold that define ca

SUBMITTER: Kuhle B 

PROVIDER: S-EPMC9427863 | biostudies-literature | 2022 Aug

REPOSITORIES: biostudies-literature