A recurrent RNA-binding domain is appended to eukaryotic aminoacyl-tRNA synthetases

AUTOR(ES)
FONTE

Oxford University Press

RESUMO

Aminoacyl-tRNA synthetases of higher eukaryotes possess polypeptide extensions in contrast to their prokaryotic counterparts. These extra domains of poorly understood function are believed to be involved in protein–protein or protein–RNA interactions. Here we showed by gel retardation and filter binding experiments that the repeated units that build the linker region of the bifunctional glutamyl-prolyl-tRNA synthetase had a general RNA-binding capacity. The solution structure of one of these repeated motifs was also solved by NMR spectroscopy. One repeat is built around an antiparallel coiled-coil. Strikingly, the conserved lysine and arginine residues form a basic patch on one side of the structure, presenting a suitable docking surface for nucleic acids. Therefore, this repeated motif may represent a novel type of general RNA-binding domain appended to eukaryotic aminoacyl-tRNA synthetases to serve as a cis-acting tRNA-binding cofactor.

Documentos Relacionados