title: Interaction of eukaryotic threonyl-tRNA synthetase with high-Mr RNAs and tRNA(Thr).
abstract: Threonyl-tRNA synthetase of rabbit reticulocytes was purified to homogeneity. We have found that this enzyme can interact not only with cognate tRNA(Thr), but also with high-Mr RNAs. tRNA(Thr) removes rRNA from the complexes with threonyl-tRNA synthetase. On the other hand, rRNA is unable to dissociate tRNA(Thr) from the complexes with the enzyme. Despite its dimeric organization, threonyl-tRNA synthetase is unable to form stable ternary complexes with tRNA(Thr) and rRNA. In the extract of rabbit reticulocytes about one-third of the threonyl-tRNA synthetase molecules are in association with cognate tRNA(Thr) and thus are unable to interact with high-Mr RNAs.
mesh_terms: D000327:Adsorption; D000604:Amino Acyl-tRNA Synthetases / Q000378:metabolism*; D000818:Animals; D001667:Binding, Competitive; D002845:Chromatography; D004591:Electrophoresis, Polyacrylamide Gel; D007118:Immunoassay; D008970:Molecular Weight; D012313:RNA / Q000378:metabolism*; D012335:RNA, Ribosomal / Q000378:metabolism; D012346:RNA, Transfer, Amino Acyl / Q000378:metabolism*; D011817:Rabbits; D012156:Reticulocytes / Q000201:enzymology; D013379:Substrate Specificity; D013914:Threonine-tRNA Ligase / Q000378:metabolism*
chemical_list: D012335:RNA, Ribosomal; D012346:RNA, Transfer, Amino Acyl; D012313:RNA; D000604:Amino Acyl-tRNA Synthetases; D013914:Threonine-tRNA Ligase