Yeast mitochondrial leucyl-tRNA synthetase (LeuRS) binds to the bI4 intron and collaborates with the bI4 maturase to aid excision of the group I intron. Deletion analysis isolated the inserted LeuRS CP1 domain as a critical factor in the protein's splicing activity. Protein fragments comprised of just the LeuRS CP1 region rescued complementation of a yeast strain that expressed a splicing-defective LeuRS. Three-hybrid analysis determined that these CP1-containing LeuRS fragments, ranging from 214 to 375 amino acids, bound to the bI4 intron. In each case, interactions with only the LeuRS protein fragment specifically stimulated bI4 intron splicing activity. Substitution of a homologous CP1 domain from isoleucyl-tRNA synthetase or mutation within the LeuRS CP1 region of the smallest protein fragment abolished RNA binding and splicing activity. The CP1 domain is best known for its amino acid editing activity. However, these results suggest that elements within the LeuRS CP1 domain also play a novel role, independent of the full-length tRNA synthetase, in binding the bI4 group I intron and facilitating its self-splicing activity.
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http://dx.doi.org/10.1093/emboj/cdf671 | DOI Listing |
J Mol Graph Model
September 2018
Institute of Molecular Biology and Genetics, National Academy of Sciences of Ukraine, 150 Academician Zabolotny Str., 03680 Kyiv, Ukraine.
The accuracy of protein synthesis is provided by the editing functions of aminoacyl-tRNA synthetases (aaRSs), a mechanism that eliminates misactivated amino acids or mischarged tRNAs. Despite research efforts, some molecular bases of these mechanisms are still unclear. The post-transfer editing pathway of leucyl-tRNA synthetase (LeuRS) carried out in a special insertion domain (the Connective Polypeptide 1 or CP1), as editing domain.
View Article and Find Full Text PDFJ Biol Chem
October 2015
From the State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, the Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai and the School of Life Science and Technology, ShanghaiTech University, 319 Yue Yang Road, Shanghai 200031, China
The connective polypeptide 1 (CP1) editing domain of leucyl-tRNA synthetase (LeuRS) from various species either harbors a conserved active site to exclude tRNA mis-charging with noncognate amino acids or is evolutionarily truncated or lost because there is no requirement for high translational fidelity. However, human mitochondrial LeuRS (hmtLeuRS) contains a full-length but degenerate CP1 domain that has mutations in some residues important for post-transfer editing. The significance of such an inactive CP1 domain and a translational accuracy mechanism with different noncognate amino acids are not completely understood.
View Article and Find Full Text PDFACS Chem Biol
October 2015
European Molecular Biology Laboratory, Grenoble Outstation and Unit of Virus Host-Cell Interactions, UJF-EMBL-CNRS, UMI 3265 , 71 Avenue des Martyrs, BP181, 38042 Grenoble Cedex 9, France.
A new class of antimicrobial benzoxaborole compounds was identified as a potent inhibitor of leucyl-tRNA synthetase (LeuRS) and therefore of protein synthesis. In a novel mechanism, AN2690 (5-fluoro-1,3-dihydro-1-hydroxy-2,1-benzoxaborole) blocks fungal cytoplasmic LeuRS by covalently trapping tRNA(Leu) in the editing site of the enzyme's CP1 domain. However, some resistant mutation sites are located outside of the CP1 hydrolytic editing active site.
View Article and Find Full Text PDFRNA
September 2014
Center for RNA Research, State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, The Chinese Academy of Sciences, Shanghai 200031, China School of Life Science and Technology, ShanghaiTech University, Shanghai 200031, China.
Nucleic Acids Res
May 2013
State Key Laboratory of Molecular Biology, Center for RNA Research, Institute of Biochemistry and Cell Biology, the Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, PR China.
The leucine-specific domain (LSD) is a compact well-ordered module that participates in positioning of the conserved KMSKS catalytic loop in most leucyl-tRNA synthetases (LeuRSs). However, the LeuRS from Mycoplasma mobile (MmLeuRS) has a tetrapeptide GKDG instead of the LSD. Here, we show that the tetrapeptide GKDG can confer tRNA charging and post-transfer editing activity when transplanted into an inactive Escherichia coli LeuRS (EcLeuRS) that has had its LSD deleted.
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