Structural highlights
Function
[THG1_YEAST] Adds a GMP to the 5'-end of tRNA(His) after transcription and RNase P cleavage.[1]
Publication Abstract from PubMed
tRNA maturation involves several steps, including processing, splicing, CCA addition, and posttranscriptional modifications. tRNAHis guanylyltransferase (Thg1) is the only enzyme known to catalyze templated nucleotide addition in the 3'-5' direction, unlike other DNA and RNA polymerases. For a better understanding of its unique catalytic mechanism at the molecular level, we determined the crystal structure of GTP-bound Thg1 from Saccharomyces cerevisiae at the maximum resolution of 3.0 A. The structure revealed the enzyme to have a tetrameric conformation that is well conserved among different species, and the GTP molecule was clearly bound at the active site, coordinating with two magnesium ions. In addition, two flexible protomers at the potential binding site (PBS) for tRNAHis were observed. We suggest that the PBS of the tetramer could also be one of the sites for interaction with partner proteins.
Crystal structure of tRNAHis guanylyltransferase from Saccharomyces cerevisiae.,Lee K, Lee EH, Son J, Hwang KY Biochem Biophys Res Commun. 2017 Aug 19;490(2):400-405. doi:, 10.1016/j.bbrc.2017.06.054. Epub 2017 Jun 13. PMID:28623126[2]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Gu W, Jackman JE, Lohan AJ, Gray MW, Phizicky EM. tRNAHis maturation: an essential yeast protein catalyzes addition of a guanine nucleotide to the 5' end of tRNAHis. Genes Dev. 2003 Dec 1;17(23):2889-901. Epub 2003 Nov 21. PMID:14633974 doi:http://dx.doi.org/10.1101/gad.1148603
- ↑ Lee K, Lee EH, Son J, Hwang KY. Crystal structure of tRNAHis guanylyltransferase from Saccharomyces cerevisiae. Biochem Biophys Res Commun. 2017 Aug 19;490(2):400-405. doi:, 10.1016/j.bbrc.2017.06.054. Epub 2017 Jun 13. PMID:28623126 doi:http://dx.doi.org/10.1016/j.bbrc.2017.06.054