View source for 7cv1


==Structure of human tRNAHis guanylyltransferase (Thg1) in the presence of human mitochondrial tRNAHis==
<StructureSection load='7cv1' size='340' side='right'caption='[[7cv1]], [[Resolution|resolution]] 4.00&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[7cv1]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=7CV1 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=7CV1 FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 4&#8491;</td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=7cv1 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=7cv1 OCA], [https://pdbe.org/7cv1 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=7cv1 RCSB], [https://www.ebi.ac.uk/pdbsum/7cv1 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=7cv1 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/THG1_HUMAN THG1_HUMAN] Adds a GMP to the 5'-end of tRNA(His) after transcription and RNase P cleavage. This step is essential for proper recognition of the tRNA and for the fidelity of protein synthesis.<ref>PMID:21059936</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Human tRNA(His) guanylyltransferase (HsThg1) catalyzes the 3'-5' addition of guanosine triphosphate (GTP) to the 5'-end (-1 position) of tRNA(His), producing mature tRNA(His) In human cells, cytoplasmic and mitochondrial tRNA(His) has adenine (A) or cytidine (C), respectively, opposite to G-1 Little attention has been paid to the structural requirements of incoming GTP in 3'-5' nucleotidyl addition by HsThg1. In this study, we evaluated the incorporation efficiencies of various GTP analogs by HsThg1, and compared the reaction mechanism with that of Candida albicans Thg1 (CaThg1). HsThg1 incorporated GTP opposite A or C in the template most efficiently. In contrast to CaThg1, HsThg1 could incorporate UTP opposite A, and guanosine diphosphate (GDP) opposite C. These results suggest that HsThg1 could transfer not only GTP, but also other NTPs, by forming Watson-Crick (WC) hydrogen bonds between the incoming NTP and the template base. On the basis of the molecular mechanism, HsThg1 succeeded in labeling the 5'-end of tRNA(His) with biotinylated GTP. Structural analysis of HsThg1 was also performed in the presence of the mitochondrial tRNA(His) Structural comparison of HsThg1 with other Thg1 family enzymes suggested that the structural diversity of the C-terminal domain of the Thg1 enzymes might be involved in the formation of WC base pairing between the incoming GTP and template base. These findings provide new insights into an unidentified biological function of HsThg1 and also into the applicability of HsThg1 to the 5'-terminal modification of RNAs.

Analysis of GTP addition in the reverse (3'-5') direction by human tRNA(His) guanylyltransferase.,Nakamura A, Wang D, Komatsu Y RNA. 2021 Mar 23. pii: rna.078287.120. doi: 10.1261/rna.078287.120. PMID:33758037<ref>PMID:33758037</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 7cv1" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Komatsu Y]]
[[Category: Nakamura A]]
[[Category: Wang D]]