7NQ4

Human tRNA guanine transglycosylase (TGT), RNA-bound covalent intermediate

7NQ4 の概要

• エントリーDOI: 10.2210/pdb7nq4/pdb
• 分子名称: Queuine tRNA-ribosyltransferase catalytic subunit 1, Queuine tRNA-ribosyltransferase accessory subunit 2, RNA, ... (6 entities in total)
• 機能のキーワード: trna modification, queuine incorporation, rna complex, heterodimer, rna binding protein
• 由来する生物種: Homo sapiens (Human); 詳細
• タンパク質・核酸の鎖数: 3
• 化学式量合計: 97730.30

構造登録者

Sievers, K.,Ficner, R. (登録日: 2021-03-01, 公開日: 2021-08-11, 最終更新日: 2024-01-31)

主引用文献

Sievers, K.,Welp, L.,Urlaub, H.,Ficner, R.
Structural and functional insights into human tRNA guanine transgylcosylase.
Rna Biol., 18:382-396, 2021

PubMed Abstract: The eukaryotic tRNA guanine transglycosylase (TGT) is an RNA modifying enzyme incorporating queuine, a hypermodified guanine derivative, into the tRNAs. While both subunits of the functional heterodimer have been crystallized individually, much of our understanding of its dimer interface or recognition of a target RNA has been inferred from its more thoroughly studied bacterial homolog. However, since bacterial TGT, by incorporating queuine precursor preQ, deviates not only in function, but as a homodimer, also in its subunit architecture, any inferences regarding the subunit association of the eukaryotic heterodimer or the significance of its unique catalytically inactive subunit are based on unstable footing. Here, we report the crystal structure of human TGT in its heterodimeric form and in complex with a 25-mer stem loop RNA, enabling detailed analysis of its dimer interface and interaction with a minimal substrate RNA. Based on a model of bound tRNA, we addressed a potential functional role of the catalytically inactive subunit QTRT2 by UV-crosslinking and mutagenesis experiments, identifying the two-stranded βEβF-sheet of the QTRT2 subunit as an additional RNA-binding motif.

PubMed: 34241577
DOI: 10.1080/15476286.2021.1950980

実験手法

X-RAY DIFFRACTION (2.88 Å)