期刊
RNA BIOLOGY
卷 18, 期 -, 页码 382-396出版社
TAYLOR & FRANCIS INC
DOI: 10.1080/15476286.2021.1950980
关键词
Queuine; tRNA modification; RNA-binding protein; transglycosylase; heterodimer; eukaryotic; structural biology; X-ray crystallography
资金
- DFG [SPP1784, SFB860, EXC 2067/1-390729940]
- Open Access Publication Funds of the Gottingen University
This study reports the crystal structure of human TGT in its heterodimeric form and in complex with a 25-mer stem loop RNA, revealing detailed analysis of its dimer interface and interaction with a minimal substrate RNA. Through experiments and mutagenesis, the two-stranded beta E beta F-sheet of the QTRT2 subunit is identified as an important RNA-binding motif in the catalytically inactive subunit.
The eukaryotic tRNA guanine transglycosylase (TGT) is an RNA modifying enzyme incorporating queuine, a hypermodified guanine derivative, into the tRNAs(Asp,Asn,His,Tyr). 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(1), 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 beta E beta F-sheet of the QTRT2 subunit as an additional RNA-binding motif.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据