5LYV

The crystal structure of 7SK 5'-hairpin - Osmium derivative

5LYV の概要

• エントリーDOI: 10.2210/pdb5lyv/pdb
• 分子名称: 7SK RNA, osmium (III) hexammine, MAGNESIUM ION, ... (5 entities in total)
• 機能のキーワード: non-coding rna major groove base triple transcription, rna
• 由来する生物種: Homo sapiens (HUMAN)
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 37007.60

構造登録者

Martinez-Zapien, D.,Legrand, P.,McEwen, A.G.,Pasquali, S.,Dock-Bregeon, A.-C. (登録日: 2016-09-28, 公開日: 2017-01-25, 最終更新日: 2024-02-07)

主引用文献

Martinez-Zapien, D.,Legrand, P.,McEwen, A.G.,Proux, F.,Cragnolini, T.,Pasquali, S.,Dock-Bregeon, A.C.
The crystal structure of the 5 functional domain of the transcription riboregulator 7SK.
Nucleic Acids Res., 45:3568-3579, 2017

PubMed Abstract: In vertebrates, the 7SK RNA forms the scaffold of a complex, which regulates transcription pausing of RNA-polymerase II. By binding to the HEXIM protein, the complex comprising proteins LARP7 and MePCE captures the positive transcription elongation factor P-TEFb and prevents phosphorylation of pausing factors. The HEXIM-binding site embedded in the 5΄-hairpin of 7SK (HP1) encompasses a short signature sequence, a GAUC repeat framed by single-stranded uridines. The present crystal structure of HP1 shows a remarkably straight helical stack involving several unexpected triples formed at a central region. Surprisingly, two uridines of the signature sequence make triple interactions in the major groove of the (GAUC)2. The third uridine is turned outwards or inward, wedging between the other uridines, thus filling the major groove. A molecular dynamics simulation indicates that these two conformations of the signature sequence represent stable alternatives. Analyses of the interaction with the HEXIM protein confirm the importance of the triple interactions at the signature sequence. Altogether, the present structural analysis of 7SK HP1 highlights an original mechanism of swapping bases, which could represent a possible '7SK signature' and provides new insight into the functional importance of the plasticity of RNA.

PubMed: 28082395
DOI: 10.1093/nar/gkw1351

実験手法

X-RAY DIFFRACTION (2.35 Å)