6EU2

Apo RNA Polymerase III - open conformation (oPOL3)

6EU2 の概要

• エントリーDOI: 10.2210/pdb6eu2/pdb
• EMDBエントリー: 3957
• 分子名称: DNA-directed RNA polymerase III subunit RPC1, DNA-directed RNA polymerases I, II, and III subunit RPABC5, DNA-directed RNA polymerases I and III subunit RPAC2, ... (19 entities in total)
• 機能のキーワード: rna pol iii, promoter opening, transcription
• 由来する生物種: Saccharomyces cerevisiae (strain ATCC 204508 / S288c) (Baker's yeast); 詳細
• タンパク質・核酸の鎖数: 17
• 化学式量合計: 694526.96

構造登録者

Abascal-Palacios, G.,Ramsay, E.P.,Beuron, F.,Morris, E.,Vannini, A. (登録日: 2017-10-27, 公開日: 2018-01-17, 最終更新日: 2024-05-15)

主引用文献

Abascal-Palacios, G.,Ramsay, E.P.,Beuron, F.,Morris, E.,Vannini, A.
Structural basis of RNA polymerase III transcription initiation.
Nature, 553:301-306, 2018

PubMed Abstract: RNA polymerase (Pol) III transcribes essential non-coding RNAs, including the entire pool of transfer RNAs, the 5S ribosomal RNA and the U6 spliceosomal RNA, and is often deregulated in cancer cells. The initiation of gene transcription by Pol III requires the activity of the transcription factor TFIIIB to form a transcriptionally active Pol III preinitiation complex (PIC). Here we present electron microscopy reconstructions of Pol III PICs at 3.4-4.0 Å and a reconstruction of unbound apo-Pol III at 3.1 Å. TFIIIB fully encircles the DNA and restructures Pol III. In particular, binding of the TFIIIB subunit Bdp1 rearranges the Pol III-specific subunits C37 and C34, thereby promoting DNA opening. The unwound DNA directly contacts both sides of the Pol III cleft. Topologically, the Pol III PIC resembles the Pol II PIC, whereas the Pol I PIC is more divergent. The structures presented unravel the molecular mechanisms underlying the first steps of Pol III transcription and also the general conserved mechanisms of gene transcription initiation.

PubMed: 29345637
DOI: 10.1038/nature25441

実験手法

ELECTRON MICROSCOPY (3.4 Å)