6EU3
Apo RNA Polymerase III - closed conformation (cPOL3)
Summary for 6EU3
| Entry DOI | 10.2210/pdb6eu3/pdb |
| EMDB information | 3958 |
| Descriptor | 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) |
| Functional Keywords | rna pol iii, promoter opening, transcription |
| Biological source | Saccharomyces cerevisiae (strain ATCC 204508 / S288c) (Baker's yeast) More |
| Total number of polymer chains | 17 |
| Total formula weight | 694526.96 |
| Authors | Abascal-Palacios, G.,Ramsay, E.P.,Beuron, F.,Morris, E.,Vannini, A. (deposition date: 2017-10-27, release date: 2018-01-17, Last modification date: 2024-05-15) |
| Primary citation | 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 Cited by 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: 29345637DOI: 10.1038/nature25441 PDB entries with the same primary citation |
| Experimental method | ELECTRON MICROSCOPY (3.3 Å) |
Structure validation
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