View source for 4ym7


==RNA polymerase I structure with an alternative dimer hinge==
<StructureSection load='4ym7' size='340' side='right'caption='[[4ym7]], [[Resolution|resolution]] 5.50&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4ym7]] is a 60 chain structure with sequence from [https://en.wikipedia.org/wiki/Saccharomyces_cerevisiae Saccharomyces cerevisiae]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4YM7 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4YM7 FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 5.5&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=4ym7 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4ym7 OCA], [https://pdbe.org/4ym7 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4ym7 RCSB], [https://www.ebi.ac.uk/pdbsum/4ym7 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4ym7 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/RPA1_YEAST RPA1_YEAST] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Largest and catalytic core component of RNA polymerase I which synthesizes ribosomal RNA precursors. Forms the polymerase active center together with the second largest subunit. A single stranded DNA template strand of the promoter is positioned within the central active site cleft of Pol I. A bridging helix emanates from RPA1 and crosses the cleft near the catalytic site and is thought to promote translocation of Pol I by acting as a ratchet that moves the RNA-DNA hybrid through the active site by switching from straight to bent conformations at each step of nucleotide addition (By similarity).
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
RNA polymerase I (Pol I) is the central, 14-subunit enzyme that synthesizes the ribosomal RNA (rRNA) precursor in eukaryotic cells. The recent crystal structure of Pol I at 2.8 A resolution revealed two novel elements: the `expander' in the active-centre cleft and the `connector' that mediates Pol I dimerization [Engel et al. (2013), Nature (London), 502, 650-655]. Here, a Pol I structure in an alternative crystal form that was solved by molecular replacement using the original atomic Pol I structure is reported. The resulting alternative structure lacks the expander but still shows an expanded active-centre cleft. The neighbouring Pol I monomers form a homodimer with a relative orientation distinct from that observed previously, establishing the connector as a hinge between Pol I monomers.

An alternative RNA polymerase I structure reveals a dimer hinge.,Kostrewa D, Kuhn CD, Engel C, Cramer P Acta Crystallogr D Biol Crystallogr. 2015 Sep 1;71(Pt 9):1850-5. doi:, 10.1107/S1399004715012651. Epub 2015 Aug 25. PMID:26327374<ref>PMID:26327374</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4ym7" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Saccharomyces cerevisiae]]
[[Category: Cramer P]]
[[Category: Engel C]]
[[Category: Kostrewa D]]
[[Category: Kuhn C-D]]