View source for 8h3v


==Cryo-EM structure of the full transcription activation complex NtcA-NtcB-TAC==
<StructureSection load='8h3v' size='340' side='right'caption='[[8h3v]], [[Resolution|resolution]] 4.50&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[8h3v]] is a 15 chain structure with sequence from [https://en.wikipedia.org/wiki/Anabaena Anabaena]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=8H3V OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=8H3V FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Electron Microscopy, [[Resolution|Resolution]] 4.5&#8491;</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=8h3v FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=8h3v OCA], [https://pdbe.org/8h3v PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=8h3v RCSB], [https://www.ebi.ac.uk/pdbsum/8h3v PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=8h3v ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/RPOB_NOSS1 RPOB_NOSS1] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates.[HAMAP-Rule:MF_01321]
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== Publication Abstract from PubMed ==
Transcription factors respond to multilevel stimuli and co-occupy promoter regions of target genes to activate RNA polymerase (RNAP) in a cooperative manner. To decipher the molecular mechanism, here we report two cryo-electron microscopy structures of Anabaena transcription activation complexes (TACs): NtcA-TAC composed of RNAP holoenzyme, promoter and a global activator NtcA, and NtcA-NtcB-TAC comprising an extra context-specific regulator, NtcB. Structural analysis showed that NtcA binding makes the promoter DNA bend by approximately 50 degrees , which facilitates RNAP to contact NtcB at the distal upstream NtcB box. The sequential binding of NtcA and NtcB induces looping back of promoter DNA towards RNAP, enabling the assembly of a fully activated TAC bound with two activators. Together with biochemical assays, we propose a 'DNA looping' mechanism of cooperative transcription activation in bacteria.

DNA looping mediates cooperative transcription activation.,Han SJ, Jiang YL, You LL, Shen LQ, Wu X, Yang F, Cui N, Kong WW, Sun H, Zhou K, Meng HC, Chen ZP, Chen Y, Zhang Y, Zhou CZ Nat Struct Mol Biol. 2024 Feb;31(2):293-299. doi: 10.1038/s41594-023-01149-7. , Epub 2024 Jan 4. PMID:38177666<ref>PMID:38177666</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 8h3v" style="background-color:#fffaf0;"></div>

==See Also==
*[[RNA polymerase 3D structures|RNA polymerase 3D structures]]
*[[Sigma factor 3D structures|Sigma factor 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Anabaena]]
[[Category: Large Structures]]
[[Category: Chen ZP]]
[[Category: Han SJ]]
[[Category: Jiang YL]]
[[Category: Kong WW]]
[[Category: Shen LQ]]
[[Category: Wu XX]]
[[Category: Yang F]]
[[Category: You LL]]
[[Category: Zhang Y]]
[[Category: Zhou CZ]]