View source for 6gwk


==The crystal structure of Hfq from Caulobacter crescentus==
<StructureSection load='6gwk' size='340' side='right'caption='[[6gwk]], [[Resolution|resolution]] 2.15&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6gwk]] is a 24 chain structure with sequence from [https://en.wikipedia.org/wiki/Cauvc Cauvc]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6GWK OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=6GWK FirstGlance]. <br>
</td></tr><tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">hfq, CC_1745 ([https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=190650 CAUVC])</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=6gwk FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6gwk OCA], [https://pdbe.org/6gwk PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=6gwk RCSB], [https://www.ebi.ac.uk/pdbsum/6gwk PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=6gwk ProSAT]</span></td></tr>
</table>
== Function ==
[[https://www.uniprot.org/uniprot/HFQ_CAUVC HFQ_CAUVC]] RNA chaperone that binds small regulatory RNA (sRNAs) and mRNAs to facilitate mRNA translational regulation in response to envelope stress, environmental stress and changes in metabolite concentrations. Also binds with high specificity to tRNAs. 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
We have solved the X-ray crystal structure of the RNA chaperone protein Hfq from the alpha-proteobacterium Caulobacter crescentus to 2.15-A resolution, resolving the conserved core of the protein and the entire C-terminal domain (CTD). The structure reveals that the CTD of neighboring hexamers pack in crystal contacts, and that the acidic residues at the C-terminal tip of the protein interact with positive residues on the rim of Hfq, as has been recently proposed for a mechanism of modulating RNA binding. De novo computational models predict a similar docking of the acidic tip residues against the core of Hfq. We also show that C. crescentus Hfq has sRNA binding and RNA annealing activities and is capable of facilitating the annealing of certain Escherichia coli sRNA:mRNA pairs in vivo. Finally, we describe how the Hfq CTD and its acidic tip residues provide a mechanism to modulate annealing activity and substrate specificity in various bacteria.

Caulobacter crescentus Hfq structure reveals a conserved mechanism of RNA annealing regulation.,Santiago-Frangos A, Frohlich KS, Jeliazkov JR, Malecka EM, Marino G, Gray JJ, Luisi BF, Woodson SA, Hardwick SW Proc Natl Acad Sci U S A. 2019 May 10. pii: 1814428116. doi:, 10.1073/pnas.1814428116. PMID:31076551<ref>PMID:31076551</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 6gwk" style="background-color:#fffaf0;"></div>

==See Also==
*[[Protein Hfq|Protein Hfq]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Cauvc]]
[[Category: Large Structures]]
[[Category: Frohlich, K S]]
[[Category: Gray, J R]]
[[Category: Hardwick, S W]]
[[Category: Jeliazkov, J R]]
[[Category: Luisi, B F]]
[[Category: Santiago-Frangos, A]]
[[Category: Woodson, S A]]
[[Category: Caulobacter]]
[[Category: Hfq]]
[[Category: Natively unstructured protein]]
[[Category: Rna binding protein]]
[[Category: Rna-protein interaction]]
[[Category: Srna]]