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3ung

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Revision as of 16:57, 11 August 2016

Structure of the Cmr2 subunit of the CRISPR RNA silencing complex

Structural highlights

3ung is a 1 chain structure with sequence from Pyrfu. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:	, ,
Related:	3ur3
Gene:	PF1129 (PYRFU)
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[CMR2_PYRFU] CRISPR (clustered regularly interspaced short palindromic repeat), is an adaptive immune system that provides protection against mobile genetic elements (viruses, transposable elements and conjugative plasmids). CRISPR clusters contain sequences complementary to antecedent mobile elements and target invading nucleic acids. CRISPR clusters are transcribed and processed into CRISPR RNA (crRNA), formerly called psiRNA (prokaryotic silencing) in this organism. Part of the Cmr ribonucleoprotein complex which has divalent cation-dependent endoribonuclease activity specific for ssRNA complementary to the crRNA, generating 5' hydroxy- and 3' phosphate or 2'-3' cyclic phosphate termini. It is not known which subunit has endoribonuclease activity. Cmr complex does not cleave ssDNA complementary to the crRNA. Cleavage of invading RNA is guided by the crRNA; substrate cleavage occurs a fixed distance (14 nt) from the 3' end of the crRNA. In vitro reconstitution shows Cmr1-2 and Cmr5 are not necessary for cleavage. Probably not the subunit that cleaves pre-crRNA, as mutation of numerous metal-binding residues have no effect on cleavage by assembled complex.^[1]

Publication Abstract from PubMed

Cmr2 is the largest and an essential subunit of a CRISPR RNA-Cas protein complex (the Cmr complex) that cleaves foreign RNA to protect prokaryotes from invading genetic elements. Cmr2 is thought to be the catalytic subunit of the effector complex because of its N-terminal HD nuclease domain. Here, however, we report that the HD domain of Cmr2 is not required for cleavage by the complex in vitro. The 2.3A crystal structure of Pyrococcus furiosus Cmr2 (lacking the HD domain) reveals two adenylyl cyclase-like and two alpha-helical domains. The adenylyl cyclase-like domains are arranged as in homodimeric adenylyl cyclases and bind ADP and divalent metals. However, mutagenesis studies show that the metal- and ADP-coordinating residues of Cmr2 are also not critical for cleavage by the complex. Our findings suggest that another component provides the catalytic function and that the essential role by Cmr2 does not require the identified ADP- or metal-binding or HD domains in vitro.

Structure of the Cmr2 Subunit of the CRISPR-Cas RNA Silencing Complex.,Cocozaki AI, Ramia NF, Shao Y, Hale CR, Terns RM, Terns MP, Li H Structure. 2012 Mar 7;20(3):545-53. PMID:22405013^[2]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Hale CR, Zhao P, Olson S, Duff MO, Graveley BR, Wells L, Terns RM, Terns MP. RNA-guided RNA cleavage by a CRISPR RNA-Cas protein complex. Cell. 2009 Nov 25;139(5):945-56. doi: 10.1016/j.cell.2009.07.040. PMID:19945378 doi:10.1016/j.cell.2009.07.040
↑ Cocozaki AI, Ramia NF, Shao Y, Hale CR, Terns RM, Terns MP, Li H. Structure of the Cmr2 Subunit of the CRISPR-Cas RNA Silencing Complex. Structure. 2012 Mar 7;20(3):545-53. PMID:22405013 doi:10.1016/j.str.2012.01.018

1 Structural highlights
2 Function
3 Publication Abstract from PubMed
4 See Also
5 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/3ung"

@@ Line 1: / Line 1: @@
 ==Structure of the Cmr2 subunit of the CRISPR RNA silencing complex==
 <StructureSection load='3ung' size='340' side='right' caption='[[3ung]], [[Resolution|resolution]] 2.31&Aring;' scene=''>
@@ Line 6: / Line 7: @@
 <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[3ur3|3ur3]]</td></tr>
 <tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">PF1129 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=186497 PYRFU])</td></tr>
-<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3ung FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3ung OCA], [http://www.rcsb.org/pdb/explore.do?structureId=3ung RCSB], [http://www.ebi.ac.uk/pdbsum/3ung PDBsum]</span></td></tr>
+<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3ung FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3ung OCA], [http://pdbe.org/3ung PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=3ung RCSB], [http://www.ebi.ac.uk/pdbsum/3ung PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=3ung ProSAT]</span></td></tr>
 </table>
 == Function ==
@@ Line 18: / Line 19: @@
 From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
 </div>
+<div class="pdbe-citations 3ung" style="background-color:#fffaf0;"></div>
 ==See Also==

3ung

From Proteopedia

Revision as of 16:57, 11 August 2016

Structure of the Cmr2 subunit of the CRISPR RNA silencing complex

Structural highlights

Function

Publication Abstract from PubMed

See Also

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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