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| | <SX load='5vlz' size='340' side='right' viewer='molstar' caption='[[5vlz]], [[Resolution|resolution]] 4.40Å' scene=''> | | <SX load='5vlz' size='340' side='right' viewer='molstar' caption='[[5vlz]], [[Resolution|resolution]] 4.40Å' scene=''> |
| | == Structural highlights == | | == Structural highlights == |
| - | <table><tr><td colspan='2'>[[5vlz]] is a 181 chain structure with sequence from [http://en.wikipedia.org/wiki/Allolevivirus_subgroup_iii Allolevivirus subgroup iii]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5VLZ OCA]. For a <b>guided tour on the structure components</b> use [http://proteopedia.org/fgij/fg.htm?mol=5VLZ FirstGlance]. <br> | + | <table><tr><td colspan='2'>[[5vlz]] is a 181 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_virus_Qbeta Escherichia virus Qbeta]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5VLZ OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=5VLZ FirstGlance]. <br> |
| - | </td></tr><tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[5vly|5vly]], [[5vm7|5vm7]]</td></tr> | + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Electron Microscopy, [[Resolution|Resolution]] 4.4Å</td></tr> |
| - | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://proteopedia.org/fgij/fg.htm?mol=5vlz FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5vlz OCA], [http://pdbe.org/5vlz PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=5vlz RCSB], [http://www.ebi.ac.uk/pdbsum/5vlz PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=5vlz ProSAT]</span></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=5vlz FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5vlz OCA], [https://pdbe.org/5vlz PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=5vlz RCSB], [https://www.ebi.ac.uk/pdbsum/5vlz PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=5vlz ProSAT]</span></td></tr> |
| | </table> | | </table> |
| | == Function == | | == Function == |
| - | [[http://www.uniprot.org/uniprot/CAPSD_BPQBE CAPSD_BPQBE]] Capsid protein self-assembles to form an icosahedral capsid with a T=3 symmetry, about 26 nm in diameter, and consisting of 89 capsid proteins dimers (178 capsid proteins) (PubMed:27671640, PubMed:19913556). Involved in viral genome encapsidation through the interaction between a capsid protein dimer and the multiple packaging signals present in the RNA genome (PubMed:8943226, PubMed:27671640). Binding of the capsid proteins to the viral RNA induces a conformational change required for efficient T=3 shell formation (PubMed:19913556). The capsid contains also 1 copy of the A2 maturation protein (PubMed:27671640).<ref>PMID:19913556</ref> <ref>PMID:27671640</ref> <ref>PMID:8943226</ref> Acts as a translational repressor of viral replicase synthesis late in infection. This latter function is the result of capsid protein interaction with an RNA hairpin which contains the replicase ribosome-binding site.<ref>PMID:8943226</ref> [[http://www.uniprot.org/uniprot/MATA2_BPQBE MATA2_BPQBE]] Induces host cell lysis (PubMed:11892805). Inhibits host MurA activity thereby blocking the synthesis of murein precursors necessary for the host cell wall biosynthesis (PubMed:11423662). May be responsible for the attachment to the host pilus. Makes extensive contacts with the viral genome (PubMed:28111107).<ref>PMID:11423662</ref> <ref>PMID:11892805</ref> <ref>PMID:23329676</ref> <ref>PMID:28111107</ref> | + | [https://www.uniprot.org/uniprot/CAPSD_BPQBE CAPSD_BPQBE] Capsid protein self-assembles to form an icosahedral capsid with a T=3 symmetry, about 26 nm in diameter, and consisting of 89 capsid proteins dimers (178 capsid proteins) (PubMed:27671640, PubMed:19913556). Involved in viral genome encapsidation through the interaction between a capsid protein dimer and the multiple packaging signals present in the RNA genome (PubMed:8943226, PubMed:27671640). Binding of the capsid proteins to the viral RNA induces a conformational change required for efficient T=3 shell formation (PubMed:19913556). The capsid contains also 1 copy of the A2 maturation protein (PubMed:27671640).<ref>PMID:19913556</ref> <ref>PMID:27671640</ref> <ref>PMID:8943226</ref> Acts as a translational repressor of viral replicase synthesis late in infection. This latter function is the result of capsid protein interaction with an RNA hairpin which contains the replicase ribosome-binding site.<ref>PMID:8943226</ref> |
| - | <div style="background-color:#fffaf0;">
| + | |
| - | == Publication Abstract from PubMed ==
| + | |
| - | In single-stranded RNA bacteriophages (ssRNA phages) a single copy of the maturation protein binds the genomic RNA (gRNA) and is required for attachment of the phage to the host pilus. For the canonical Allolevivirus Qbeta the maturation protein, A2, has an additional role as the lysis protein, by its ability to bind and inhibit MurA, which is involved in peptidoglycan biosynthesis. Here, we determined structures of Qbeta virions, virus-like particles, and the Qbeta-MurA complex using single-particle cryoelectron microscopy, at 4.7-A, 3.3-A, and 6.1-A resolutions, respectively. We identified the outer surface of the beta-region in A2 as the MurA-binding interface. Moreover, the pattern of MurA mutations that block Qbeta lysis and the conformational changes of MurA that facilitate A2 binding were found to be due to the intimate fit between A2 and the region encompassing the closed catalytic cleft of substrate-liganded MurA. Additionally, by comparing the Qbeta virion with Qbeta virus-like particles that lack a maturation protein, we observed a structural rearrangement in the capsid coat proteins that is required to package the viral gRNA in its dominant conformation. Unexpectedly, we found a coat protein dimer sequestered in the interior of the virion. This coat protein dimer binds to the gRNA and interacts with the buried alpha-region of A2, suggesting that it is sequestered during the early stage of capsid formation to promote the gRNA condensation required for genome packaging. These internalized coat proteins are the most asymmetrically arranged major capsid proteins yet observed in virus structures.
| + | |
| - | | + | |
| - | Structures of Qbeta virions, virus-like particles, and the Qbeta-MurA complex reveal internal coat proteins and the mechanism of host lysis.,Cui Z, Gorzelnik KV, Chang JY, Langlais C, Jakana J, Young R, Zhang J Proc Natl Acad Sci U S A. 2017 Oct 31;114(44):11697-11702. doi:, 10.1073/pnas.1707102114. Epub 2017 Oct 16. PMID:29078304<ref>PMID:29078304</ref>
| + | |
| - | | + | |
| - | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br>
| + | |
| - | </div>
| + | |
| - | <div class="pdbe-citations 5vlz" style="background-color:#fffaf0;"></div>
| + | |
| | == References == | | == References == |
| | <references/> | | <references/> |
| | __TOC__ | | __TOC__ |
| | </SX> | | </SX> |
| - | [[Category: Allolevivirus subgroup iii]] | + | [[Category: Escherichia virus Qbeta]] |
| | [[Category: Large Structures]] | | [[Category: Large Structures]] |
| - | [[Category: Cui, Z]] | + | [[Category: Cui Z]] |
| - | [[Category: Zhang, J]] | + | [[Category: Zhang J]] |
| - | [[Category: Phage]]
| + | |
| - | [[Category: Qbeta]]
| + | |
| - | [[Category: Ssrna]]
| + | |
| - | [[Category: Virus]]
| + | |
| Structural highlights
Function
CAPSD_BPQBE Capsid protein self-assembles to form an icosahedral capsid with a T=3 symmetry, about 26 nm in diameter, and consisting of 89 capsid proteins dimers (178 capsid proteins) (PubMed:27671640, PubMed:19913556). Involved in viral genome encapsidation through the interaction between a capsid protein dimer and the multiple packaging signals present in the RNA genome (PubMed:8943226, PubMed:27671640). Binding of the capsid proteins to the viral RNA induces a conformational change required for efficient T=3 shell formation (PubMed:19913556). The capsid contains also 1 copy of the A2 maturation protein (PubMed:27671640).[1] [2] [3] Acts as a translational repressor of viral replicase synthesis late in infection. This latter function is the result of capsid protein interaction with an RNA hairpin which contains the replicase ribosome-binding site.[4]
References
- ↑ Basnak G, Morton VL, Rolfsson O, Stonehouse NJ, Ashcroft AE, Stockley PG. Viral genomic single-stranded RNA directs the pathway toward a T=3 capsid. J Mol Biol. 2010 Feb 5;395(5):924-36. doi: 10.1016/j.jmb.2009.11.018. Epub 2009, Nov 12. PMID:19913556 doi:http://dx.doi.org/10.1016/j.jmb.2009.11.018
- ↑ Gorzelnik KV, Cui Z, Reed CA, Jakana J, Young R, Zhang J. Asymmetric cryo-EM structure of the canonical Allolevivirus Qbeta reveals a single maturation protein and the genomic ssRNA in situ. Proc Natl Acad Sci U S A. 2016 Sep 26. pii: 201609482. PMID:27671640 doi:http://dx.doi.org/10.1073/pnas.1609482113
- ↑ Lim F, Spingola M, Peabody DS. The RNA-binding site of bacteriophage Qbeta coat protein. J Biol Chem. 1996 Dec 13;271(50):31839-45. PMID:8943226
- ↑ Lim F, Spingola M, Peabody DS. The RNA-binding site of bacteriophage Qbeta coat protein. J Biol Chem. 1996 Dec 13;271(50):31839-45. PMID:8943226
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