View source for 6bux


==CRYSTAL STRUCTURE OF APOBEC3G CATALYTIC DOMAIN COMPLEX WITH SUBSTRATE SSDNA==
<StructureSection load='6bux' size='340' side='right'caption='[[6bux]], [[Resolution|resolution]] 1.86&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6bux]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] and [https://en.wikipedia.org/wiki/Synthetic_construct Synthetic construct]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6BUX OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=6BUX 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]] 1.856&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <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=6bux FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6bux OCA], [https://pdbe.org/6bux PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=6bux RCSB], [https://www.ebi.ac.uk/pdbsum/6bux PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=6bux ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/ABC3G_HUMAN ABC3G_HUMAN] DNA deaminase (cytidine deaminase) that mediates a form of innate resistance to retroviral infections (at least to HIV-1 infection) by triggering G-to-A hypermutation in the newly synthesized viral DNA. The replacements C-to-U in the minus strand DNA of HIV-1 during reverse transcription, leads to G-to-A transitions in the plus strand. The inhibition of viral replication is either due to the degradation of the minus strand before its integration or to the lethality of the hypermutations. Modification of both DNA strands is not excluded. This antiviral activity is neutralized by the virion infectivity factor (VIF), that prevents the incorporation of APOBEC3G into progeny HIV-1 virions by both inhibiting its translation and/or by inducing its ubiquitination and subsequent degradation by the 26S proteasome. May also prevent the transposition of a subset of retroelements. Binds a variety of RNAs, but does not display detectable APOB, NF1 and NAT1 mRNA editing.<ref>PMID:14557625</ref> <ref>PMID:12167863</ref> <ref>PMID:12808466</ref> <ref>PMID:12809610</ref> <ref>PMID:12808465</ref> <ref>PMID:12859895</ref> <ref>PMID:12970355</ref> <ref>PMID:14528300</ref> <ref>PMID:15031497</ref> <ref>PMID:16527742</ref> <ref>PMID:21123384</ref> <ref>PMID:18288108</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The human APOBEC3G protein is a cytidine deaminase that generates cytidine to deoxy-uridine mutations in single-stranded DNA (ssDNA), and capable of restricting replication of HIV-1 by generating mutations in viral genome. The mechanism by which APOBEC3G specifically deaminates 5'-CC motifs has remained elusive since structural studies have been hampered due to apparently weak ssDNA binding of the catalytic domain of APOBEC3G. We overcame the problem by generating a highly active variant with higher ssDNA affinity. Here, we present the crystal structure of this variant complexed with a ssDNA substrate at 1.86 A resolution. This structure reveals atomic-level interactions by which APOBEC3G recognizes a functionally-relevant 5'-TCCCA sequence. This complex also reveals a key role of W211 in substrate recognition, implicating a similar recognition in activation-induced cytidine deaminase (AID) with a conserved tryptophan.

Crystal structure of the catalytic domain of HIV-1 restriction factor APOBEC3G in complex with ssDNA.,Maiti A, Myint W, Kanai T, Delviks-Frankenberry K, Sierra Rodriguez C, Pathak VK, Schiffer CA, Matsuo H Nat Commun. 2018 Jun 25;9(1):2460. doi: 10.1038/s41467-018-04872-8. PMID:29941968<ref>PMID:29941968</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 6bux" style="background-color:#fffaf0;"></div>
== References ==
<references/>
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</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Synthetic construct]]
[[Category: Maiti A]]
[[Category: Matsuo H]]