2ldl

<StructureSection load='2ldl' size='340' side='right'caption='[[2ldl]], [[NMR_Ensembles_of_Models | 12 NMR models]]' scene=''>

<table><tr><td colspan='2'>[[2ldl]] is a 1 chain structure. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2LDL OCA]. For a <b>guided tour on the structure components</b> use [http://proteopedia.org/fgij/fg.htm?mol=2LDL FirstGlance]. <br>

</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=2ldl FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2ldl OCA], [http://pdbe.org/2ldl PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=2ldl RCSB], [http://www.ebi.ac.uk/pdbsum/2ldl PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=2ldl ProSAT]</span></td></tr>

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== Publication Abstract from PubMed ==

Alternative splicing of the human immunodeficiency virus type 1 (HIV-1) genomic RNA is necessary to produce the complete viral protein complement, and aberrations in the splicing pattern impair HIV-1 replication. Genome splicing in HIV-1 is tightly regulated by the dynamic assembly/disassembly of trans host factors with cis RNA control elements. The host protein, heterogeneous nuclear ribonucleoprotein (hnRNP) A1, regulates splicing at several highly conserved HIV-1 3' splice sites by binding 5'-UAG-3' elements embedded within regions containing RNA structure. The physical determinants of hnRNP A1 splice site recognition remain poorly defined in HIV-1, thus precluding a detailed understanding of the molecular basis of the splicing pattern. Here, the three-dimensional structure of the exon splicing silencer 3 (ESS3) from HIV-1 has been determined using NMR spectroscopy. ESS3 adopts a 27-nucleotide hairpin with a 10-bp A-form stem that contains a pH-sensitive A(+)C wobble pair. The seven-nucleotide hairpin loop contains the high-affinity hnRNP-A1-responsive 5'-UAGU-3' element and a proximal 5'-GAU-3' motif. The NMR structure shows that the heptaloop adopts a well-organized conformation stabilized primarily by base stacking interactions reminiscent of a U-turn. The apex of the loop is quasi-symmetric with UA dinucleotide steps from the 5'-GAU-3' and 5'-UAGU-3' motifs stacking on opposite sides of the hairpin. As a step towards understanding the binding mechanism, we performed calorimetric and NMR titrations of several hnRNP A1 subdomains into ESS3. The data show that the UP1 domain forms a high-affinity (K(d)=37.8+/-1.1 nM) complex with ESS3 via site-specific interactions with the loop.

Solution Structure of the HIV-1 Exon Splicing Silencer 3.,Levengood JD, Rollins C, Mishler CH, Johnson CA, Miner G, Rajan P, Znosko BM, Tolbert BS J Mol Biol. 2011 Nov 29. PMID:22154809<ref>PMID:22154809</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 2ldl" style="background-color:#fffaf0;"></div>

== References ==

<references/>

[[Category: Johnson, C A]]

[[Category: Levengood, J D]]

[[Category: Mishler, C]]

[[Category: Rajan, P]]

[[Category: Znosko, B M]]

[[Category: Rna]]