6n8f: Difference between revisions
From Proteopedia
Jump to navigationJump to search
No edit summary |
No edit summary |
||
| Line 1: | Line 1: | ||
==RNA Duplex containing the internal loop 5'-GCUU/3'-UUCG== | |||
<StructureSection load='6n8f' size='340' side='right' caption='[[6n8f]], [[NMR_Ensembles_of_Models | 20 NMR models]]' scene=''> | |||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[6n8f]] is a 2 chain structure. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6N8F OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6N8F FirstGlance]. <br> | |||
</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=6n8f FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6n8f OCA], [http://pdbe.org/6n8f PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=6n8f RCSB], [http://www.ebi.ac.uk/pdbsum/6n8f PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=6n8f ProSAT]</span></td></tr> | |||
</table> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
RNA thermodynamics play an important role in determining the two- and three-dimensional structures of RNA. Internal loops of the sequence 5'-GMNU/3'-UNMG are relatively unstable thermodynamically. Here, five duplexes with GU-flanked 2 x 2 nucleotide internal loops were structurally investigated to reveal determinants of their instability. The following internal loops were investigated: 5'-GCAU/3'-UACG, 5'-UUCG/3'-GCUU, 5'-GCUU/3'-UUCG, 5'-GUCU/3'-UCUG, and 5'-GCCU/3'-UCCG. Two-dimensional nuclear magnetic resonance spectra indicate the absence of GU wobble base pairing in 5'-GCUU/3'-UUCG, 5'-GUCU/3'-UCUG, and 5'-GCCU/3'-UCCG. The 5'-GCUU/3'-UUCG loop has an unusual conformation of the GU base pairs, in which U's O2 carbonyl forms a bifurcated hydrogen bond with G's amino and imino protons. The internal loop of 5'-GUCU/3'-UCUG displays a shifted configuration in which GC pairs flank a U-U pair and several U's are in fast exchange between positions inside and outside the helix. In contrast, 5'-GCAU/3'-UACG and 5'-UUCG/3'-GCUU both have the expected GU wobble base pairs flanking the internal loop. Evidently, GU base pairs flanking internal loops are more likely to display atypical structures relative to Watson-Crick base pairs flanking internal loops. This appears to be more likely when the G of the GU pair is 5' to the loop. Such unusual structures could serve as recognition elements for biological function and as benchmarks for structure prediction methods. | |||
Nuclear Magnetic Resonance Reveals That GU Base Pairs Flanking Internal Loops Can Adopt Diverse Structures.,Berger KD, Kennedy SD, Turner DH Biochemistry. 2019 Jan 31. doi: 10.1021/acs.biochem.8b01027. PMID:30702283<ref>PMID:30702283</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
[[Category: | </div> | ||
[[Category: | <div class="pdbe-citations 6n8f" style="background-color:#fffaf0;"></div> | ||
[[Category: Turner, D | == References == | ||
[[Category: | <references/> | ||
__TOC__ | |||
</StructureSection> | |||
[[Category: Berger, K D]] | |||
[[Category: Kennedy, S D]] | |||
[[Category: Turner, D H]] | |||
[[Category: Bifurcated gu]] | |||
[[Category: Duplex]] | |||
[[Category: Internal loop]] | |||
[[Category: Rna]] | |||
[[Category: Uc pair]] | |||