1XV0

Solution NMR structure of RNA internal loop with three consecutive sheared GA pairs in 5'GGUGGAGGCU/3'PCCGAAGCCG


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 40 
  • Conformers Submitted: 33 
  • Selection Criteria: structures with the least restraint violations 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Solution Structure of an RNA Internal Loop with Three Consecutive Sheared GA Pairs

Chen, G.Znosko, B.M.Kennedy, S.D.Krugh, T.R.Turner, D.H.

(2005) Biochemistry 44: 2845-2856

  • DOI: https://doi.org/10.1021/bi048079y
  • Primary Citation of Related Structures:  
    1XV0

  • PubMed Abstract: 

    Internal loops in RNA are important for folding and function. Many folding motifs are internal loops containing GA base pairs, which are usually thermodynamically stabilizing, i.e., contribute favorable free energy to folding. Understanding the sequence dependence of folding stability and structure in terms of molecular interactions, such as hydrogen bonding and base stacking, will provide a foundation for predicting stability and structure. Here, we report the NMR structure of the oligonucleotide duplex, 5'GGUGGAGGCU3'/3'PCCGAAGCCG5' (P = purine), containing an unusually stable and relatively abundant internal loop, 5'GGA3'/3'AAG5'. This loop contains three consecutive sheared GA pairs (trans Hoogsteen/Sugar edge AG) with separate stacks of three G's and three A's in a row. The thermodynamic consequences of various nucleotide substitutions are also reported. Significant destabilization of approximately 2 kcal/mol at 37 degrees C is found for substitution of the middle GA with AA to form 5'GAA3'/3'AAG5'. This destabilization correlates with a unique base stacking and hydrogen-bonding network within the 5'GGA3'/3'AAG5' loop. Interestingly, the motifs, 5'UG3'/3'GA5' and 5'UG3'/3'AA5', have stability similar to 5'CG3'/3'GA5' even though UG and UA pairs are usually less stable than CG pairs. Consecutive sheared GA pairs in the 5'GGA3'/3'AAG5' loop are preorganized for potential tertiary interactions and ligand binding.


  • Organizational Affiliation

    Department of Chemistry, University of Rochester, Rochester, New York 14627, USA.


Macromolecules

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Entity ID: 1
MoleculeChains LengthOrganismImage
5'-R(*GP*GP*UP*GP*GP*AP*GP*GP*CP*U)-3'10N/A
Sequence Annotations
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  • Reference Sequence

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Entity ID: 2
MoleculeChains LengthOrganismImage
5'-R(*GP*CP*CP*GP*AP*AP*GP*CP*CP*(P5P)-3'10N/A
Sequence Annotations
Expand
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 40 
  • Conformers Submitted: 33 
  • Selection Criteria: structures with the least restraint violations 

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2004-11-09
    Type: Initial release
  • Version 1.1: 2008-04-30
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2022-03-02
    Changes: Data collection, Database references, Derived calculations