1NZ1

Solution structure of the S. cerevisiae U6 Intramolecular stem-loop containing an SP phosphorothioate at nucleotide U80


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 17 
  • Selection Criteria: structures with the lowest energy 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structure of the U6 RNA intramolecular stem-loop harboring an S(P)-phosphorothioate modification.

Reiter, N.J.Nikstad, L.J.Allman, A.M.Johnson, R.J.Butcher, S.E.

(2003) RNA 9: 533-542

  • Primary Citation of Related Structures:  
  • Also Cited By: 2KF0, 2KEZ

  • PubMed Abstract: 
  • Phosphorothioate-substitution experiments are often used to elucidate functionally important metal ion-binding sites on RNA. All previous experiments with S(P)-phosphorothioate-substituted RNAs have been done in the absence of structural information ...

    Phosphorothioate-substitution experiments are often used to elucidate functionally important metal ion-binding sites on RNA. All previous experiments with S(P)-phosphorothioate-substituted RNAs have been done in the absence of structural information for this particular diastereomer. Yeast U6 RNA contains a metal ion-binding site that is essential for spliceosome function and includes the pro-S(P) oxygen 5' of U(80). S(P)-phosphorothioate substitution at this location creates spliceosomes dependent on thiophilic ions for the first step of splicing. We have determined the solution structure of the U(80) S(P)-phosphorothioate-substituted U6 intramolecular stem-loop (ISL), and also report the refined NMR structure of the unmodified U6 ISL. Both structures were determined with inclusion of (1)H-(13)C residual dipolar couplings. The precision of the structures with and without phosphorothioate (RMSD = 1.05 and 0.79 A, respectively) allows comparison of the local and long-range structural effect of the modification. We find that the U6-ISL structure is unperturbed by the phosphorothioate. Additionally, the thermodynamic stability of the U6 ISL is dependent on the protonation state of the A(79)-C(67) wobble pair and is not affected by the adjacent phosphorothioate. These results indicate that a single S(P)-phosphorothioate substitution can be structurally benign, and further validate the metal ion rescue experiments used to identify the essential metal-binding site(s) in the spliceosome.


    Organizational Affiliation

    Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsLengthOrganism
SP U6 Intramolecular Stem-Loop RNAA24N/A
Small Molecules
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
SSU
Query on SSU
A
RNA LINKINGC9 H13 N2 O8 P SU
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 17 
  • Selection Criteria: structures with the lowest energy 

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2003-05-13
    Type: Initial release
  • Version 1.1: 2008-04-29
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance