1ESY

NMR STRUCTURE OF STEM LOOP SL2 OF THE HIV-1 PSI RNA PACKAGING SIGNAL REVEALS A NOVEL A-U-A BASE-TRIPLE PLATFORM


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 20 
  • Selection Criteria: target function 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

NMR structure of stem-loop SL2 of the HIV-1 psi RNA packaging signal reveals a novel A-U-A base-triple platform.

Amarasinghe, G.K.De Guzman, R.N.Turner, R.B.Summers, M.F.

(2000) J.Mol.Biol. 299: 145-156

  • DOI: 10.1006/jmbi.2000.3710

  • PubMed Abstract: 
  • The genome of the human immunodeficiency virus type-1 (HIV-1) contains a stretch of approximately 120 nucleotides known as the psi-site that is essential for RNA packaging during virus assembly. These nucleotides have been proposed to form four stem- ...

    The genome of the human immunodeficiency virus type-1 (HIV-1) contains a stretch of approximately 120 nucleotides known as the psi-site that is essential for RNA packaging during virus assembly. These nucleotides have been proposed to form four stem-loops (SL1-SL4) that have both independent and overlapping functions. Stem-loop SL2 is important for efficient recognition and packaging of the full-length, unspliced viral genome, and also contains the major splice-donor site (SD) for mRNA splicing. We have determined the structure of the 19-residue SL2 oligoribonucleotide by heteronuclear NMR methods. The structure is generally consistent with the most recent of two earlier secondary structure predictions, with residues G1-G2-C3-G4 and C6-U7 forming standard Watson Crick base-pairs with self-complementary residues C16-G17-C18-C19 and A12-G13, respectively. However, residue A15, which is located near the center of the stem, does not form a predicted bulge, and residues A5 and U14 do not form an expected Watson-Crick base-pair. Instead, these residues form a novel A5-U14-A15 base-triple that appears to be stabilized by hydrogen bonds from A15-H61 and -H62 to A5-N1 and U14-O2, respectively; from A5-H61 to U14-O2, and from C16-H42 to U14-O2'. A kink in the backbone allows the aromatic rings of the sequential U14-A15 residues to be approximately co-planar, adopting a stable "platform motif" that is structurally similar to the A-A (adenosine) platforms observed in the P4-P6 ribozyme domain of the Tetrahymena group I intron. Platform motifs generally function in RNA by mediating long-range interactions, and it is therefore possible that the A-U-A base-triple platform mediates long-range interactions that either stabilize the psi-RNA or facilitate splicing and/or packaging. Residue G8 of the G8-G9-U10-G11 tetraloop is stacked above the U7-A12 base-pair, and the remaining tetraloop residues are disordered and available for potential interactions with either other RNA or protein components.


    Organizational Affiliation

    Howard Hughes Medical Institute, University of Maryland, Baltimore County 21250, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsLengthOrganism
RNA (5'-R(P*GP*GP*CP*GP*AP*CP*UP*GP*GP*UP*GP*AP*GP*UP*AP*CP*GP*CP*C)-3')A19N/A
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 20 
  • Selection Criteria: target function 

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2000-05-31
    Type: Initial release
  • Version 1.1: 2008-04-27
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance