2MBJ

Structure of an antiparallel (2+2) G-quadruplex formed by human telomeric repeats in Na+ solution (with G22-to-BrG substitution)


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 10 
  • Selection Criteria: structures with the lowest energy 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Structure of the human telomere in Na+ solution: an antiparallel (2+2) G-quadruplex scaffold reveals additional diversity.

Lim, K.W.Ng, V.C.Martin-Pintado, N.Heddi, B.Phan, A.T.

(2013) Nucleic Acids Res. 41: 10556-10562

  • DOI: 10.1093/nar/gkt771

  • PubMed Abstract: 
  • Single-stranded DNA overhangs at the ends of human telomeric repeats are capable of adopting four-stranded G-quadruplex structures, which could serve as potential anticancer targets. Out of the five reported intramolecular human telomeric G-quadruple ...

    Single-stranded DNA overhangs at the ends of human telomeric repeats are capable of adopting four-stranded G-quadruplex structures, which could serve as potential anticancer targets. Out of the five reported intramolecular human telomeric G-quadruplex structures, four were formed in the presence of K(+) ions and only one in the presence of Na(+) ions, leading often to a perception that this structural polymorphism occurs exclusively in the presence of K(+) but not Na(+). Here we present the structure of a new antiparallel (2+2) G-quadruplex formed by a derivative of a 27-nt human telomeric sequence in Na(+) solution, which comprises a novel core arrangement distinct from the known topologies. This structure complements the previously elucidated basket-type human telomeric G-quadruplex to serve as reference structures in Na(+)-containing environment. These structures, together with the coexistence of other conformations in Na(+) solution as observed by nuclear magnetic resonance spectroscopy, establish the polymorphic nature of human telomeric repeats beyond the influence of K(+) ions.


    Organizational Affiliation

    School of Physical and Mathematical Sciences, Nanyang Technological University, 637371 Singapore, School of Biological Sciences, Nanyang Technological University, 637551 Singapore and Instituto de Química Física Rocasolano, CSIC, 28006 Madrid, Spain.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsLengthOrganism
DNA_(27-MER)A27N/A
Small Molecules
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
BGM
Query on BGM
A
DNA LINKINGC10 H13 Br N5 O7 PDG
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 10 
  • 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: 2013-09-18
    Type: Initial release
  • Version 1.1: 2014-01-08
    Type: Database references