2MRZ

Dimeric structure of the Human A-box


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 10 
  • 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

Centromeric Alpha-Satellite DNA Adopts Dimeric i-Motif Structures Capped by AT Hoogsteen Base Pairs.

Garavis, M.Escaja, N.Gabelica, V.Villasante, A.Gonzalez, C.

(2015) Chemistry 21: 9816-9824

  • DOI: 10.1002/chem.201500448

  • PubMed Abstract: 
  • Human centromeric alpha-satellite DNA is composed of tandem arrays of two types of 171 bp monomers; type A and type B. The differences between these types are concentrated in a 17 bp region of the monomer called the A/B box. Here, we have determined ...

    Human centromeric alpha-satellite DNA is composed of tandem arrays of two types of 171 bp monomers; type A and type B. The differences between these types are concentrated in a 17 bp region of the monomer called the A/B box. Here, we have determined the solution structure of the C-rich strand of the two main variants of the human alpha-satellite A box. We show that, under acidic conditions, the C-rich strands of two A boxes self-recognize and form a head-to-tail dimeric i-motif stabilized by four intercalated hemi-protonated C:C(+) base pairs. Interestingly, the stack of C:C(+) base pairs is capped by T:T and Hoogsteen A:T base pairs. The two main variants of the A box adopt a similar three-dimensional structure, although the residues involved in the formation of the i-motif core are different in each case. Together with previous studies showing that the B box (known as the CENP-B box) also forms dimeric i-motif structures, our finding of this non-canonical structure in the A box shows that centromeric alpha satellites in all human chromosomes are able to form i-motifs, which consequently raises the possibility that these structures may play a role in the structural organization of the centromere.


    Organizational Affiliation

    Instituto de Química Física Rocasolano, CSIC, Serrano 119, 28006 Madrid (Spain).




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsLengthOrganism
DNA (5'-D(P*TP*CP*CP*TP*TP*TP*TP*CP*CP*A)-3')A,B10synthetic construct
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 10 
  • 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: 2015-06-03
    Type: Initial release
  • Version 1.1: 2015-07-15
    Type: Database references