Association of DNA quadruplexes through G:C:G:C tetrads. Solution structure of d(GCGGTGGAT).
Webba da Silva, M.(2003) Biochemistry 42: 14356-14365
- PubMed: 14661946
- DOI: https://doi.org/10.1021/bi0355185
- Primary Citation of Related Structures:
1NYD - PubMed Abstract:
The structure formed by the DNA sequence d(GCGGTGGAT) in a 100 mM Na(+) solution has been determined using molecular dynamics calculations constrained by distance and dihedral restraints derived from NMR experiments performed at isotopic natural abundance. The sequence folds into a dimer of dimers. Each symmetry-related half contains two parallel stranded G:G:G:G tetrads flanked by an A:A mismatch and by four-stranded G:C:G:C tetrads. Each of the two juxtaposed G:C:G:C tetrads is composed of alternating antiparallel strands from the two halves of the dimer. For each single strand, a thymine intersperses a double chain reversal connecting the juxtaposed G:G:G:G tetrads. This architecture has potential implications in genetic recombination. It suggests a pathway for oligomerization involving association of quadruplex entities through GpC steps.
Organizational Affiliation:
Cellular Biochemistry and Biophysics Program, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, New York 10021, USA. mateus@webbas.org