Crystal structure of a junction between B-DNA and Z-DNA reveals two extruded bases

@article{Ha2005CrystalSO,
  title={Crystal structure of a junction between B-DNA and Z-DNA reveals two extruded bases},
  author={Sung Chul Ha and Ky Lowenhaupt and Alexander Rich and Yang‐Gyun Kim and Kyeong Kyu Kim},
  journal={Nature},
  year={2005},
  volume={437},
  pages={1183-1186}
}
Left-handed Z-DNA is a higher-energy form of the double helix, stabilized by negative supercoiling generated by transcription or unwrapping nucleosomes. Regions near the transcription start site frequently contain sequence motifs favourable for forming Z-DNA, and formation of Z-DNA near the promoter region stimulates transcription. Z-DNA is also stabilized by specific protein binding; several proteins have been identified with low nanomolar binding constants. Z-DNA occurs in a dynamic state… 
Crystal structure of a junction between two Z-DNA helices
TLDR
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NMR study on the B-Z junction formation of DNA duplexes induced by Z-DNA binding domain of human ADAR1.
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Intrinsic Z-DNA is stabilized by the conformational selection mechanism of Z-DNA-binding proteins.
TLDR
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Sequence-specific B-DNA flexibility modulates Z-DNA formation.
TLDR
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Incorporation of CC steps into Z-DNA: interplay between B-Z junction and Z-DNA helical formation.
TLDR
A method for characterizing sequence-specific preferences for Z-DNA formation and B-Z junction localization within heterogeneous DNA duplexes is developed that is based on combining 2-aminopurine fluorescence measurements with a new quantitative application of circular dichroism spectroscopy for determining the fraction of B- versus Z- DNA.
Molecular biology: DNA twists and flips
TLDR
The determination of the crystal structure of the junction between left-handed DNA and ‘normal’, right-handedDNA or B-DNA is determined, showing that the junction is very tight, and that a base pair is pushed out of the double helix, one base on each side of the Junction.
Z-DNA, an active element in the genome.
TLDR
Accumulating experimental and clinical evidence support the idea that this non-B DNA conformation is involved in several important biological processes and may provide a target for the prevention and treatment of some human diseases.
Unveiling the pathway to Z-DNA in the protein-induced B–Z transition
TLDR
This study shows the stable B* state supports the active picture for the protein-induced B–Z transition that occurs under a physiological setting and quantitatively determines quantitatively the affinities of ADAR1 to both Z-form and B-form of these sequences.
Protein-induced B-Z transition of DNA duplex containing a 2'-OMe guanosine.
Energetics of Z-DNA binding protein-mediated helicity reversals in DNA, RNA, and DNA-RNA duplexes.
TLDR
The use of single-molecule fluorescence resonance energy transfer (FRET) is used to determine the energetics of Z-form stabilization by ZBP for DNA, RNA, and DNA-RNA duplexes, revealing that the formation of B-Z or A-Z junctions dominates the thermodynamics and kinetics of Z -form stabilization.
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