8-Methylguanosine: a powerful Z-DNA stabilizer.
Various modified guanine derivatives were synthesized and introduced into G(4) of d(CGCGCG)(2) to evaluate their capacity to stabilize Z-form DNA. It was found that the incorporation of 8-methylguanosine (m(8)rG) in oligonucleotides stabilizes the Z form more dramatically than does the incorporation of 8-methyl-2'-deoxyguanosine (m(8)G). This enhancement is ascribed to a reduction in the entropic penalty, which arises from the introduction of hydrophilic groups in solvent-exposed regions. The incorporation of m(8)rG into DNA sequences markedly stabilizes the Z form even in the absence of NaCl. The Z-DNA stabilizer allows oligonucleotides with a wide range of sequences to be converted to the Z form. It could be a powerful tool for examining the molecular basis of many types of Z-form-specific reactions at the molecular level under physiological salt conditions.
Xu
Yan
Y
Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, Chiyoda, Tokyo 101-0062, Japan.
Ikeda
Reiko
R
Sugiyama
Hiroshi
H
D002942:Circular Dichroism; D043542:DNA, Z-Form / Q000737:chemistry* / Q000378:metabolism; D006151:Guanosine / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry* / Q000378:metabolism; D008958:Models, Molecular; D009690:Nucleic Acid Conformation; D009841:Oligonucleotides / Q000138:chemical synthesis / Q000737:chemistry / Q000378:metabolism; D013816:Thermodynamics
C116616:8-methylguanosine; D043542:DNA, Z-Form; D009841:Oligonucleotides; D006151:Guanosine