The sequence (dC-dA)n X (dG-dT)n forms left-handed Z-DNA in negatively supercoiled plasmids.
AUTOR(ES)
Nordheim, A
RESUMO
Z-DNA-specific antibodies have been used to demonstrate the formation of left-handed Z-DNA in sequences of (dC-dA)32 X (dG-dT)32 in negatively supercoiled plasmids. Z-DNA was found to form at physiological negative superhelical densities (sigma = -0.05) in the absence of high salt concentration or chemical modifications. The binding site of the antibody to the DNA sequences was demonstrated by crosslinking experiments. (dC-dA)n X (dG-dT)n sequences are widespread in eukaryotic DNA, and possible roles for such Z elements in chromatin activation or genome rearrangements are suggested.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=393701Documentos Relacionados
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