TY - JOUR
T1 - Large-scale effects of transcriptional DNA supercoiling in vivo
AU - Krasilnikov, Andrey S.
AU - Podtelezhnikov, Alexei
AU - Vologodskii, Alexander
AU - Mirkin, Sergei M.
N1 - Funding Information:
We thank all the participants of the 1999 Banbury Conference The role of DNA topology, conformation and associated factors in gene expression for stimulating discussions, Vadim Krivokrysenko for participation in some early experiments, Randal Cox and Gerald Buldak for critical reading of the manuscript, and anonymous reviewers for constructive criticisms. This work was supported by grant GM54247 from the National Institutes of Health to S.M.M.
PY - 1999/10/8
Y1 - 1999/10/8
N2 - The scale of negative DNA supercoiling generated by transcription in Top+ Escherichia coli cells was assessed from the efficiency of cruciform formation upstream of a regulated promoter. An increase in negative supercoiling upon promoter induction led to cruciform formation, which was quantitatively measured by chemical probing of intracellular DNA. By placing a cruciform-forming sequence at varying distances from the promoter, we found that the half-dissociation length of transcription supercoiling wave is ≃800 bp. This is the first proof that transcription can affect DNA structure on such a remarkably large scale in vivo. Moreover, cooperative binding of the cI repressor to the upstream promoter DNA did not preclude efficient diffusion of transcriptional supercoiling. Finally, our plasmids appeared to contain discrete domains of DNA supercoiling, defined by the features and relative orientation of different promoters.
AB - The scale of negative DNA supercoiling generated by transcription in Top+ Escherichia coli cells was assessed from the efficiency of cruciform formation upstream of a regulated promoter. An increase in negative supercoiling upon promoter induction led to cruciform formation, which was quantitatively measured by chemical probing of intracellular DNA. By placing a cruciform-forming sequence at varying distances from the promoter, we found that the half-dissociation length of transcription supercoiling wave is ≃800 bp. This is the first proof that transcription can affect DNA structure on such a remarkably large scale in vivo. Moreover, cooperative binding of the cI repressor to the upstream promoter DNA did not preclude efficient diffusion of transcriptional supercoiling. Finally, our plasmids appeared to contain discrete domains of DNA supercoiling, defined by the features and relative orientation of different promoters.
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U2 - 10.1006/jmbi.1999.3117
DO - 10.1006/jmbi.1999.3117
M3 - Article
C2 - 10512709
AN - SCOPUS:0033536708
SN - 0022-2836
VL - 292
SP - 1149
EP - 1160
JO - Journal of Molecular Biology
JF - Journal of Molecular Biology
IS - 5
ER -