Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4928
pubmed:dateCreated
1989-11-13
pubmed:abstractText
Biological processes such as transcription may generate domains of supercoiling on a circular DNA. The existence of these domains in Escherichia coli was investigated by the ability of different lengths of (CG) tracts, cloned upstream or downstream from the tetracycline resistance gene (tet) of pBR322, to adopt the Z structure in vivo. Segments as short as 12 base pairs adopt the Z form when cloned upstream from the tet gene (Eco RI site), whereas no Z DNA was detected when this sequence was cloned downstream (Sty I site), even with a 74-base pair (CG) tract that requires less supercoiling than shorter tracts for the B-Z transition. Hence the localized supercoil density in pBR322 can be as high as -0.038 and as low as -0.021 at different loci. These data demonstrate the existence of the Z structure for commonly found natural sequences and support the notion of domains of negative supercoiling in vivo.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0036-8075
pubmed:author
pubmed:issnType
Print
pubmed:day
20
pubmed:volume
246
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
358-63
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
Stabilization of Z DNA in vivo by localized supercoiling.
pubmed:affiliation
Department of Biochemistry, School of Medicine, University of Alabama, Birmingham 35294.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.