Linked Life Data

6263893

Source:http://linkedlifedata.com/resource/pubmed/id/6263893

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
1981-8-10
pubmed:abstractText
We have developed a novel method for studying the ability to wheat germ RNA polymerase II to initiate transcription in vitro on unnicked duplex DNA template. Our template is a plasmid which has been relaxed in vitro with wheat germ DNA topoisomerase I. The plasmid consists of SV40 cloned in pBR322. We transcribe briefly to synthesize highly labeled nascent RNA, then fractionate the resulting ternary complexes on an agarose gel to separate relaxed, closed circular DNA from other DNA species contaminating the template preparation. Under optimal conditions, we recover about half of the total RNA synthesized in complex with relaxed, closed circular DNA. The remaining RNA is in association with other DNA species or is free in solution. The principal conclusions we draw from these studies are: 1) relaxed, closed circular DNA can serve as a template for in vitro transcription, although the relative efficiencies of transcription are such that even a few per cent contamination with nicked or supercoiled template can cause transcription from these forms to dominate the reaction. 2) Initiation occurs on approximately 1 in 25 cloned circular molecules in the course of a 5-min reaction, under optimal conditions. This transcription is not predominantly from SV40 in vivo promoters and is either random or from a sufficient number of sites as to appear random. 3) There is a striking dependence of initiation frequency on purine nucleoside triphosphate concentration, especially with GTP.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
10
pubmed:volume
256
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
5866-73
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1981
pubmed:articleTitle
In vitro transcription by wheat germ RNA polymerase II. Initiation of RNA synthesis on relaxed, closed circular template.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.