Linked Life Data

1947004

Source:http://linkedlifedata.com/resource/pubmed/id/1947004

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1991-12-11
pubmed:abstractText
The Escherichia coli supF gene encoding the suppressor tyrosine tRNA in a human shuttle plasmid, pZ189, was used as a target for molecular analysis of X-ray-induced mutations in human lymphoblastoid cells. Following replication of the in vitro-irradiated plasmid in human cells, the mutant supF-containing molecules were cloned by phenotypic screening in E. coli and the nature of the mutations was determined by direct sequencing of the tRNA gene. At 160 Gy the mutant frequency was 13 times (0.39%) that observed in unirradiated controls (0.031%). When control plasmid was replicated directly in E. coli, the mutant frequency was 16 times less than that of the plasmid passaged through the human cells. The distribution of mutations was highly nonrandom and remarkably similar in both irradiated and control DNAs. The majority of the mutations were transitions involving G.C pairs and occurred selectively at most 5'-TC (3'-AG) sequences. These mutations at C's were preferentially distributed in the nontranscribed strand. We propose that mutations in the control plasmid result from oxidative damages that occur during and/or after its incorporation into human cells and that these damages are similar to those induced by ionizing radiation. The hot spots for mutations suggest that the proximate nucleotide sequence and the overall conformation of the target DNA are important in the production and/or processing of these damages during repair and replication.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0033-7587
pubmed:author
pubmed:issnType
Print
pubmed:volume
127
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
190-201
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
Mutations induced by ionizing radiation in a plasmid replicated in human cells. I. Similar, nonrandom distribution of mutations in unirradiated and X-irradiated DNA.
pubmed:affiliation
Biology Division, Oak Ridge National Laboratory, Tennessee.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.