Linked Life Data

6547848

Source:http://linkedlifedata.com/resource/pubmed/id/6547848

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
13
pubmed:dateCreated
1984-9-26
pubmed:abstractText
The sedimentation of DNA-nuclear protein complexes in 1.9 M salt-neutral sucrose gradients (nucleoid sedimentation) was used to examine the effects of the DNA intercalator 4'-(9-acridinylamino)methanesulfon-m-anisidide (m-AMSA) on mouse leukemia cell DNA. Mild detergent cell lysis and neutral pH make nucleoid sedimentation an extremely gentle, but sensitive, method to detect DNA scission. DNA breaks reduce the compaction of nucleoids and slow their sedimentation. Nucleoids from m-AMSA-treated cells sedimented as did those from untreated cells, indicating no detectable m-AMSA-dependent alterations in compaction despite an apparent underlying DNA break frequency of approximately 3 per 10(6) nucleotides, as measured by alkaline elution with proteinase. Mild proteinase digestion of cell lysates prior to nucleoid sedimentation unmasked some, but not all, of the underlying breaks. The frequency of DNA-protein cross-links in nucleoids from cells treated with m-AMSA was comparable to the single-strand break frequency produced by m-AMSA in whole cells. These results indicate that m-AMSA-induced DNA-protein cross-links conceal DNA breaks so as to prevent swiveling around the breaks within the nucleoids. This unique sort of DNA scission is consistent with the involvement of topoisomerases in the DNA breaks elicited by intercalators in mammalian cells.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
19
pubmed:volume
23
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2922-7
pubmed:dateRevised
2003-11-14
pubmed:meshHeading
pubmed:year
1984
pubmed:articleTitle
Absence of swiveling at sites of intercalator-induced protein-associated deoxyribonucleic acid strand breaks in mammalian cell nucleoids.
pubmed:publicationType
Journal Article