Linked Life Data

11677235

Source:http://linkedlifedata.com/resource/pubmed/id/11677235

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
52
pubmed:dateCreated
2001-12-25
pubmed:abstractText
Cyclopurine deoxynucleosides are common DNA lesions generated by exposure to reactive oxygen species under hypoxic conditions. The S and R diastereoisomers of cyclodeoxyadenosine on DNA were investigated separately for their ability to block 3' to 5' exonucleases. The mammalian DNA-editing enzyme DNase III (TREX1) was blocked by both diastereoisomers, whereas only the S diastereoisomer was highly efficient in preventing digestion by the exonuclease function of T4 DNA polymerase. Digestion in both cases was frequently blocked one residue before the modified base. Oligodeoxyribonucleotides containing a cyclodeoxyadenosine residue were further employed as templates for synthesis by human DNA polymerase eta (pol eta). pol eta could catalyze translesion synthesis on the R diastereoisomer of cyclodeoxyadenosine. On the S diastereoisomer, pol eta could catalyze the incorporation of one nucleotide opposite the lesion but could not continue elongation. Although pol eta preferentially incorporated dAMP opposite the R diastereoisomer, elongation continued only when dTMP was incorporated, suggesting bypass of this lesion by pol eta with reasonable fidelity. With the S diastereoisomer, pol eta mainly incorporated dAMP or dTMP opposite the lesion but could not elongate even after incorporating a correct nucleotide. These data suggest that the S diastereoisomer may be a more cytotoxic DNA lesion than the R diastereoisomer.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
28
pubmed:volume
276
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
49283-8
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Oxygen free radical damage to DNA. Translesion synthesis by human DNA polymerase eta and resistance to exonuclease action at cyclopurine deoxynucleoside residues.
pubmed:affiliation
Imperial Cancer Research Fund, Clare Hall Laboratories, South Mimms, Hertfordshire EN6 3LD, United Kingdom.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't