Linked Life Data

15491628

Source:http://linkedlifedata.com/resource/pubmed/id/15491628

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
2004-10-19
pubmed:abstractText
We studied the mutations induced in skin by sunlight using transgenic Muta mice. Noon sunlight during summer at Sendai, Japan induced mutations efficiently in both epidermis and dermis. The mutant frequency (MF) in epidermis reached nearly 0.5% during the first 40 min irradiation but became saturated at this level with the appearance of skin inflammation after further irradiation. At the equivalent inflammatory dose, sunlight was twice as genotoxic as 313 nm-peak UVB. The 81 mutations detected in 80 lacZ transgene mutants isolated from the sunlight-exposed epidermis were dominated by C --> T transitions (89%), occurring exclusively at dipyrimidine sites, and also included a CC --> TT tandem substitution. Thus, the sunlight-induced mutation spectrum is highly UV-specific, quite similar to that induced by UVB but significantly different from that induced by UVA. Although oxidative damage-related C --> A transversions were detected only in five mutants (6%), their frequency was elevated to at least 15 times the background level, suggesting that the contribution of UVA-mediated oxidative stress is comparatively small but considerable. An analysis of bases adjacent to the mutated cytosines revealed that the sunlight-induced mutations prefer 5'-TC-3' dipyrimidine sites to 5'-CC-3' and 5'-CT-3'. The distribution of the frequent C --> T transition sites in the transgene was well associated with the CpG motif, which is known to be completely methylated in the gene, and quite similar to that induced by UVB rather than that by UVA. Thus, the UVB component contributes to the sunlight-induced mutations in the mammalian skin much more than the UVA component, whose influence through reactive oxygen species (ROS)-mediated mutagenesis is still appreciable.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0027-5107
pubmed:author
pubmed:issnType
Print
pubmed:day
22
pubmed:volume
556
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
11-24
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Mutation spectrum in sunlight-exposed mouse skin epidermis: small but appreciable contribution of oxidative stress-mediated mutagenesis.
pubmed:affiliation
Department of Cell Biology, Graduate School of Medicine, Tohoku University, Sendai 980-8575, Japan. ikehata@mail.tains.tohoku.ac.jp
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't