Linked Life Data

17049932

Source:http://linkedlifedata.com/resource/pubmed/id/17049932

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2007-1-2
pubmed:abstractText
Mutations of the Xpc gene cause a deficiency in global genome repair, a subpathway of nucleotide excision repair (NER), in mammalian cells. We used transgenic mice harboring the lambda-phage-based lacZ mutational reporter gene to study the effect of an Xpc null mutation (Xpc-/-) on damage induction, repair and mutagenesis in mouse skin epidermis after UVB irradiation. UVB induced equal amounts of cyclobutane pyrimidine dimers (CPDs) and pyrimidine(6-4)pyrimidone photoproducts (64PPs) in mouse skin epidermis of Xpc-/- and wild-type mice. CPDs were not significantly removed in either of the mouse genotypes by 12h after irradiation, whereas removal of 64PPs was observed in the wild-type. Irradiation with 300 and 400J/m2 UVB increased the lacZ mutant frequency in the Xpc-/- epidermis to at least twice as high as in the wild-type. Ninety-nine lacZ mutants isolated from the UVB-exposed epidermis of Xpc(-/-)mice were analyzed and compared with mutant sequences from irradiated wild-type mice. The spectra of the mutations in the two genotypes were both highly UV-specific and similar in the dominance of C-->T transitions at dipyrimidine sites; however, Xpc-/- mice had a higher frequency of two-base tandem substitutions, including CC-->TT mutations, three-base tandem substitutions and double base substitutions that were separated by one unchanged base in a three-base sequence (alternating mutations). These tandem/alternating mutations included a remarkably large number of triplet mutations, a recently reported, novel type of UV-specific mutation, characterized by multiple base substitutions or frameshifts within a three-nucleotide sequence containing a dipyrimidine. We concluded that the triplet mutation is a UV-specific mutation that preferably occurs in NER deficient genetic backgrounds.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
1568-7864
pubmed:author
pubmed:issnType
Print
pubmed:day
4
pubmed:volume
6
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
82-93
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Frequent recovery of triplet mutations in UVB-exposed skin epidermis of Xpc-knockout mice.
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