Mutagenesis vol. 8 no. 2 pp. 155-161, 1993
© 1993 UK Environmental Mutagen Society/Oxford University Press
research-article |
A single-site mutation in the XPAC gene alters photoproduct recognition
Laboratory of Radiobiology and Environmental Health, Box 0750, University of California San Francisco, CA 94143-0750, USA
The XPAC (xerodenna pigmentosum group A complementing) gene, which is located on chromosome 9, carries a variety of point mutations in XP group A patients. We investigated the role of the XPAC gene product in excision repair by generating revertants of an XP group A cell line (XP12RO) that have increased resistance to ultraviolet light. One of these cell lines, XP129, can repair (64) pyrimidine-pyrimidone photoproducts normally but has reduced repair of cyclobutane dimers, as in XP12RO. Sequence analysis of cDNA from the XPAC gene indicated that XP12RO contains a termination codon at amino acid position 207, resulting in a reduced amount of mRNA and no detectable protein. In the revertant XP129 line, this termination codon has been mutated further and now encodes giycine in one allele instead of the wild-type arginine. The mRNA level detected by allelespecific polymerase chain reaction amplification was greater for the reverted sequence than for the chain-terminating sequence. These observations indicated that a point mutation resulting in a mis-sense mutation in the XPAC gene and altered expression of the XPAC protein can alter the substrate specificity of the excision repair system, and imply that the XPAC gene product plays an important role in photoproduct recognition.
1To whom correspondence should be sent
![]()
CiteULike
Connotea
Del.icio.us What's this?
This article has been cited by other articles:
![]() |
V. Rapic-Otrin, M. P. McLenigan, D. C. Bisi, M. Gonzalez, and A. S. Levine Sequential binding of UV DNA damage binding factor and degradation of the p48 subunit as early events after UV irradiation Nucleic Acids Res., June 1, 2002; 30(11): 2588 - 2598. [Abstract] [Full Text] [PDF] |
||||
![]() |
V. Otrin, M McLenigan, M Takao, A. Levine, and M Protic Translocation of a UV-damaged DNA binding protein into a tight association with chromatin after treatment of mammalian cells with UV light J. Cell Sci., January 5, 1997; 110(10): 1159 - 1168. [Abstract] [PDF] |
||||

