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Updated: Oct 3, 2025

Visualization of UV-induced Replication Intermediates in E. coli using Two-dimensional Agarose-gel Analysis
Published on: December 21, 2010
Replication-related genes are upregulated in XP-A cells after UV-C irradiation
Seiji Takeuchi1, Toshiro Matsuda2, Mariko Tsujimoto1
1Division of Dermatology, Department of Internal Related, Kobe University Graduate School of Medicine, Japan.
Background:
Xeroderma pigmentosum (XP) is hereditary disorder characterized by photosensitivity, predisposition to skin cancers of sun-exposed body sites and progressive neurologic symptoms in some cases. Cells from XP patients show higher sensitivity to ultraviolet radiation (UV) than normal cells.
Objective:
We aimed to ascertain the genes differentially regulated in XP complementation group A (XP-A) cells after UV irradiation.
Methods:
XP-A cells were harvested at 4 or 12 h after a single exposure to low-dose UV-C radiation and subjected to transcriptome analysis by microarray.
Results:
The number of genes with significantly altered expression (≥2-fold difference) at 12 h was markedly higher in XP-A cells than that in normal cells, suggesting that the number of altered genes could be correlated to the amount of DNA damage.
Conclusion:
We recently reported that mitotic genes are induced in normal human fibroblasts after UV-C exposure, and similar results were observed in XP-A cells as normal cells. In addition, a majority of replication-related genes were significantly upregulated in XP-A cells, whereas no such expression pattern was observed in the normal control cells. Collectively, these results indicate that the XPA protein can transcriptionally inhibit the series of replication-related genes, and could possibly regulate replication and/or re-replication after UV irradiation.
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