The Rad17 homologue of Arabidopsis is involved in the regulation of DNA damage repair and homologous recombination
Article first published online: 29 APR 2004
The Plant Journal
Volume 38, Issue 6, pages 954–968, June 2004
How to Cite
Heitzeberg, F., Chen, I.-P., Hartung, F., Orel, N., Angelis, K. J. and Puchta, H. (2004), The Rad17 homologue of Arabidopsis is involved in the regulation of DNA damage repair and homologous recombination. The Plant Journal, 38: 954–968. doi: 10.1111/j.1365-313X.2004.02097.x
- Issue published online: 29 APR 2004
- Article first published online: 29 APR 2004
- Received 19 January 2004; revised 27 February 2004; accepted 8 March 2004.
- double-strand break repair;
- comet assay
Rad17 is involved in DNA checkpoint control in yeast and human cells. A homologue of this gene as well as other genes of the pathway (the 9-1-1 complex) are present in Arabidopsis and share conserved sequence domains with their yeast and human counterparts. DNA-damaging agents induce AtRAD17 transcriptionally. AtRAD17 mutants show increased sensitivity to the DNA-damaging chemicals bleomycin and mitomycin C (MMC), which can be reversed by complementation, suggesting that the loss of function of Rad17 disturbs DNA repair in plant cells. Our results are further confirmed by the phenotype of a mutant of the 9-1-1 complex (Rad9), which is also sensitive to the same chemicals. AtRAD9 and AtRAD17 seem to be epistatic as the double mutant is not more sensitive to the chemicals than the single mutants. The mutants show a delay in the general repair of double-strand breaks (DSBs). However, frequencies of intrachromosomal homologous recombination (HR) are enhanced. Nevertheless, the mutants are proficient for a further induction of HR by genotoxic stresses. Our results indicate that a mutant Rad17 pathway is associated with a general deregulation of DNA repair, which seems to be correlated with a deficiency in non-homologous DSB repair.