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Characterization of the plant homolog of Nijmegen breakage syndrome 1: Involvement in DNA repair and recombination

Department of Environmental Sciences, Faculty of Science, Ibaraki University, Bunkyo 2-1-1, Mito, Ibaraki 310-8512, Japan.
Biochemical and Biophysical Research Communications (Impact Factor: 2.28). 03/2007; 353(2):394-8. DOI: 10.1016/j.bbrc.2006.12.030
Source: PubMed

ABSTRACT The Nbs1 gene is known to code for a protein involved in the hereditary cancer-prone disease, Nijmegen breakage syndrome. This gene is conserved in animals and fungi, but no plant homolog is known. The work reported here describes a homolog of Nbs1 isolated from higher plants. The Nbs1 proteins from both Arabidopsis thaliana and Oryza sativa are smaller in size than animal or yeast Nbs1, but both contain the conserved Nbs1 domains such as the FHA/BRCT domain, the Mre11-binding domain, and the Atm-interacting domain in orientations similar to what is seen in animal Nbs1. The OsNbs1 protein interacted not only with plant Mre11, but also with animal Mre11. In plants, OsNbs1 mRNA expression was found to be higher in the shoot apex and young flower, and AtNbs1 expression increased when plants were exposed to 100 Gy of X-rays. These results suggest that plant Nbs1 could participate in a Rad50/Mre11/Nbs1 complex, and could be essential for the regulation of DNA recombination and DNA damage responses.

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    • "Therefore, we treated plants with c-irradiation that induces oxidative stress causing DNA single and doublestrand breaks as well as damaged bases. We compared the transcriptional profiles of GMI1 and of two repair genes known to be induced by c-irradiation (Garcia et al., 2003; Akutsu et al., 2007 "
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    • "3K - like kinase activity for their reversal . Activation of ATM is normally associated with activation of the MRE11 / RAD50 / NBS1 ( M / R / N ) complex , in which NBS1 is required for the signal transduction activity of the complex ( D ' Amours and Jackson , 2002 ; Falck et al . , 2005 ) . The plant homolog of NBS1 has recently been identified ( Akutsu et al . , 2007 ) , and its biological significance , including a possible role in meiosis , has been investigated ( Waterworth et al . , 2007 ) . Waterworth et al . established that the Arabidopsis NBS1 homolog is essential for cross - link repair ( demon - strating its functionality ) , but is not required for meiosis . Interestingly , the atm nbs1 d"
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