Get 20M+ Full-Text Papers For Less Than $1.50/day. Start a 14-Day Trial for You or Your Team.

Learn More →

Xrcc1‐dependent and Ku‐dependent DNA double‐strand break repair kinetics in Arabidopsis plants

Xrcc1‐dependent and Ku‐dependent DNA double‐strand break repair kinetics in Arabidopsis plants Double‐strand breakage (DSB) of DNA involves loss of information on the two strands of the DNA fibre and thus cannot be repaired by simple copying of the complementary strand which is possible with single‐strand DNA damage. Homologous recombination (HR) can precisely repair DSB using another copy of the genome as template and non‐homologous recombination (NHR) permits repair of DSB with little or no dependence on DNA sequence homology. In addition to the well‐characterised Ku‐dependent non‐homologous end‐joining (NHEJ) pathway, much recent attention has been focused on Ku‐independent NHR. The complex interrelationships and regulation of NHR pathways remain poorly understood, even more so in the case of plants, and we present here an analysis of Ku‐dependent and Ku‐independent repair of DSB in Arabidopsis thaliana. We have characterised an Arabidopsis xrcc1 mutant and developed quantitative analysis of the kinetics of appearance and loss of γ‐H2AX foci as a tool to measure DSB repair in dividing root tip cells of γ‐irradiated plants in vivo. This approach has permitted determination of DSB repair kinetics in planta following a short pulse of γ‐irradiation, establishing the existence of a Ku‐independent, Xrcc1‐dependent DSB repair pathway. Furthermore, our data show a role for Ku80 during the first minutes post‐irradiation and that Xrcc1 also plays such a role, but only in the absence of Ku. The importance of Xrcc1 is, however, clearly visible at later times in the presence of Ku, showing that alternative end‐joining plays an important role in DSB repair even in the presence of active NHEJ. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png The Plant Journal Wiley

Xrcc1‐dependent and Ku‐dependent DNA double‐strand break repair kinetics in Arabidopsis plants

Loading next page...
 
/lp/wiley/xrcc1-dependent-and-ku-dependent-dna-double-strand-break-repair-7N3OXtD0Eh

References (73)

Publisher
Wiley
Copyright
Copyright © 2010 Wiley Subscription Services, Inc., A Wiley Company
ISSN
0960-7412
eISSN
1365-313X
DOI
10.1111/j.1365-313X.2010.04331.x
pmid
21070408
Publisher site
See Article on Publisher Site

Abstract

Double‐strand breakage (DSB) of DNA involves loss of information on the two strands of the DNA fibre and thus cannot be repaired by simple copying of the complementary strand which is possible with single‐strand DNA damage. Homologous recombination (HR) can precisely repair DSB using another copy of the genome as template and non‐homologous recombination (NHR) permits repair of DSB with little or no dependence on DNA sequence homology. In addition to the well‐characterised Ku‐dependent non‐homologous end‐joining (NHEJ) pathway, much recent attention has been focused on Ku‐independent NHR. The complex interrelationships and regulation of NHR pathways remain poorly understood, even more so in the case of plants, and we present here an analysis of Ku‐dependent and Ku‐independent repair of DSB in Arabidopsis thaliana. We have characterised an Arabidopsis xrcc1 mutant and developed quantitative analysis of the kinetics of appearance and loss of γ‐H2AX foci as a tool to measure DSB repair in dividing root tip cells of γ‐irradiated plants in vivo. This approach has permitted determination of DSB repair kinetics in planta following a short pulse of γ‐irradiation, establishing the existence of a Ku‐independent, Xrcc1‐dependent DSB repair pathway. Furthermore, our data show a role for Ku80 during the first minutes post‐irradiation and that Xrcc1 also plays such a role, but only in the absence of Ku. The importance of Xrcc1 is, however, clearly visible at later times in the presence of Ku, showing that alternative end‐joining plays an important role in DSB repair even in the presence of active NHEJ.

Journal

The Plant JournalWiley

Published: Oct 1, 2010

Keywords: ; ; ; ; ;

There are no references for this article.