Related Experiment Videos
Systemic plant signal triggers genome instability.
Jody Filkowski1, Allan Yeoman, Olga Kovalchuk
1Department of Biological Sciences, University of Lethbridge, Lethbridge, Alta, Canada T1K 3M4.
The Plant Journal : for Cell and Molecular Biology
|April 1, 2004
Summary
Free radicals, generated by UVC or rose Bengal, induce homologous recombination (HR) in tobacco plants locally and systemically. Radical scavenging with NAC reduces this effect, suggesting free radicals mediate the systemic HR signal.
Area of Science:
- Plant molecular biology
- Genetics
- Biochemistry
Background:
- Viral infection in tobacco plants induces homologous recombination (HR) both locally and systemically.
- The mechanism and signaling pathway for systemic HR induction remain unclear.
Purpose of the Study:
- To investigate the potential involvement of free radicals in the systemic induction of homologous recombination (HR).
- To elucidate the signaling mechanism underlying systemic HR.
Main Methods:
- Treatment of tobacco plants with radical-generating agents (UVC, rose Bengal).
- Grafting experiments to assess systemic signal transmission.
- Analysis of transgenic plants (NahG) with altered salicylic acid levels.
- Assessment of radical scavenging effects using N-acetyl-l-cysteine (NAC).
Main Results:
- UVC and rose Bengal treatments significantly increased HR in both local and systemic tissues.
- Grafting experiments confirmed the transmission of a systemic signal inducing HR.
- NahG plants showed similar HR induction patterns, suggesting salicylic acid is not essential.
- NAC pre-treatment reduced HR induction and decreased oxidized organic compounds, indicating a role for free radicals.
Conclusions:
- Free radical production is implicated in the generation and/or maintenance of the systemic signal for homologous recombination.
- This suggests a novel adaptive mechanism where DNA-damaging agents trigger genomic flexibility via free radical signaling.