ARS | Publication request: Genomic Approaches to Understanding Allelochemical Modes of Action and Defenses Against Allelochemicals

Submitted to: International Allelopathy Congress
Publication Type: Proceedings
Publication Acceptance Date: June 18, 2005
Publication Date: September 23, 2005
Citation: Duke, S.O., Baerson, S.R., Pan, Z., Kagan, I., Sanchez-Moreiras, A., Reigosa, M.J., Pedrol-Bonjoch, N., Schulz, M. 2005. Genomic Approaches to Understanding Allelochemical Modes of Action and Defenses Against Allelochemicals. Harper, J.D.I., An, M., Wu, H., Kent, J.H., Editors. Charles Sturts University, Wagga Wagga, Australia. Proceedings of the 4th World Congress on Allelopathy. P. 107-113.

Technical Abstract: Little is known concerning the mode of action of allelochemicals or plant defense responses mounted against them. Theoretically, changes in the expression of genes encoding the primary target or other proteins in the same pathway should occur soon after phytotoxin exposure. Defense responses, such as the induction of genes involved in chemical detoxification, may occur later, depending on the nature of the chemosensors which presumably exist in plant cells. A battery of xenobiotic defense-associated genes are dramatically induced in Arabidopsis following exposure to an array of structurally-unrelated xenobiotics, including herbicides, allelochemicals, herbicide safeners, and environmental pollutants. These genes are unlikely to be strongly linked to the mode of action of a specific phytotoxin, but rather constitute a coordinately-controlled xenobiotic defense gene network. Transcriptional profiling experiments using microarrays are being conducted to examine the effects of various herbicides and natural phytotoxins on the Arabidopsis transcriptome. Approaches to analyzing microarray data to determine potential target sites for phytotoxins whose primary mode of action is unknown will be discussed.