Microarray analysis of Arabidopsis plants in response to allelochemical l-DOPA

Abstract

Velvetbean (Mucuna pruriens) plants impede the growth of neighboring plants. One compound, 3-(3',4'-dihydroxyphenyl)-L-alanine (L-DOPA), is responsible for the allelopathic capacity of velvetbean. This compound is an active allelochemical that decreases root growth of several plant species. In mammals, L-DOPA is a well-known therapeutic agent for the symptomatic relief of Parkinson's disease. However, its mode of action in plants is still not well understood. To address such issues, gene expression in Arabidopsis thaliana plants, which had been exposed to L-DOPA, was analyzed using DNA microarrays. After 6 h of L-DOPA exposure, the expression of 110 genes was significantly upregulated, and the expression of 69 genes was significantly downregulated. These induced genes can be divided into different functional categories, mainly on the basis of subcellular localization, metabolism, and proteins with a binding function or cofactor requirement. Based on these results, we suggest that L-DOPA acts by two mechanisms: it influences amino acid metabolism and deregulates metal homeostasis, especially that of iron, which is required for the fundamental biological processes of all organisms.

The role of L-DOPA in plants

“…The authors suggested that the mode of action of L-DOPA may be related to changes in amino acid metabolism and iron homeostasis, important for many fundamental biological processes such as photosynthesis. 40 Additionally, L-DOPA also seems to mimic amino acid analogs, with subsequent incorporation into proteins. 26 In fact, the binding of L-DOPA to tyrosyl and phenylalanyltRNA synthetases has been observed in bacterial and prokaryotic-eukaryotic cells, respectively, 41 including mammalian cells in vitro.…”

Transcriptomic evaluation of the enhanced plant growth-inhibitory activity caused by derivatization of <i>cis</i>-cinnamic acid

“…13,14) It has been used to monitor changes in transcript levels in response to various allelochemical stresses on a whole-genome scale. 9,15,16) Presently, new agrochemicals are required to control weed strains that are resistant to commercial herbicides, but evaluating promising chemical derivatives is labor intensive and time consuming. DNA microarray analysis is potentially an efficient and rapid tool for evaluating the bioactivities of chemical derivatives.…”

Root-specific induction of early auxin-responsive genes in Arabidopsis thaliana by cis-cinnamic acid

“…Quantitative real-time PCR (qRT-PCR) analysis was performed as described (Golisz et al 2011) to investigate the expression of particular genes in shoots and roots over time, and to validate our microarray data sets. Plants were treated with 20 µM cis-CA, 20 µM IAA, or nothing (control).…”

“…Guo et al (2011) identified two cis-CA-upregulated Arabidopsis genes, MLPL1 (AT2G01520) and MLPL2 (AT2G01530). DNA microarray analysis could serve as an effective tool to investigate the mode of action of cis-CA, considering that it has been used to monitor changes in response to other allelochemical stresses in the transcription state of individual Arabidopsis genes on a whole-genome scale (Baerson et al 2005;Golisz et al 2011). In the present study, we reveal for the first time the Arabidopsis genes upregulated by exogenous cis-CA, using a DNA microarray and Gene Ontology enrichment analysis.…”