Rice-arsenate interactions in hydroponics: whole genome transcriptional analysis.
Rice (Oryza sativa) varieties that are arsenate-tolerant (Bala) and -sensitive (Azucena) were used to conduct a transcriptome analysis of the response of rice seedlings to sodium arsenate (AsV) in hydroponic solution. RNA extracted from the roots of three replicate experiments of plants grown for 1 week in phosphate-free nutrient with or without 13.3 muM AsV was used to challenge the Affymetrix (52K) GeneChip Rice Genome array. A total of 576 probe sets were significantly up-regulated at least 2-fold in both varieties, whereas 622 were down-regulated. Ontological classification is presented. As expected, a large number of transcription factors, stress proteins, and transporters demonstrated differential expression. Striking is the lack of response of classic oxidative stress-responsive genes or phytochelatin synthases/synthatases. However, the large number of responses from genes involved in glutathione synthesis, metabolism, and transport suggests that glutathione conjugation and arsenate methylation may be important biochemical responses to arsenate challenge. In this report, no attempt is made to dissect differences in the response of the tolerant and sensitive variety, but analysis in a companion article will link gene expression to the known tolerance loci available in the BalaxAzucena mapping population.
Norton
Gareth J
GJ
Department of Plant and Soil Science, Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 3UU, UK. g.norton@abdn.ac.uk
Lou-Hing
Daniel E
DE
Meharg
Andrew A
AA
Price
Adam H
AH
D001149:Arsenates / Q000378:metabolism / Q000494:pharmacology*; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D018745:Genome, Plant / Q000187:drug effects*; D005982:Glutathione Transferase / Q000235:genetics; D006360:Heat-Shock Proteins / Q000235:genetics; D018527:Hydroponics; D008780:Methyltransferases / Q000235:genetics; D008969:Molecular Sequence Data; D020411:Oligonucleotide Array Sequence Analysis; D012275:Oryza / Q000187:drug effects* / Q000235:genetics* / Q000254:growth & development; D010544:Peroxidases / Q000235:genetics; D010940:Plant Proteins / Q000235:genetics; D018517:Plant Roots / Q000254:growth & development; D036226:Seedlings / Q000187:drug effects / Q000235:genetics / Q000254:growth & development; D014158:Transcription, Genetic / Q000187:drug effects*
D001149:Arsenates; D006360:Heat-Shock Proteins; D010940:Plant Proteins; C095825:expansin protein, plant; C009277:sodium arsenate; D010544:Peroxidases; D008780:Methyltransferases; D005982:Glutathione Transferase; C025657:arsenic acid