Recombinant aryl hydrocarbon receptors for bioassay of aryl hydrocarbon receptor ligands in transgenic tobacco plants

• Published in: Plant biotechnology journal Vol. 7; no. 2; p. 119
• Main Authors: Kodama, Susumu, Okada, Kumiko, Akimoto, Keiko, Inui, Hideyuki, Ohkawa, Hideo
• Format: Journal Article
• Language: English
• Published: England 01-02-2009
• Subjects: Animals; Bacterial Proteins - genetics; Bacterial Proteins - metabolism; beta-Naphthoflavone - metabolism; Dioxins - metabolism; Gene Expression; Genes, Reporter; Indigo Carmine; Indoles - metabolism; Ligands; Methylcholanthrene - metabolism; Mice; Nicotiana - genetics; Nicotiana - metabolism; Plants, Genetically Modified - genetics; Plants, Genetically Modified - metabolism; Promoter Regions, Genetic; Receptors, Aryl Hydrocarbon - genetics; Receptors, Aryl Hydrocarbon - metabolism; Recombinant Proteins - genetics; Recombinant Proteins - metabolism; Saccharomyces cerevisiae - genetics; Saccharomyces cerevisiae - metabolism; Serine Endopeptidases - genetics; Serine Endopeptidases - metabolism; Transcription Factors - genetics; Transcription Factors - metabolism
• ISSN: 1467-7652
• DOI: 10.1111/j.1467-7652.2008.00378.x

Dioxin residues widely contaminate soil and agricultural products at low concentrations and may accumulate in organisms at the top of food chains owing to their physicochemical properties. In this study, we have developed novel, dioxin-inducible, reporter gene expression systems regulated by recombinant aryl hydrocarbon receptors (AhRs). The recombinant AhRs, referred to as XDVs, consist of the DNA-binding domain of the bacterial repressor protein LexA, a 90-kDa heat shock protein- and ligand-binding regulatory domain from mouse AhR, and the transactivation domain of herpes simplex virus regulatory protein VP16. Transgenic tobacco plants carrying XDVs absorb various AhR ligands, including 3-methylcholanthrene, beta-naphthoflavone and indigo from solid medium and vermiculite, and show dose- and time-dependent expression of the beta-glucuronidase reporter gene. The results clearly suggest that XDVs are functional transcription factors that respond to AhR ligands, and that the XDV-mediated reporter gene expression system is applicable to bioassays for dioxin residues in the environment.