Phytoremediation of the herbicides atrazine and metolachlor by transgenic rice plants expressing human CYP1A1, CYP2B6, and CYP2C19.
This study evaluated the expression of human cytochrome P450 genes CYP1A1, CYP2B6, and CYP2C19 in rice plants (Oryza sativa cv. Nipponbare) introduced using the plasmid pIKBACH. The transgenic rice plants (pIKBACH rice plants) became more tolerant toward various herbicides than nontransgenic Nipponbare rice plants. Rice plants expressing pIKBACH grown in soil showed tolerance to the herbicides atrazine, metolachlor, and norflurazon and to a mixture of the three herbicides. The degradation of atrazine and metolachlor by pIKBACH rice plants was evaluated to confirm the metabolic activity of the introduced P450s. Although both pIKBACH and nontransgenic Nipponbare rice plants could decrease the amounts of the herbicides in plant tissue and culture medium, pIKBACH rice plants removed greater amounts in greenhouse experiments. The ability of pIKBACH rice plants to remove atrazine and metolachlor from soil was confirmed in large-scale experiments. The metabolism of herbicides by pIKBACH rice plants was enhanced by the introduced P450 species. Assuming that public and commercial acceptance is forthcoming, pIKBACH rice plants may become useful tools for the breeding of herbicide-tolerant crops and for phytoremediation of environmental pollution by organic chemicals.
Kawahigashi
Hiroyuki
H
Plant Biotechnology Department, National Institute of Agrobiological Sciences, Tsukuba, Ibaraki 305-8602, Japan. shiwak@affrc.go.jp
Hirose
Sakiko
S
Ohkawa
Hideo
H
Ohkawa
Yasunobu
Y
D000081:Acetamides / Q000494:pharmacology*; D001189:Aryl Hydrocarbon Hydroxylases / Q000235:genetics; D001280:Atrazine / Q000494:pharmacology*; D019363:Cytochrome P-450 CYP1A1 / Q000235:genetics; D065702:Cytochrome P-450 CYP2B6; D065731:Cytochrome P-450 CYP2C19; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics*; D015870:Gene Expression; D006540:Herbicides / Q000032:analysis / Q000494:pharmacology*; D006899:Mixed Function Oxygenases / Q000235:genetics; D012275:Oryza / Q000737:chemistry / Q000187:drug effects / Q000235:genetics*; D010089:Oxidoreductases, N-Demethylating / Q000235:genetics; D030821:Plants, Genetically Modified / Q000187:drug effects / Q000235:genetics*; D012987:Soil / Q000032:analysis
D000081:Acetamides; D006540:Herbicides; D012987:Soil; D003577:Cytochrome P-450 Enzyme System; D006899:Mixed Function Oxygenases; D001189:Aryl Hydrocarbon Hydroxylases; C585599:CYP2B6 protein, human; C045793:CYP2C19 protein, human; D019363:Cytochrome P-450 CYP1A1; D065702:Cytochrome P-450 CYP2B6; D065731:Cytochrome P-450 CYP2C19; D010089:Oxidoreductases, N-Demethylating; D001280:Atrazine; C051786:metolachlor