Li Peihan, Xiang Taihe, Xie Jun, Feng Ting, Lu Wenyi
College of Life and Environment Sciences, Hangzhou Normal University, Hangzhou 310036, Zhejiang, China.
Sheng Wu Gong Cheng Xue Bao. 2012 Oct;28(10):1195-204.
CYP2E1 enzyme encoded by cyp2e1 gene plays an important role in metabolism of heterogeneous organics in mammalian liver cells. The transgenic plant with cyp2e1 can metabolize various low molecular weight organic pollutants. However, it is unclear the mechanism of expression control of cyp2e1 in transgenic plant. In this study, plasmid pSLD50-6 with cyp2e1 and pKH200 with gus as control were transformed into Agrobacterium tumefaciens GV3101 separately. Then, the cyp2e1 or gus genes were transferred into tobacco (Nicotiana tabacum) and the transgenic plants were regenerated via Agrobacterium tumefaciens method. Real-time quantitative PCR (qRT-PCR) was used to analyze the cyp2e1 gene expression. The expression of cyp2e1 in transgenic tobacco with cyp2e1 decreased obviously treated by ethyl alcohol and reduced slightly by benzene and toluene, while it enhanced by acetone, formaldehyde and oxygen deficit in different levels. In addition, the gene expression of NADPH-P450 oxidoreductase and cytochrome b5 enzyme in the transgenic tobacco with cyp2e1 were increased significantly treated by benzene, which showed that NADPH-P450 oxidoreductase and cytochrome b5 enzyme in transgenic tobacco have relation with CYP2E1 detoxication process. It suggested that the NADPH-P450 oxidoreductase and cytochrome b5 enzyme in transgenic plant formed the requirement in mammalian and participated in the electron transport chain of CYP2E1 enzyme catalytic process.
由cyp2e1基因编码的CYP2E1酶在哺乳动物肝细胞中异源有机物的代谢过程中发挥着重要作用。携带cyp2e1的转基因植物能够代谢多种低分子量有机污染物。然而,目前尚不清楚cyp2e1在转基因植物中的表达调控机制。在本研究中,分别将携带cyp2e1的质粒pSLD50 - 6和作为对照的携带gus的pKH200转化到根癌农杆菌GV3101中。然后,通过根癌农杆菌介导法将cyp2e1或gus基因导入烟草(Nicotiana tabacum)并再生出转基因植株。采用实时定量PCR(qRT-PCR)分析cyp2e1基因的表达情况。携带cyp2e1的转基因烟草中,cyp2e1的表达在乙醇处理后明显下降,在苯和甲苯处理后略有降低,而在丙酮、甲醛和缺氧处理后则有不同程度的升高。此外,携带cyp2e1的转基因烟草在苯处理后,NADPH - P450氧化还原酶和细胞色素b5酶的基因表达显著增加,这表明转基因烟草中的NADPH - P450氧化还原酶和细胞色素b5酶与CYP2E1解毒过程有关。这表明转基因植物中的NADPH - P450氧化还原酶和细胞色素b5酶满足了哺乳动物中的需求,并参与了CYP2E1酶催化过程的电子传递链。