Resistance of a soybean cell line to oxyfluorfen by overproduction of mitochondrial protoporphyrinogen oxidase.
Resistance of a soybean cell line to oxyfluorfen by overproduction of mitochondrial protoporphyrinogen oxidase.
复制标题
大豆细胞系因线粒体原卟啉原氧化酶过量产生而对乙氧氟草醚产生抗性。
DOI：
10.1002/ps.357
复制
发表时间：
2001
影响因子：
4.1
通讯作者：
H. Matsumoto
中科院分区：
文献类型：
--
作者：
E. Warabi;K. Usui;Yoshiyuki Tanaka;H. Matsumoto
二苯醚除草剂乙氧氟草醚（2-氯-4-三氟甲基苯基 3-乙氧基-4-硝基苯基醚）可抑制原卟啉原氧化酶 (Protox)，该酶催化原卟啉原 IX (Protogen) 氧化为原卟啉 IX (Proto IX)，这是叶绿素和血红素生物合成共同途径的最后一步。我们通过逐步选择的方法筛选出抗乙氧氟草醚的大豆细胞系，并对其耐药机制进行了研究。在10(-7)M乙氧氟草醚浓度下，在抗性细胞中没有观察到生长抑制，在该浓度下正常细胞无法存活。虽然乙氧氟草醚对总可提取原氧化酶的抑制程度在两种细胞类型中相同，但未处理的耐药细胞的线粒体部分中的酶活性比正常细胞高约九倍。 Northern 分析显示，耐药细胞中线粒体 Protox mRNA 的浓度远高于正常细胞。乙氧氟草醚的吸收和代谢分解没有差异。耐药细胞的生长对恶二唑[5-叔丁基-3-(2,4-二氯-5-异丙氧基苯基)-1,3,4-恶二唑-2-(3H)-一]也不敏感，恶二唑是Protox抑制剂的另一种化学类型。因此，所选大豆细胞系对乙氧氟草醚的抗性可能主要是由于线粒体Protox的过量产生。
The diphenyl ether herbicide oxyfluorfen (2-chloro-4-trifluoromethylphenyl 3-ethoxy-4-nitrophenyl ether) inhibits protoporphyrinogen oxidase (Protox) which catalyzes the oxidation of protoporphyrinogen IX (Protogen) to protoporphyrin IX (Proto IX), the last step of the common pathway to chlorophyll and haeme biosynthesis. We have selected an oxyfluorfen-resistant soybean cell line by stepwise selection methods, and the resistance mechanism has been investigated. No growth inhibition was observed in resistant cells at a concentration of 10(-7) M oxyfluorfen, a concentration at which normal cells did not survive. While the degree of inhibition of total extractable Protox by oxyfluorfen was the same in both cell types, the enzyme activity in the mitochondrial fraction from non-treated resistant cells was about nine-fold higher than that from normal cells. Northern analysis of mitochondrial Protox revealed that the concentration of mitochondrial Protox mRNA was much higher in resistant cells than that in normal cells. There were no differences in the absorption and metabolic breakdown of oxyfluorfen. The growth of resistant cells was also insensitive to oxadiazon [5-tert-butyl-3-(2,4-dichloro-5-isopropoxyphenyl)-1,3,4-oxadiazol-2-(3H)- one], the other chemical class of Protox inhibitor. Therefore, the resistance of the selected soybean cell line to oxyfluorfen is probably mainly due to the overproduction of mitochondrial Protox.