title: Variable Levels of Glutathione S-Transferases Are Responsible for the Differential Tolerance to Metolachlor between Maize (Zea mays) Shoots and Roots.
abstract: Glutathione S-transferases (GSTs) play important roles in herbicide tolerance. However, studies on GST function in herbicide tolerance among plant tissues are still lacking. To explore the mechanism of metolachlor tolerance difference between maize shoots and roots, the effects of metolachlor on growth, GST activity, and the expression of the entire GST gene family were investigated. It was found that this differential tolerance to metolachlor was correlated with contrasting GST activity between the two tissues and can be eliminated by a GST inhibitor. An in vitro metolachlor-glutathione conjugation assay confirmed that the transformation of metolachlor is 2-fold faster in roots than in shoots. The expression analysis of the GST gene family revealed that most GST genes are expressed much higher in roots than shoots, both in control and in metolachlor-treated plants. Taken together, higher level expression of most GST genes, leading to higher GST activity and faster herbicide transformation, appears to be responsible for the higher tolerance to metolachlor of maize roots than shoots.
authors.affiliation: College of Science, China Agricultural University , No. 2 Yuan Ming Yuan West Road, Haidian District, Beijing 100193, People's Republic of China.
authors.forename: Dongzhi
authors.identifier: http://orcid.org/0000-0002-1245-9244
authors.initials: D
authors.lastname: Li
authors.affiliation: College of Science, China Agricultural University , No. 2 Yuan Ming Yuan West Road, Haidian District, Beijing 100193, People's Republic of China.
authors.forename: Li
authors.initials: L
authors.lastname: Xu
authors.affiliation: College of Science, China Agricultural University , No. 2 Yuan Ming Yuan West Road, Haidian District, Beijing 100193, People's Republic of China.
authors.forename: Sen
authors.initials: S
authors.lastname: Pang
authors.affiliation: Department of Economic Development, Jobs, Transport and Resources, AgriBio , 5 Ring Road, Bundoora, Victoria 3083, Australia.
authors.forename: Zhiqian
authors.initials: Z
authors.lastname: Liu
authors.affiliation: College of Science, China Agricultural University , No. 2 Yuan Ming Yuan West Road, Haidian District, Beijing 100193, People's Republic of China.
authors.forename: Kai
authors.initials: K
authors.lastname: Wang
authors.affiliation: College of Science, China Agricultural University , No. 2 Yuan Ming Yuan West Road, Haidian District, Beijing 100193, People's Republic of China.
authors.forename: Chengju
authors.initials: C
authors.lastname: Wang
mesh_terms: D000081:Acetamides / Q000378:metabolism*; D005982:Glutathione Transferase / Q000235:genetics / Q000378:metabolism*; D006540:Herbicides / Q000378:metabolism*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D018517:Plant Roots / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D018520:Plant Shoots / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D003313:Zea mays / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development / Q000378:metabolism
chemical_list: D000081:Acetamides; D006540:Herbicides; D010940:Plant Proteins; D005982:Glutathione Transferase; C051786:metolachlor
keywords: glutathione S-transferases; herbicide tolerance; maize; metolachlor; shoots and roots