title: Resistance to herbicides caused by single amino acid mutations in acetyl-CoA carboxylase in resistant populations of grassy weeds.
abstract: Eleven spontaneous mutations of acetyl-CoA carboxylase have been identified in many herbicide-resistant populations of 42 species of grassy weeds, hampering application of aryloxyphenoxypropionate, cyclohexadione and phenylpyrazoline herbicides in agriculture. IC(50)  shifts (resistance indices) caused by herbicide-resistant mutations were determined using a recombinant yeast system that allows comparison of the effects of single amino acid mutations in the same biochemical background, avoiding the complexity inherent in the in planta experiments. The effect of six mutations on the sensitivity of acetyl-CoA carboxylase to nine herbicides representing the three chemical classes was studied. A combination of partially overlapping binding sites of the three classes of herbicides and the structure of their variable parts explains cross-resistance among and between the three classes of inhibitors, as well as differences in their specificity. Some degree of resistance was detected for 51 of 54 herbicide/mutation combinations. Introduction of new herbicides targeting acetyl-CoA carboxylase will depend on their ability to overcome the high degree of cross-resistance already existing in weed populations.
authors.affiliation: Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL, 60637, USA.
authors.forename: SoRi
authors.initials: S
authors.lastname: Jang
authors.affiliation: Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL, 60637, USA.
authors.forename: Jasmina
authors.initials: J
authors.lastname: Marjanovic
authors.affiliation: Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL, 60637, USA.
authors.forename: Piotr
authors.initials: P
authors.lastname: Gornicki
mesh_terms: D000103:Acetyl-CoA Carboxylase / Q000737:chemistry / Q000235:genetics*; D000383:Agriculture / Q000379:methods; D001665:Binding Sites; D053209:Herbicide Resistance / Q000235:genetics*; D006540:Herbicides / Q000494:pharmacology*; D008958:Models, Molecular; D009154:Mutation; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics*; D057685:Plant Weeds / Q000187:drug effects / Q000235:genetics*; D017434:Protein Structure, Tertiary
chemical_list: D006540:Herbicides; D010940:Plant Proteins; D000103:Acetyl-CoA Carboxylase