Cytochrome P450 BsCYP99A44 and BsCYP704A177 Confer Metabolic Resistance to ALS Herbicides in Beckmannia syzigachne

Abstract

Beckmannia syzigachne is a noxious grassy weed that infests wheat fields in China. Previously, we identified that mesosulfuron-methyl resistance in a B. syzigachne population (R, SD04) was conferred by non-target resistance, such as cytochrome P450 mixed-function oxidases (P450s)-based metabolism. RNA sequencing and real-time PCR (qRT-PCR) were used to discover potential P450s-resistant-related genes. Five cytochrome P450s (CYP704A177, CYP96B84, CYP71D7, CYP93A1, and CYP99A44) were found to be highly expressed in R plants. In this study, CYP99A44 and CYP704A177 were cloned from B. syzigachne and transferred into Arabidopsis thaliana to test the sensitivity of Arabidopsis with and without P450s genes to mesosulfuron-methyl and other acetolactate synthase (ALS)-inhibiting herbicides. Transgenic Arabidopsis overexpressing CYP99A44 became resistant to the sulfonylurea herbicide mesosulfuron-methyl, but showed no resistance to pyroxsulam, imazethapyr, flucarbazone, and bispyribac-sodium. Notably, those overexpressing CYP704A177 showed resistance to pyroxsulam and bispyribac-sodium, but not to mesosulfuron-methyl, imazethapyr, and flucarbazone. These results indicated that B. syzigachne and transgenic Arabidopsis displayed different cross-resistance patterns to ALS-inhibiting herbicides. Subcellular localization revealed that CYP99A44 and CYP704A177 protein were located in the endoplasmic reticulum. Furthermore, these results clearly indicated that CYP99A44-mediated mesosulfuron-methyl resistance in B. syzigachne and CYP704A177 may be involved in B. syzigachne cross-resistance to pyroxsulam and bispyribac-sodium.

Multiple Metabolic Enzymes Can Be Involved in Cross-Resistance to 4-Hydroxyphenylpyruvate-Dioxygenase-Inhibiting Herbicides in Wild Radish

“…phyllopogon confers resistance to ACCase-inhibiting herbicide diclofop-methyl . Apart from CYP709 , a CYP704A177 gene from Beckmannia syzigachne has recently been identified to confer resistance to ALS-inhibiting herbicides pyroxsulam and bispyribac-sodium . Apparently, all of these currently identified CYP709 and CYP704 offer a narrow resistance spectrum relative to CYP81As.…”

Target-Site and Metabolic Resistance Mechanisms to Penoxsulam in Late Watergrass (Echinochloa phyllopogon) in China

“…21,39 The current understanding of metabolic resistance mediated by P450 is comprehensive, with specific genes identified to produce metabolic resistance to certain herbicide ALS and ACCase inhibitors. 2,23,26,40 Within the R population featuring the three metabolic inhibitors, changes in sensitivity to penoxsulam suggest that metabolism may be related to herbicide resistance. Metabolic resistance in weeds to herbicides is driven by diverse metabolic enzymes, including P450s, GSTs, GTs, and ABC transporters.…”

“…40,48 In China, CYP81A68 metabolizes penoxsulam in resistant Echinochloa colonum, 23 while CYP706C56 metabolizes mesosulfuron-methyl in resistant A. aequalis. 24 Bai et al found that two CYP genes, CYP99A44 and CYP704A177, 26 play important roles in the metabolic resistance of Beckmannia syzigachne to ALS inhibitors. Our study highlighted nine significantly upregulated P450 genes in the resistant population under the three herbicide treatments with different mechanisms of action.…”

“…This suggests that the R population may develop mechanisms to confer herbicide resistance against different modes of action, especially for herbicides that are induced similarly to those previously encountered by the population. These mechanisms are typically related to herbicide metabolism. , The current understanding of metabolic resistance mediated by P450 is comprehensive, with specific genes identified to produce metabolic resistance to certain herbicide ALS and ACCase inhibitors. ,,, Within the R population featuring the three metabolic inhibitors, changes in sensitivity to penoxsulam suggest that metabolism may be related to herbicide resistance.…”

Degradation strategies of pesticide residue: From chemicals to synthetic biology

“…(2) Affecting the ETC, for example, dinoseb and 2,6-dichlorobenzamide [ 29 ]. (3) Inhibiting critical biosynthesis such as cytochromes (e.g., pyrazlynate), amino acids (e.g., glyphosate and sulfonylureas), fatty acids (e.g., aryloxyphenoxypropionates) [ 30 , 31 ] (4) Preventing cell division (e.g., asulam). and growth (e.g., benzoylprop-ethyl) [ 32 , 33 ].…”