Polymorphism and Distribution of Ace Gene Involved in the Resistance of Musca Domestica to Organophosphates in Guizhou Province of China

Abstract

Acetylcholinesterase is the primary target of organophosphates (OPs) and carbamates in insects. As gene mutation has been verified as an important mechanism of insecticide resistance in insects, in this study, we investigated the status of OPs resistance and the polymorphism of ace gene (that encodes acetylcholinesterase) in housefly (Musca domestica L) field populations in Guizhou Province, China. Bioassays showed that the houseflies had 142.16–303.54-fold resistance to dichlorvos (DDVP) and 122.13–363.98-fold resistance to temephos. Molecular analysis revealed resistance-causing mutations of ace gene at loci of 260, 342 and 407 in the housefly populations, with a total frequency of 55%, 100% and 94%, respectively. In addition, 11 combinations of ace mutation were observed across the detected populations. The most frequently detected combination was L/V+A/V+Y, followed by L+A+Y and L/V+A+Y. No significant relationship was found between single mutation/combination mutations and DDVP resistance. These results indicate that the OPs resistance is prevalent among the housefly populations in Guizhou Province, with a similar pattern of allele mutation of ace across China. The target resistance can not fully account for the resistance of houseflies to OPs in Guizhou.

Single and Combined Mutations of Acetylcholinesterase Gene Giving Resistance to Pirimiphos-Methyl in Musca domestica Slaughterhouse Populations

“…In addition, the homozygous genotypes of these wild type amino acids were detected in field populations, except for the Riyadh population, where Val/Val and Gly/Gly, at positions 260 and 342, respectively, were not detected ( Table 3 ). As in other worldwide house fly populations, Val/Val homozygotes at the 342 position were not recovered [ 4 , 6 , 16 , 44 ]. Based on previous studies and this study, the three mutations at positions 260, 342, and 407 confer different levels of insecticide insensitivity in house flies [ 4 , 15 , 17 , 18 , 48 , 49 ].…”

“…Walsh et al [ 15 ] reported that house fly strain 77M, possessing Leu + Ala + Tyr combination, showed 48-fold DDVP resistance compared with the wild type. This combination was also frequently detected in house fly field populations in the USA, Turkey, Japan, Kazakhstan, and China [ 4 , 6 , 16 , 17 , 35 , 48 ]. Among the 13 heterogeneous combinations, Val/Leu + Ala/Val + Tyr and Leu + Ala + Phe/Tyr were well represented in the surveyed regions.…”

“…Insecticide chemicals, which come in a variety of formulations and treatment techniques, are the greatest options for quick, inexpensive, and practical house fly management. In several countries, organophosphate (OP) insecticides have been used extensively to control house flies [ 4 , 5 , 6 ]. In Saudi Arabia, the extensive use of insecticides for a long time has led to the development of resistance in house fly populations [ 7 , 8 , 9 , 10 ].…”

“…Resistance to OP insecticides has been linked to metabolic resistance via the increased activity of detoxifying enzymes and/or acetylcholinesterase (AChE) insensitivity [ 6 , 11 ]. Carbamate and OP insecticides are structural analogs of acetylcholine, and they can inactivate the insect AChE enzyme, leading to an excess of acetylcholine at cholinergic synapses, eventually causing paralysis and death of insects [ 12 , 13 ].…”

“…Carbamate and OP insecticides are structural analogs of acetylcholine, and they can inactivate the insect AChE enzyme, leading to an excess of acetylcholine at cholinergic synapses, eventually causing paralysis and death of insects [ 12 , 13 ]. To overcome the sensitivity of AChE to OP and carbamate insecticides, house flies develop resistance by creating mutations in the acetylcholinesterase ( Ace ) gene that produces AChE insensitivity to insecticides [ 6 , 14 , 15 , 16 ]. Currently, seven nonsynonymous mutations (A/G-495 ˃ Ile162Met, G/C-787 ˃ Val260Leu, C/T-929 ˃ Thr310Met, G/T-946 ˃ Ala316Ser, G/C/T-1025 ˃ Gly342Ala/Val, T/A-1220 ˃ Phe407Tyr, and G/C-1334 ˃ Gly445Ala), existing singly or in combination and associated with OPs resistance, have been identified in the house fly Ace gene [ 5 , 15 , 17 , 18 ].…”