Abstract
Both insects and mammals all exhibit a daily fluctuation of susceptibility to chemicals at different times of the day. However, this phenomenon has not been further studied in the house fly (Musca domestica L.) and a better understanding of the house fly on chronobiology should be useful for controlling this widespread disease vector. Here we explored diel time-of-day variations in insecticide susceptibility, enzyme activities, and xenobiotic-metabolizing enzyme gene expressions. The house fly was most tolerant to beta-cypermethrin in the late photophase at Zeitgeber time (ZT) 8 and 12 [i.e., 8 and 12 h after light is present in the light-dark cycle (LD)]. The activities of cytochrome P450, GST, and CarE enzymes were determined in the house flies collected at various time, indicating that rhythms occur in P450 and CarE activities. Subsequently, we observed diel rhythmic expression levels of detoxifying genes, and CYP6D1 and MdαE7 displayed similar expression patterns with enzyme activities in LD conditions, respectively. No diel rhythm was observed for CYP6D3 expression. These data demonstrated a diel rhythm of metabolic detoxification enzymes and insecticide susceptibility in M. domestica. In the future, the time-of-day insecticide efficacy could be considered into the management of the house fly.
Highlights
Multiple factors, including physical, chemical, and physiological aspects, may influence insecticide toxicity (Pszczolkowski et al, 2004)
To understand whether the daily variations in beta-cypermethrin sensitivity were due to the physiological effects of detoxifying enzymes, we investigated the diurnal variations in beta-cypermethrin susceptibility, metabolic enzyme activities, and several detoxification-related gene expressions in M. domestica across 24 h under environmental light:dark (LD) conditions
Differences in house fly mortality of those exposed to LC50 1.45 μg/cm2 betacypermethrin at different times of day indicate that the house flies possessed rhythmic susceptibility to this insecticide (Figure 1)
Summary
Multiple factors, including physical, chemical, and physiological aspects, may influence insecticide toxicity (Pszczolkowski et al, 2004). Synthetic pyrethroids targeting a voltage-sensitive sodium channel gene (Vssc) remain the most widely used insecticides against house flies due to their effectiveness and safety Both targetsite Vssc insensitivity and detoxification changes were two crucial pyrethroid resistance mechanisms reported in house flies (Liu et al, 2006; Zhang et al, 2007, 2010; Scott, 2017). Time of dayspecific changes in GST activities were involved in DDT and deltamethrin resistance in the malaria A. gambie (Balmert et al, 2014). Based on these studies, it was worth better understanding diel rhythms of detoxification mechanisms in insecticide toxicity against the house fly. To understand whether the daily variations in beta-cypermethrin sensitivity were due to the physiological effects of detoxifying enzymes, we investigated the diurnal variations in beta-cypermethrin susceptibility, metabolic enzyme activities, and several detoxification-related gene expressions in M. domestica across 24 h under environmental light:dark (LD) conditions
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
