Resistance to temephos in Anopheles stephensi larvae is associated with increased cytochrome P450 and α-esterase genes overexpression

The widespread use of synthetic insecticides has resulted in the development of insecticide resistance among disease mosquito vector. Resistance development involves several genes, including CYP450 and esterase family genes. In the current study, expression profiles of seven CYP450 genes namely, CYP9M10, CYP9J40, CYP6AA7, CYP9J34, CYTP450 B9, CYP6M2, CYP6Z2 and three esterase genes namely, esterase β1, alpha esterase, KM234962 were investigated in temephos resistant and susceptible in larvae. The third instar larvae of An. stephensi were subjected to insecticide selection with temephos (Tem Res) following the WHO protocol. Our results show CYP6M2,CYP6Z2 and alpha esterase genes are prominent in temephos resistant in larvae. We suggest that P450 genes and esterase genes, α-esterase and esterase β1 are mostly involved in temephos resistance in larval stage. These results suggest that metabolic resistance may be more prevalent in larval mosquito and play an important role in temephos resistance.