Reduced Plasmodium infection in mosquitoes with 4.3kb SV
A negative association was found between the 4.3kb SV and the malaria
parasite infection, with mosquitoes lacking the 4.3kb SV being more
commonly infected than those with the 4.3kb SV. We might speculate that
this is linked to 4.3kb SV-driven overexpression of CYP6P9a/bsince P450s could play a role in the mosquito response toPlasmodium invasion by participating in the production of nitric
oxide and other reactive oxygen radicals (Han et al., 2000; Luckhart et
al., 1998) helping to eliminate the parasite. Previous studies have
shown specific cytochrome P450s implicated in insecticide resistance are
also differentially expressed during malaria parasite invasion in
mosquitoes (Félix et al., 2010). For example, CYP6M2 andCYP6Z1 both highly expressed in pyrethroid resistant An.
gambiae mosquitoes (David et al., 2005; Müller et al., 2007) were also
highly overexpressed in response to Plasmodium infection (Félix
et al., 2010), suggesting an interaction between insecticide
detoxification and infection. The results obtained are the opposite of
what had been previously obtained with the GSTe2 119F resistant
markers, where an association was observed with the homozygote 119F/F
genotype being more associated with the Plasmodium infection at
the oocyst and sporozoite stage (Tchouakui, Chiang, et al., 2019). These
preliminary results need further validation using experimental infection
studies as previously done with the kdr resistance mutations
(Ndiath et al., 2014) to decipher the impact of P450-based resistance on
malaria transmission.