Vgsc-interacting proteins are genetically associated with pyrethroid resistance in Aedes aegypti

Abstract

Association mapping of factors that condition pyrethroid resistance in Aedes aegypti has consistently identified genes in multiple functional groups. Toward better understanding of the mechanisms involved, we examined high throughput sequencing data (HTS) from two Aedes aegypti aegypti collections from Merida, Yucatan, Mexico treated with either permethrin or deltamethrin. Exome capture enrichment for coding regions and the AaegL5 annotation were used to identify genes statistically associated with resistance. The frequencies of single nucleotide polymorphisms (SNPs) were compared between resistant and susceptible mosquito pools using a contingency χ2 analysis. The -log10(χ2 p value) was calculated at each SNP site, with a weighted average determined from all sites in each gene. Genes with -log10(χ2 p value) ≥ 4.0 and present among all 3 treatment groups were subjected to gene set enrichment analysis (GSEA). We found that several functional groups were enriched compared to all coding genes. These categories were transport, signal transduction and metabolism, in order from highest to lowest statistical significance. Strikingly, 21 genes with demonstrated association to synaptic function were identified. In the high association group (n = 1,053 genes), several genes were identified that also genetically or physically interact with the voltage-gated sodium channel (VGSC). These genes were eg., CHARLATAN (CHL), a transcriptional regulator, several ankyrin-domain proteins, PUMILIO (PUM), a translational repressor, and NEDD4 (E3 ubiquitin-protein ligase). There were 13 genes that ranked among the top 10%: these included VGSC; CINGULIN, a predicted neuronal gap junction protein, and the aedine ortholog of NERVY (NVY), a transcriptional regulator. Silencing of CHL and NVY followed by standard permethrin bottle bioassays validated their association with permethrin resistance. Importantly, VGSC levels were also reduced about 50% in chl- or nvy-dsRNA treated mosquitoes. These results are consistent with the contribution of a variety of neuronal pathways to pyrethroid resistance in Ae. aegypti.

Exome‐wide association of deltamethrin resistance in Aedes aegypti from Mexico

“…In chromosome 3, the proportion of polymorphic sites among detox genes was 0.055 (3846/69 684), compared with 0.046 (109 310/2 360 622) (P = 1 × 10 −16 ). Furthermore, Campbell et al (2019) analysed a compilation of high-throughput sequencing data from three pyrethroid treatment groups and interrogated them to identify functional categories that were overrepresented among all coding genes. Of eight functional categories, three were overrepresented, as calculated by a hypergeometric test, which tests the probability of a gene being represented more often than expected by chance.…”

Effect of Selection for Pyrethroid Resistance on Abiotic Stress Tolerance in Aedes aegypti from Merida, Yucatan, Mexico

“…Other possible differences between strains include the management of reactive oxygen species produced during thermal stress [ 54 , 55 ], the homeoviscous adaptation potential of the cell membrane [ 56 , 57 ], or differential heat shock protein expression among the strains [ 58 , 59 , 60 , 61 ]. Heat Shock Protein STI1, for example, a protein that may act as a cochaperone mediating the activity of HSP70 and HSP90 [ 62 , 63 ], was found to genetically associate with insecticide resistance in A. aegypti [ 64 ]. Further studies will be necessary to help determine which physiological mechanisms set the upper thermal limits in mosquito larvae and how these are affected by selection for insecticide resistance.…”

Survei Entomologi, Kerentanan Aedes aegypti terhadap Insektisida Organofosfat, dan Identifikasi Gen VGSC di Dusun Malangrejo, Sleman, Yogyakarta

“…10 Perubahan genom pada nyamuk khususnya pada Voltage Gated Sodium Channel (VGSC) juga menjadi penyebab munculnya resistensi pada insektisida piretroid. 11 Penelitian yang melakukan survei entomologi dan status kerentanan terhadap beberapa jenis insektisida cukup banyak dilakukan, akan tetapi yang melihat aspek survei, kerentanan, dan deteksi gen di satu wilayah belum banyak dilakukan. Penelitian ini bertujuan untuk mengidentifikasi habitat perkembangbiakan Ae.…”

“…Kondisi resistensi ini dapat diturunkan dari generasi sebelumnya, 21 akan tetapi juga dapat disebabkan karena adanya mutasi pada gen VGSC yang berhubungan dengan aktivitas enzim. 10,11 Telah banyak penelitian yang menguji mekanisme penyebab terjadinya resistensi terhadap insektisida organofosfat. Penelitian di Kolombia menyatakan bahwa proses metabolik merupakan penyebab munculnya resistensi insektisida temefos.…”