Regulatory mechanisms involved in the control of <i>CYP6M2</i> gene in insecticide resistant <i>Anopheles gambiae</i> (Diptera: culicidae)

Cytochrome P450s, including <i>CYP6M2</i> gene, are involved in the detoxification of permethrin. Some of these genes are regulated by <i>CnCC / dKeap</i> 1 and Spineless / <i>Tango </i>in <i>Drosophila melanogaster</i>. This mechanism is yet to be identified in <i>Anopheles gambiae</i>. Thus, we examine whether there is differential regulation of <i>CYP6M2</i> gene between permethrin resistant Tiassalé and susceptible Kisumu strains of <i>An. gambiae</i>. Bioinformatics analysis was used to search for cis-acting elements within <i>CYP6M2</i> (896 bp) region hypothesised to contain the promoter. Isolated and cloned <i>CYP6M2 </i>promoter reporter constructs were transfected into <i>Anopheles gambiae</i> Sua 5.1* cells to measure luciferase activity as a surrogate promoter activity. The WHO adult bioassay was used to expose adult females of the permethrin resistant Tiassalé and susceptible Kisumu strains of <i>An. gambiae</i> to discriminating doses of 0.75% permethrin. Uncharacterised strains from Auyo (Auyo-Nigeria) selected to 4% DDT and 0.1% Bendiocarb as recommended by WHO were also studied. Total RNA was isolated from the respective selected and unselected strains of <i>An. gambiae</i> and cDNA synthesised. Semi and Real time quantitative PCR (qPCR) using SYBR® Green were used to determine the gene expression and regulation levels. Results established the presence of putative AGAP010259 (A<i>h</i>R) and AGAP005300 (Nf2e1) <i>cis</i>-acting elements within <i>Anopheles gambiae CYP6M2</i> promoters <i>in silico</i>. Luciferase reporter gene assays revealed no promoter activity as confirmed by using <i>CYP9M10</i> promoter from <i>Culex quinquefasciatus</i> with a known promoter activity as control. There is higher expression of Nf2e1 than AGAP010259 and a variable expression of <i>CYP6M2</i> in all the insecticide selected individuals, which may potentially be associated with insecticide resistance. This study provides useful information on our understanding of the regulatory mechanisms involved in insecticide resistance. These results have implications for the control of mosquito populations and the global spread of human, livestock and poultry diseases.<br/>

Name dc:type.qualificationname

PhD

Level dc:type.qualificationlevel

Doctoral Thesis

Grantor dc:publisher.institution

Abertay University

Year dc:date.issued

2014

Author dc:creator

• Mohammed Rabiu, Balarabe

Advisors dc:contributor.advisor

• Deeni, Yusuf
• Collier, Phillip

Language dc:language

eng

Identifier

oai:rke.abertay.ac.uk:studenttheses/75a1f78b-2d00-49d7-a564-d67ef369eb83

OAI identifier oai:identifier

oai:rke.abertay.ac.uk:studenttheses/75a1f78b-2d00-49d7-a564-d67ef369eb83