Project description:Culex pipiens pallens and Cx. p. quinquefasciatus are important vectors of many diseases, such as West Nile fever and lymphatic filariasis. The widespread use of insecticides to control these disease vectors and other insect pests has led to insecticide resistance becoming common in these species. High throughput screening using SSH and specific microarray platforms was thought to have identified some resistance-related genes. However, limitations of these methods meant that only a few hundred of the many thousand genes could be screened. It wasn’t until the sequencing of the Cx. quinquefasciatus genome in 2010 that it became possible to screen all 18.9 thousand genes in the mosquito genome for anti-insecticidal activity. We used high throughout Illumina sequencing to identify hundreds of Cx. p. pallens and Cx. p. quinquefasciatus genes that were differentially expressed in response to pesticide exposure. The identification of these genes is a vital first step for more detailed investigation of the molecular mechanisms involved in insecticide resistance in mosquitoes. In this study, larvae of Cx. pipiens pallens and Cx. pipiens quinquefasciatus were collected from field and transported to the laboratory and reared to adulthood to get F1 generation. Then, half of the F1 generation was conducted to pesticide bioassay. RNA extraction and Illumina sequencing were undertaken in another half of the F1 generation. Therefore, Samples used in Illumina sequencing did not contact any insecticides. Twelve Cx. pipiens pallens and Cx. pipiens quinquefasciatus lavae were undertaken Illumina RNA sequencing.
Project description:Culex pipiens pallens and Cx. p. quinquefasciatus are important vectors of many diseases, such as West Nile fever and lymphatic filariasis. The widespread use of insecticides to control these disease vectors and other insect pests has led to insecticide resistance becoming common in these species. High throughput screening using SSH and specific microarray platforms was thought to have identified some resistance-related genes. However, limitations of these methods meant that only a few hundred of the many thousand genes could be screened. It wasn’t until the sequencing of the Cx. quinquefasciatus genome in 2010 that it became possible to screen all 18.9 thousand genes in the mosquito genome for anti-insecticidal activity. We used high throughout Illumina sequencing to identify hundreds of Cx. p. pallens and Cx. p. quinquefasciatus genes that were differentially expressed in response to pesticide exposure. The identification of these genes is a vital first step for more detailed investigation of the molecular mechanisms involved in insecticide resistance in mosquitoes. In this study, larvae of Cx. pipiens pallens and Cx. pipiens quinquefasciatus were collected from field and transported to the laboratory and reared to adulthood to get F1 generation. Then, half of the F1 generation was conducted to pesticide bioassay. RNA extraction and Illumina sequencing were undertaken in another half of the F1 generation. Therefore, Samples used in Illumina sequencing did not contact any insecticides.
Project description:Culex pipiens molestus and Cx. p. quinquefasciatus are the members of Culex pipiens Complex, but they display relatively large differences in behavior and physiological responses. We compared the genes of these mosquitoes to identify those that were differentially expressed in each subspecies. Such genes could play important roles in subspecies-specific blood feeding or oviposition behavior.
Project description:Culex pipiens molestus and Cx. p. quinquefasciatus are the members of Culex pipiens Complex, but they display relatively large differences in behavior and physiological responses. We compared the genes of these mosquitoes to identify those that were differentially expressed in each subspecies. Such genes could play important roles in subspecies-specific blood feeding or oviposition behavior. Culex pipiens molestus and Cx. p. quinquefasciatus females were undertaken Illumina RNA sequencing.
Project description:Investigation of gene expression level differences in Culex pipiens (SB) and C. quinquefasciatus (JHB) at three time points (8, 16, and 24 hours post-exposure) during the early pupal state in standard (25°C; 16 h light/8 h dark) and diapause-inducing (18°C; 8 h light/16 h dark) conditions. A forty-eight chip study (4 Expr12x135K slides) using cDNA from total RNA collected from two species in the Culex pipiens complex at 3 time-points during the early pupal stage to study gene expression differences between standard (25°C; 16 h light/8 h dark) and diapause-inducing (18°C; 8 h light/16 h dark) conditions, and between Culex pipiens (diapause) and C. quinquefasciatus (no diapause). Each chip measures the expression level of 18,692 protein coding genes, with 3 probes per gene and two-fold technical redundancy. Each of the 12-plex slides was used for one of four biological replicates. Probes were designed using the C.quinquefasciatus CpipJ1.2 geneset in VectorBase.
Project description:A pyrethroid-resistant strain of Culex quinquefasciatus, JPal-per, exhibits 2500-fold greater larval resistance to permethrin than the insecticide-susceptible strain Ogasawara. An increased microsome monooxygenase metabolism is involved in the resistance mechanism. Microarray analysis revealed altered expressions of cytochrome P450 genes in the fourth instar larvae of JPal-per compared to those in OGS. An oligo DNA array was designed for 62 different cDNA segments encoding unique P450 isoforms of the Cx. pipiens complex. Other probes for non-P450 Cx. pipiens complex genes were also mounted on the array.