Project description:We sequenced and assembled de novo the coding transcriptomes in four species of Notothenioid fish: Neopagetopsis ionah (Jonah’s ice fish), Pseudochaenichtys georgianus (South Georgia icefish), Harpagifer antarcticus (Antarctic spiny plunderfish) and Parachaenichthys charcoti (Charcot’s dragonfish). We sampled 1-4 individuals and 1-14 tissues (brain, white muscle, liver, head kidney, trunk kidney, skin, heart, red muscle, spleen, ovary, testis, whole blood, gill, red blood cells) in each species, depending on tissue availability.
Project description:Evolving resistance to artemisinin-based compounds in SE Asia threatens to derail attempts to control and eliminate malaria. Resistance has been confirmed in western Cambodia, has recently emerged in western Thailand, but is absent from neighboring Laos. Artemisinin resistance results in reduced parasite clearance rates (CR) from the blood following treatment. We used a two-phase approach to identify the genes underlying this ongoing selective event. Comparison of geographical differentiation and haplotype structure at 6,969 polymorphic SNPs in 91 parasites from western Cambodia, western Thailand and Laos identified 33 strongly selected genome regions. We screened SNPs and microsatellites within these genome regions in 718 parasites from western Thailand, and identified a 35kb region of chr 13 showing strong association (P=10-6 to 10-11) with slow CR. This region contains several compelling candidate loci, such as HSP70, for assessment by transfection. These results illustrate the efficacy of targeted association for identifying the genetic basis of adaptive traits.