Kelch structure, the position of mutations in the pfKelch13 gene, and a theoretical functional model. (a) Homology model of PfKelch13p (amino acids 444 through 723) generated using SWISS-MODEL and the human Kelch-like protein 12 crystral structure (2vpj.1.A) as a template. Two rotation views are shown. (b) Predicted domains and locations of mutations in pfkelch13 (PF3D7_1343700) identified either in vitro , or in vivo ,. Mutations in pink are in the Kelch domain modeled above while green ones are in the predicted regions with more ambiguous function. Mutations mentioned in the text are specifically indicated. In addition to Kelch domains, PfKelch13p contains a BTB domain, typically involved in dimerization. (c) Theoretical model of PfKelch function in artemisinin resistance. See Box 3 for details. TF, transcription factor.