title: Anopheles immune genes and amino acid sites evolving under the effect of positive selection.
abstract: BACKGROUND
  It has long been the goal of vector biology to generate genetic knowledge that can be used to "manipulate" natural populations of vectors to eliminate or lessen disease burden. While long in coming, progress towards reaching this goal has been made. Aiming to increase our understanding regarding the interactions between Plasmodium and the Anopheles immune genes, we investigated the patterns of genetic diversity of four anti-Plasmodium genes in the Anopheles gambiae complex of species.
  
  
  RESULTS
  Within a comparative phylogenetic and population genetics framework, the evolutionary history of four innate immunity genes within the An. gambiae complex (including the two most important human malaria vectors, An. gambiae and An. arabiensis) is reconstructed. The effect of natural selection in shaping the genes' diversity is examined. Introgression and retention of ancestral polymorphisms are relatively rare at all loci. Despite the potential confounding effects of these processes, we could identify sites that exhibited dN/dS ratios greater than 1.
  
  
  CONCLUSIONS
  In two of the studied genes, CLIPB14 and FBN8, several sites indicated evolution under positive selection, with CLIPB14 exhibiting the most consistent evidence. Considering only the sites that were consistently identified by all methods, two sites in CLIPB14 are adaptively driven. However, the analysis inferring the lineage -specific evolution of each gene was not in favor of any of the Anopheles lineages evolving under the constraints imposed by positive selection. Nevertheless, the loci and the specific amino acids that were identified as evolving under strong evolutionary pressure merit further investigation for their involvement in the Anopheles defense against microbes in general.
authors.affiliation: Department of Ecology and Taxonomy, Faculty of Biology, National and Kapodistrian University of Athens, Panepistimioupoli Zografou, Athens, Greece. aparmakel@biol.uoa.gr
authors.forename: Aristeidis
authors.initials: A
authors.lastname: Parmakelis
authors.forename: Marina
authors.initials: M
authors.lastname: Moustaka
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Poulakakis
authors.forename: Christos
authors.initials: C
authors.lastname: Louis
authors.forename: Michel A
authors.initials: MA
authors.lastname: Slotman
authors.forename: Jonathon C
authors.initials: JC
authors.lastname: Marshall
authors.forename: Parfait H
authors.initials: PH
authors.lastname: Awono-Ambene
authors.forename: Christophe
authors.initials: C
authors.lastname: Antonio-Nkondjio
authors.forename: Frederic
authors.initials: F
authors.lastname: Simard
authors.forename: Adalgisa
authors.initials: A
authors.lastname: Caccone
authors.forename: Jeffrey R
authors.initials: JR
authors.lastname: Powell
mesh_terms: D000596:Amino Acids / Q000235:genetics*; D000818:Animals; D000852:Anopheles / Q000235:genetics* / Q000276:immunology; D001483:Base Sequence; D017931:DNA Primers; D014644:Genetic Variation; D007109:Immunity / Q000235:genetics*; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D011995:Recombination, Genetic; D012641:Selection, Genetic
chemical_list: D000596:Amino Acids; D017931:DNA Primers