title: Genetic correlation between melanization and antibacterial immune responses in a natural population of the malaria vector Anopheles gambiae.
abstract: The immune system of invertebrates can mount different responses, including melanotic encapsulation and several antibacterial defense mechanisms. Variation of the efficacies of these responses is generally considered to be a product of the evolutionary pressure on each response due to infection by parasites. However, potential interactions and trade-offs among the different responses of the immune system could constrain the evolutionary potential of each response. In a natural population of the mosquito Anopheles gambiae, we measured the genetic association between the melanization response and an antibacterial response in two environmental qualities (well-fed and undernourished larvae). In both environments the two immune responses were positively genetically correlated: in full-sib families that were most likely to melanize a bead, injected bacteria were most likely to be cleared. Thus, our data do not support the idea of a trade-off among different outcomes of the invertebrate immune system, but rather that some families are overall immunologically superior to others.
authors.affiliation: Laboratoire de Parasitologie Evolutive, CNRS UMR 7103, Université Pierre and Marie Curie, CC237, 7 quai St Bernard, 75252 Paris Cedex 05, France. Louis.Lambrechts@snv.jussieu.fr
authors.forename: Louis
authors.initials: L
authors.lastname: Lambrechts
authors.forename: John M
authors.initials: JM
authors.lastname: Vulule
authors.forename: Jacob C
authors.initials: JC
authors.lastname: Koella
mesh_terms: D000704:Analysis of Variance; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D000852:Anopheles / Q000235:genetics / Q000276:immunology* / Q000382:microbiology; D001837:Body Weights and Measures; D004926:Escherichia coli / Q000276:immunology; D005260:Female; D007113:Immunity, Innate / Q000235:genetics / Q000276:immunology*; D007630:Kenya; D008543:Melanins / Q000276:immunology; D008863:Microspheres; D010858:Pigmentation / Q000235:genetics / Q000276:immunology*; D019655:Quantitative Trait, Heritable
chemical_list: D008543:Melanins