Experimental evolution of specialization by a microsporidian parasite

BMC Evolutionary Biology

Research Article

Jacob C Koella¹  Mathieu Legros² 

[1] Laboratoire de Parasitologie Evolutive, CNRS UMR 7103, Université Pierre et Marie Curie Paris VI, 7 quai Saint Bernard, 75005, Paris, France;Division of Biology, Imperial College London, Silwood Park Campus, SL5 7PY, Ascot, UK;Laboratoire de Parasitologie Evolutive, CNRS UMR 7103, Université Pierre et Marie Curie Paris VI, 7 quai Saint Bernard, 75005, Paris, France;Entomology Dpt, North Carolina State University, 840 Method Rd. Unit 1, 27607, Raleigh, NC, USA;

关键词: Host Population;    Isofemale Line;    Specialized Parasite;    Antagonistic Pleiotropy;    Evolution Regime;   

DOI  :  10.1186/1471-2148-10-159

 received in 2010-02-19, accepted in 2010-05-28,  发布年份 2010

来源: Springer

【 摘 要 】

BackgroundEvolutionary theory predicts that the pressure for parasites to specialize on one host or to become generalists on a wide range of hosts is driven by the diversity or temporal variability of the host's population and by genetic trade-offs in the adaptation to different hosts. We give experimental evidence for this idea by letting the parasite Brachiola algerae evolve on one of four genetically homogeneous lines of the mosquito Aedes aegypti, on a mixture of the four lines or on an alternating sequence of the four lines. The first regime was expected to lead to specialists, the other two to generalists. After 13 generations, we tested the evolved parasites on each of the four lines of the mosquito.ResultsThe specialized parasites were most infective on their own isofemale line and least infective on other isofemale lines, while the generalist parasites had intermediate infection success on all lines. The success of a specialist on its matched mosquito line was negatively correlated with its success on other lines, suggesting an evolutionary cost to specialization. This trade-off was corroborated by the observation that the generalists had higher average mean infectivity than the specialists over all isofemale lines.ConclusionsOverall, our experiment reveals the potential for specialization of a parasite to individual genotypes of its host and provides experimental evidence of the cost associated with the evolution of specialization, an important feature for understanding the coevolutionary dynamics between hosts and parasites.

【 授权许可】

CC BY   
© Legros and Koella; licensee BioMed Central Ltd. 2010