Mutualism Breakdown by Amplification of Wolbachia Genes

摘要: Most insect species are associated with vertically transmitted endosymbionts. Because of the mode transmission, fitness these symbionts is dependent on hosts. Therefore, endosymbionts need to control their proliferation in order minimize cost for host. The genetic bases and mechanisms this regulation remain largely undetermined. maternally inherited bacteria genus Wolbachia most common insects, providing some them benefits. In Drosophila melanogaster, wMelPop a unique virulent variant that proliferates massively hosts shortens lifespan. virulence unknown, identification would allow better understanding how levels regulated. Here we show amplification region containing eight genes, called Octomom, responsible virulence. Using lines selected carrying different Octomom copy numbers, demonstrate number copies determines titers strength lethal phenotype. unstable, reversion one reverts all phenotypes. Our results provide link between genotype phenotype identify genomic regulating proliferation. We also prove can evolve rapidly. Rapid evolution by changes gene may be high mobile elements other repeated regions. Understanding pathogenicity variability allows researchers predict outcome releasing mosquitoes transinfected block human vector-borne diseases. transition from mutualist pathogen occur because single change endosymbiont. This implies there must constant selection densities.