Coevolutionary dynamics of Wolbachia multiply infesting the azuki bean beetle

为了阐明侵染赤豆天牛的沃尔巴克氏体（Wolbachia）的3个不同菌株（Con、Ori、Aus）的进化和生态状况，我们通过实验研究了沃尔巴克氏体菌株之间的体内相互作用，并利用计算机模拟研究了宿主种群中沃尔巴克氏体的流行条件。(1)Wolbachia感染对宿主的适应度成本我们量化了Wolbachia感染对宿主适应度的成本。健身的主机双重感染Con和Ori显着低于主机单独感染Con或Ori。结果定量地显示了“多重感染”的病灶。(2)Wolbachia向寄主的水平基因转移通过与有Aus和无Aus寄主的杂交试验，发现Aus菌株在F1和F2代均遵循X连锁基因的分离模式。赤小豆甲虫具有XY性染色体，这一结果表明Aus不是胞内细菌， ...更多信息 该基因组片段转移到了宿主的X染色体上，表明基因是从原核生物水平转移到真核生物宿主昆虫中的。(3)Wolbachia菌株之间的体内相互作用我们使用定量PCR定量了Ori和Con之间的相互作用。在与Ori共同感染的宿主中，Con的细胞密度显著低于单独感染Con的宿主。Ori对Con的抑制作用大于Ori对细胞密度的抑制作用，表明两菌株间存在拮抗作用或化感作用。(4)通过宿主上的沃尔巴克氏体定量细胞质不相容性在沃尔巴克氏体的每个菌株中定量细胞质不相容性的强度。Con表现为完全不亲和性（胚期死亡率为100%），Ori表现为中度不亲和性（胚期死亡率为40%），Aus不表现不亲和性。(5)基于上述结果，我们正在构建基于个体的模型，该模型将集合种群结构和局部种群动态的冲刷-崩溃循环结合起来。我们正在分析共同进化动力学中多重共同感染的条件。少

To elucidate the evolutionary and ecological status of three different strains (Con, Ori, Aus) of Wolbachia infesting the azuki bean beetle, Callosobruchus chinensis, we studied intra-body interactions among Wolbachia strains experimentally and examined prevailing conditions of Wolbachia in the host population, using computer simulation.(1) Fitness cost of Wolbachia infection on the hostWe quantified the cost of Wolbachia infection on the host fitness. Fitness of the host doubly infected with both Con and Ori was significantly lower than the host singly infected with either Con or Ori. The result shows ilemma of multiple infection" quantitatively.(2) Horizontal gene transfer from Wolbachia to the host insectCross-experiment between the hosts which has either Aus or not showed that the strain Aus followed the segregation pattern of the X-linked gene in F1 and F2 generations. The azuki bean beetle has XY sexual chromosome, and this result showed that Aus is not the bacteria of intracellu … More lar endo-symbiont but the genome fragment transferred on the host X chromosome, which suggests the horizontal gene transfer from the prokaryote to the eukaryote, the host insect.(3) Intra-body interaction between Wolbachia strainsWe quantified interactions between Ori and Con, using quantitative PCR. Cell density of Con was significantly lower in the doubly infected host together with Ori than that in the singly infected host with Con only. Con was suppressed disproportionately by Ori, more than the latter's the cell density, which suggests antagonistic interaction or allelopathy between the two strains.(4) Quantification of cytoplasmic incompatibility by Wolbachia on the hostStrength of cytoplasmic incompatibility was quantified in each strain of Wolbachia. Con showed the complete incompatibility (100% death in the embryo stage), Ori did middle (40% death) and Aus did not have any incompatibility.(5) Simulation analysis using an individual-based model, incorporating metapopulation structureBased on the aforementioned results, we are constructing the individual-based model that incorporates metapopulation structure and flush-crash cycle of local population dynamics. We are analyzing the conditions for multiple co-infection in co-evolutionary dynamics. Less