Effect of coinheritance on host-pathogen coevolution

描述（由申请人提供）：拟议研究的总体目标是开发必要的遗传理论，以了解宿主和微生物基因组的共传播模式如何影响共生和致病细菌与其宿主的共同进化。我们的方法是新颖的，因为它扩展了为模拟单个基因组内的核基因组合的遗传而开发的理论，以跨越两个基因组的基因组合，即宿主和病原体的基因组合。当应用于核和线粒体基因组合时，这种方法成功地预测了功能基因从线粒体转移到核的频率：功能基因的基因组间转移在近亲繁殖物种中发生的可能性是在异交物种中的10倍。交配系统对基因转移产生这种影响的原因是，线粒体和核基因一起遗传的交配系统比基因独立遗传的交配系统更能有效地对基因组合起作用。虽然线粒体是完全垂直传输像一些内共生体，类似的效果预计将表现在系统中只有部分垂直传输，我们将发展这个更普遍的理论。双位点遗传理论量化了相同或不同基因组中基因组合的共同遗传，决定了每个物种中基因进化轨迹的结合程度。这决定了宿主-病原体联合体是朝着增强的毒力发展还是朝着良性共生发展。 项目叙述：传播速率的变化从根本上改变了宿主及其病原体的遗传共同进化，并有助于新疾病的出现。虽然在单个宿主世代内受感染宿主的传播和疾病流行病学之间的直接联系是众所周知的，但对疾病从一代宿主传播到下一代宿主的遗传后果知之甚少。该提案将发展遗传理论，以解决宿主基因和宿主病原体的共同遗传如何影响疾病毒力的进化。

DESCRIPTION (provided by applicant): The overall goal of the proposed research is to develop the genetic theory necessary for understanding how patterns of co-transmission of host and microbial genomes affect the co-evolution of symbiotic and pathogenic bacteria with their hosts. Our approach is novel in that it extends theory developed for modeling the inheritance of nuclear gene combinations within single genomes to gene combinations across two genomes, those of host and pathogen. When applied to nuclear and mitochondrial gene combinations, this approach successfully predicted the frequency of functional gene transfer from the mitochondria to the nucleus: inter-genomic transfer of functional genes is ten-fold more likely to occur in inbreeding species than in outcrossing species. The reason for this effect of mating system on gene transfer is that mating systems, where mitochondrial and nuclear genes are inherited together, allow natural selection to act more effectively on gene combinations than mating systems where the genes are inherited independently. Although mitochondria are wholly vertically transmitted like some endosymbionts, similar effects are expected to be manifest in systems with only partial vertical transmission and we will develop this more general theory. Two-locus descent theory quantifies the coinheritance of gene combinations in the same or different genomes, determining the degree to which the evolutionary trajectories of genes in each species are conjoined. This determines whether a host-pathogen association will develop toward enhanced virulence or toward benign symbiosis. Project Narrative: Change in the dispersal rates fundamentally change the genetic coevolution both hosts and their pathogens and contribute to the emergence of new diseases. Although a direct link between dispersal of infected hosts and disease epidemiology within a single host generation is well known, the genetic consequences of disease transmission from one generation of hosts to the next is much more poorly understood. This proposal will develop genetic theory for addressing how the co-inheritance of host genes and host pathogens affects the evolution of disease virulence.