DISSERTATION RESEARCH: Evolutionary History of Symbiotic Bacteria in Bird Lice

在羽虱属中，至少有两组内共生细菌。尽管这些细菌是通过母体传播的，必须在虱子内部才能存活，但它们的进化树并不反映它们生活在其中的虱子的进化树。这种不一致可能是因为在一些科伦比克拉物种中，一组共生体被另一组所取代。将产生两种虱子的共生体的基因组序列，柱状隐杆线虫和杆状线虫。这些数据将用于比较这两种共生体的基因清单、基因组组织和基因组大小。如果原始共生体已经在一些科伦比克拉物种中被取代，那么我们预计每个共生体群体的这些基因组特征将非常不同。这项研究产生的基因组序列将是以角蛋白(羽毛或毛发)为食的昆虫共生体的第一个。这项研究将提高我们对共生关系的认识，特别是细菌共生体的可能替代和随后的进化。此外，这项工作将为一名女博士生和几名本科生提供生物信息学和基因组学领域的培训。使用世界性的岩鸽作为丛林共生系统的模型，K-12的学生将被教育关于共生以及遗传和进化的重要性。这项工作产生的所有序列数据将提交给NCBI Genbank公共数据库。

Within the feather louse genus Columbicola there are at least two groups of endosymbiotic bacteria. Although these bacteria are transmitted maternally and must be inside of a louse to remain alive, their evolutionary tree does not mirror that of the lice they live in. This incongruity might be explained by the replacement of one group of symbionts with another group in some of the species of Columbicola. Genome sequences will be produced for the symbionts of two lice species, C. columbae and C. baculoides. These data will be used to compare the gene inventory, genome organization and genome size of the two symbionts. If the ancestral symbiont has been replaced in some species of Columbicola, then we expect that these genomic characteristics will be very different for each of the symbiont groups. The genome sequences produced from this study will be the first for symbionts of insects that feed on keratin (feathers or hair). This study will improve our knowledge of symbiotic relationships, in particular the possible replacement and subsequent evolution of bacterial symbionts. In addition, this work will provide training in the fields of bioinformatics and genomics for a female PhD student and several undergraduates. Using the cosmopolitan Rock Pigeon as a model for the Columbicola-symbiont system, K-12 students will be educated about symbiosis and the importance of genetics and evolution. All sequence data produced from this work will be submitted to the NCBI Genbank public database.