Functional genomics for Chlamydia

项目总结/摘要 对于细菌病原体，开始确定微生物功能遗传性质的第一项研究是在 在全基因组范围内，通常代表着一个里程碑式的、具有高度影响力的成就。主要人体 病原体沙眼衣原体是一种细菌，在很大程度上还没有进行过此类研究 由于衣原体的专性细胞内性质和历史上的棘手性，以现代遗传扰动。 随着我们小组对衣原体的两种主要遗传工具-转座子诱变和 条件性温度敏感突变体-衣原体的功能基因组研究现在是可能的。 我们的长期目标是在全球范围内定义和功能性地描述遗传相关性， C.沙眼感染及发病机制。使用上述新方法，我们建议： (i)在模型中建立转座子和温度敏感条件突变体的定义突变体库 衣原体菌株，（ii）使用临床方法筛选这些库中的体外和体内生长缺陷标志 相关的鼠生殖道模型，和（iii）确定与宿主适应相关的衣原体基因 通过利用衣原体的种间横向基因转移和人类亲本菌株不能 感染老鼠 这些努力对于获得衣原体基因在衣原体感染中所起作用的功能性评价是必不可少的。 生物体的生长和发育，以及衣原体的进化适应，以成功地维持 复杂哺乳动物宿主的感染和发病机制。我们预计衣原体将作为一个模型， 专性细胞内细菌，因此，从这项工作中获得的知识将广泛扩展到 其他病原体在其哺乳动物宿主中同样进化出专性细胞内生态位。 这些位点的鉴定对于我们理解衣原体适应的机制是至关重要的， 哺乳动物宿主，是阐明主要毒力相关的重要一步， C.沙眼病毒

PROJECT SUMMARY/ABSTRACT For bacterial pathogens, the first studies that begin to define the microorganism’s functional genetic nature on a genome-wide scale, frequently represent a landmark and highly impactful achievement. The major human pathogen, Chlamydia trachomatis, is a bacterium for which such studies have not been performed, in large part due to Chlamydia’s obligate intracellular nature and historical intractability to modern genetic perturbations. With the development of two major genetic tools for Chlamydia by our group—transposon mutagenesis and conditional temperature-sensitive mutants—functional genomic investigations in Chlamydia are now possible. Our long term goal is to globally define and functionally characterize the genetic correlates to C. trachomatis infection and pathogenesis. Using the new approaches described above, we propose to: (i) build defined mutant libraries of transposon and temperature-sensitive conditional mutants in model Chlamydia strains, (ii) screen these libraries for hallmark in vitro and in vivo growth defects using a clinically relevant murine genital tract model, and (iii) determine the Chlamydia genes associated with host adaptation by exploiting interspecies lateral gene transfer for Chlamydia and the inability of human parental strains to infect mice. These efforts are essential for gaining a functional appreciation of the role chlamydial genes play in the organism’s growth and development, and also Chlamydia’s evolutionary adaptation to successfully maintain infection and pathogenesis in complex mammalian hosts. We anticipate that Chlamydia will serve as a model obligate intracellular bacterium, and, therefore, the knowledge obtained from this work will broadly extend to other pathogens that have similarly evolved an obligate intracellular niche in their mammalian hosts. Identification of these loci is critical for our understanding the mechanism of Chlamydia adaptation to mammalian hosts, and is an important step towards elucidating the major virulence correlates of C. trachomatis in humans.