Regulatory Role of Tandem Tryptophan Codons in Chlamydial Persistence

项目摘要：串联Trp密码子在衣原体持续存在中的调节作用 衣原体是一种专性细胞内细菌病原体，可导致一系列严重的疾病， 人类它是细菌性性传播感染（STI）的主要原因， 传染性可预防性失明、沙眼的病原体。衣原体感染的主要问题是， 他们往往是无症状和未确诊的，这可能导致慢性后遗症，如盆腔炎， 炎症性疾病和输卵管因素不孕症。因此，衣原体疾病仍然是一个重要的 给世界各地的医疗保健系统带来负担。为了适应专性细胞内生长， 衣原体已显着减少其基因组的大小和消除基因的各种途径，因为它 依赖宿主细胞来满足其代谢需求。大多数细菌对氨基酸限制的反应是 从事严格的反应，这是一个转录程序，用于适应营养不良， 条件严格的反应也直接与诱导持留细胞， 各种类型的细菌，它们的代谢活性有限，抗菌药物耐药性增强。 当营养素如色氨酸（trp）受到限制时，衣原体会变得持久。他们是 形态异常，显示失调的转录组，非复制，但仍保持活力。 衣原体缺乏必要的基因部署一个严格的反应，并有很少的确定 监管要素。它如何应对压力是一个有趣的问题。我们假设在trp期间 限制具有串联trp密码子的关键衣原体基因翻译的减少引发了 持续表型第一个项目目标是确定trp限制如何影响转录水平。 铁依赖性YtgR阻遏物的调节。我们将使用新一代RNA 测序，包括ChIP-seq和靶向转录测定来解决这个问题。第二 项目的目标是确定衣原体细胞分裂阻滞的机制， 集中于几个含有串联Trp密码子的细胞分裂基因。基因的组合 将使用方法和形态学研究来确定这一点。第三个项目目标是 通过细胞生物学研究监测宿主-病原体相互作用，包括营养获取。因为 与宿主-病原体相互作用相关的几个基因含有串联的Trp密码子， 内含物与宿主途径相互作用，细胞器预计会因色氨酸饥饿而改变; 参与包涵体完整性的途径得以维持，而那些支持衣原体完整性的途径 在整个发展周期中的进展受到负面影响。这项建议旨在 机械地连接色氨酸饥饿，通过串联色氨酸密码子基序调节翻译，和 与持久性有关的生理异常结果将导致新的鉴定 诊断和治疗目标，可以识别和治疗无症状衣原体感染。

Project Summary: Regulatory Role of Tandem Trp Codons in Chlamydial Persistence Chlamydia is an obligate intracellular bacterial pathogen that causes a range of serious diseases in humans. It is the primary cause of bacterial sexually transmitted infections (STI) and the causative agent of infectious preventable blindness, trachoma. The major concern of chlamydial infections is that they are often asymptomatic and undiagnosed, which can lead to chronic sequelae, such as pelvic inflammatory disease and tubal factor infertility. Consequently, chlamydial diseases remain a significant burden on health care systems around the world. In adapting to obligate intracellular growth, Chlamydia has significantly reduced its genome size and eliminated genes from various pathways as it relies on the host cell for its metabolic needs. Most bacteria respond to amino acid limitation by engaging a stringent response, which is a transcriptional program used to adapt to nutrient-poor conditions. The stringent response has also been directly connected with inducing persister cells in various types of bacteria, which have limited metabolic activity and increased antimicrobial resistance. Chlamydia can become persistent when limited for nutrients such as tryptophan (trp). They are morphologically aberrant, display a dysregulated transcriptome, non-replicating, yet remain viable. Chlamydia lacks the genes necessary to deploy a stringent response, and has very few identified regulatory elements. How it responds to stress is an intriguing question. We hypothesize that during trp limitation the decreased translation of key Chlamydia genes with tandem trp codons triggers a persistent phenotype. The first project goal is to determine how trp limitation impacts the transcriptional regulation by the iron-dependent YtgR repressor. We will use a combination of next-gen RNA sequencing, including ChIP-seq, and targeted transcriptional assays to address this. The second project goal is to determine the mechanism of chlamydial cell division blockage during persistence by focusing on several cell division genes containing tandem trp codons. A combination of genetic approaches and morphological studies will be used to determine this. The third project goal is to monitor host-pathogen interactions, including nutrient acquisition, via cell biological studies. Because several genes associated with host-pathogen interactions contain tandem trp codons, how the inclusion interacts with host pathways and organelles is predicted to be altered by trp starvation; pathways involved in inclusion integrity are maintained whereas those that support chlamydial progression through the developmental cycle are negatively impacted. The proposal aims to mechanistically link trp starvation, regulation of translation by tandem trp codon motifs, and physiological abnormalities linked to persistence. Results will lead to the identification of novel diagnostic and therapeutic targets that may identify and treat asymptomatic chlamydial infections.