Regulatory Role of Tandem Tryptophan Codons in Chlamydial Persistence

项目摘要：串联色氨酸密码子在衣原体持久性中的调节作用 衣原体是一种专性的细胞内细菌病原体，在 人类。它是细菌性传播感染(STI)的主要原因，也是 传染性可预防失明的病原体沙眼。衣原体感染的主要问题是 它们通常是无症状和未确诊的，这可能会导致慢性后遗症，如骨盆 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。在适应专属细胞内生长的过程中， 衣原体显著缩小了其基因组大小，并消除了各种途径的基因，因为它 依赖宿主细胞满足其新陈代谢需求。大多数细菌对氨基酸限制的反应是 进行严格的反应，这是一种用于适应营养贫乏的转录程序 条件。这种严格的反应也直接与诱导永生化细胞有关。 各种类型的细菌，代谢活性有限，抗菌力增强。 当限制色氨酸(Trp)等营养物质时，衣原体可能会持续存在。他们是 形态异常，表现为不受调控的转录组，不可复制，但仍可存活。 衣原体缺乏部署严格反应所需的基因，而且很少被发现。 监管要素。它如何应对压力是一个耐人寻味的问题。我们假设在TRP期间 限制衣原体关键基因与串联Trp密码子的翻译减少触发 持久的表型。第一个项目目标是确定Trp限制如何影响转录 受铁依赖的YtgR抑制因子的调节。我们将使用下一代RNA的组合 测序，包括芯片序列和有针对性的转录分析，以解决这一问题。第二 项目目标是确定持续期间衣原体细胞分裂受阻的机制 聚焦于含有串联Trp密码子的几个细胞分裂基因。一种基因的组合 将使用方法和形态研究来确定这一点。第三个项目目标是 通过细胞生物学研究监测宿主-病原体的相互作用，包括营养获取。因为 几个与宿主-病原体相互作用相关的基因包含串联的Trp密码子，如何 包涵体与宿主途径和细胞器相互作用，预计会因色氨酸饥饿而改变； 参与包涵体完整性的途径得到维护，而那些支持衣原体的途径 在整个发育周期中的进展受到负面影响。该提案旨在 从机制上讲，Trp饥饿、串联Trp密码子基序对翻译的调节以及 与持久性有关的生理异常。结果将导致对小说的鉴定 可识别和治疗无症状衣原体感染的诊断和治疗靶点。

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.