The role of CITFA-2 in RNA polymerase I transcription in Trypanosoma brucei

CITFA-2 在布氏锥虫 RNA 聚合酶 I 转录中的作用

• 批准号: 9122304
• 负责人: Justin Kirkham
• 金额: $ 2.8万
• 依托单位: UNIVERSITY OF CONNECTICUT SCH OF MED/DNT
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-09-16 至 2017-05-08
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9122304
• 关键词: Affinity; Africa South of the Sahara; African Trypanosomiasis; Agriculture; Antigenic Variation; Area; Binding; Blood Circulation; Cell Cycle Arrest; Cell Nucleolus; Cell Survival; Cessation of life; Complex; DNA; DNA Binding; Data; Detection; Disease; Drug resistance; Economics; Electrophoretic Mobility Shift Assay; Elements; Epidemic; Eukaryota; Gene Family; Genes; Genetic Transcription; Glycoproteins; Goals; Human; Immune; Immune response; Immune system; In Vitro; Infection; Intervention; Laboratories; Left; Life; Livestock; Lymphatic System; Mediating; Membrane Glycoproteins; Modeling; Mus; Mutation; Parasites; Pharmaceutical Preparations; Play; Population; Proteins; Proteomics; RNA Interference; RNA Polymerase I; Rattus; Recombinant DNA; Recombinants; Resistance; Risk; Role; Site; Staging; System; Techniques; Testing; Transgenes; Trypanosoma; Trypanosoma brucei brucei; Tsetse Flies; Vaccines; Variant; Work; base; burden of illness; combat; disorder control; dynein light chain; extracellular; factor A; fascinate; in vivo; interest; member; nagana; new therapeutic target; promoter; public health relevance; tool; transcription factor; vector

DESCRIPTION (provided by applicant): Trypanosoma brucei is transmitted by the Tsetse fly in sub-Saharan Africa and is the causative agent of Human African Trypanosomiasis, also known as Sleeping Sickness, which is responsible for a considerable disease burden and loss of life. T. brucei also causes Nagana, a corresponding disease in livestock, which creates a barrier to agricultural and economic progress in the areas it is endemic. Control of this disease is tenuous, at best, due to a lack of safe, effective, and easily administered treatment options. Additionally, due to increasing drug resistance, there is concern that re-emergence of the disease may occur, as has happened in the past. It is therefore imperative that additional understanding of this parasite be gained. T. brucei has evolved numerous immune evasion techniques that make it well suited to its various mammalian hosts, most notable of which is its ability of antigenic variation. In the mammalian bloodstream, T. brucei is completely covered by a dense coat of variant surface glycoprotein (VSG) that is expressed from a single gene drawn from a large gene family. Antigenic variation is achieved by periodically switching to the expression of a different VSG gene, which results in a new parasite population which escapes detection by the immune system. Moreover, VSG expression is essential for parasite viability even in the absence of immunological forces (i.e. in culture). The main goal of this project is to study the specific function of the essential subunit 2 of class I transcription factor A (CITFA) tht is absolutely required for VSG transcription. Preliminary data indicates that CITFA-2 directly contacts the promoter and is less abundant than other CITFA subunits, suggesting that it plays a key role in regulating monoallelic VSG expression. Additionally, CITFA-2 inclusion appears to define the active CITFA complex. CITFA-2 can therefore be used as a tool for isolation and identification of proteins which associate specifically with active CITFA.

描述（由申请人提供）：布氏锥虫由撒哈拉以南非洲的采采蝇传播，是非洲人类锥虫病（也称为昏睡病）的病原体，造成相当大的疾病负担和生命损失。T.布氏杆菌还引起Nagana病，这是牲畜中的一种相应疾病，它对流行地区的农业和经济进步造成障碍。这种疾病的控制是脆弱的，充其量，由于缺乏安全，有效，易于管理的治疗方案。此外，由于耐药性增加，人们担心可能会像过去那样再次出现这种疾病。因此，必须对这种寄生虫有更多的了解。T.布氏杆菌已经进化出许多免疫逃避技术，使其非常适合于其各种哺乳动物宿主，其中最值得注意的是其抗原变异的能力。在哺乳动物的血液中，T.布氏杆菌完全被从来自大基因家族的单个基因表达的变异表面糖蛋白（VSG）的致密外壳覆盖。通过周期性地切换到不同VSG基因的表达来实现抗原变异，这导致新的寄生虫种群逃避免疫系统的检测。此外，VSG表达对于寄生虫生存力是必需的，即使在没有免疫力的情况下（即在培养物中）。本项目的主要目的是研究VSG转录所必需的I类转录因子A（CITFA）的必需亚基2的特异性功能。初步数据表明，CITFA-2直接接触的启动子，比其他CITFA亚基的丰度低，这表明它在调节单等位基因VSG表达的关键作用。此外，CITFA-2包含物似乎定义了活性CITFA复合物。因此，CITFA-2可用作分离和鉴定与活性CITFA特异性相关的蛋白质的工具。