Regulation of HTLV-I replication by the viral p30

病毒 p30 对 HTLV-I 复制的调节

• 批准号: 6984616
• 负责人: CHRISTOPHE P NICOT
• 金额: $ 21.87万
• 依托单位: UNIVERSITY OF KANSAS MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-07-08 至 2010-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6984616
• 关键词: RNA binding protein; Saimiri; clinical research; gel mobility shift assay; genetic transcription; green fluorescent proteins; human T cell lymphotropic virus type 1; human tissue; immunofluorescence technique; intermolecular interaction; laboratory rabbit; latent virus infection; longitudinal animal study; longitudinal human study; molecular /cellular imaging; molecular cloning; polymerase chain reaction; posttranscriptional RNA processing; protein structure function; provirus; virus RNA; virus protein; virus replication; western blottings

DESCRIPTION (provided by applicant): The human T-cell lymphotropic virus type 1 (HTLV-I) is epidemiologically associated with an aggressive and fatal T-cell type leukemia/ lymphoma designated Adult T-cell Leukemia/ Lymphoma (ATLL). HTLV-I infection is also associated with a progressive myelopathy designated Tropical Spastic Paraparesis/ HTLV-I Associated Myelopathy (TSP/HAM). It is estimated that 20 to 30 million people worldwide are infected with HTLV-I. HTLV-I possesses unusual features that would not predict its survival in an immune-competent host: The virus is poorly infectious but elicits a vigorous humoral and cellular host immune response. In addition, HTLV-I is mainly replicated in vivo through division of infected cells and therefore presents a very low antigenic variability. However, in spite of these apparent disadvantages the virus has persisted in humans for more than 100,000 years, indicating that HTLV-I has efficiently adapted to its host. We have recently found that HTLV-I has evolved a protein, p30, that interacts specifically with the tax/rex viral RNA encoding positive regulators of virus expression. Because p30 is unable to shuttle out of the nucleus, tax/rex RNA is trapped in the nucleus and expression of these proteins is inhibited. The goals of this study are to uncover the molecular mechanisms involved in p30-viral RNA interactions and p30 effects on transcription leading to inhibition of virus replication and latency. Four specific aims are proposed. Aim 1) Investigate biochemical characteristics of p30-RNA interactions. Define the minimal p30-response RNA sequence within HTLV-I provirus and identify the domain(s) of the p30 protein involved in these interactions. Aim 2) Analyze transcriptional and post transcriptional effects of p30 on HTLV-I replication in vivo and in vitro. Specific mutants unable to interact with transcriptional regulator CBP/p300 or with viral RNA will be generated in order to discriminate each activity of p30. Aim 3) Investigate molecular determinants for the nuclear/nucleolar retention of p30 and the effects of p30 on Rex-RNA binding activity or Rex functions and vice versa. Aim 4) Study the kinetics of p30 and tax/rex RNA expression in relation to virus expression in vitro using molecular clones mutated for p30. Kinetics of viral RNA expression will be studied in vivo in different lymphoid tissues collected longitudinally from an infected squirrel monkey model and in asymptomatic or HTLV-I-infected patients with neurological or hematological disorders.

描述（由申请人提供）：人类T细胞淋巴细胞病毒1型（HTLV-I）在流行病学上与侵略性且致命的T细胞型白血病/淋巴瘤指定成人T细胞白血病/淋巴瘤（ATLL）相关。 HTLV-1感染也与进行性骨髓病的指定热带痉挛性瘫痪/ HTLV-1相关的骨髓病（TSP/ HAM）有关。 据估计，全世界有20至3000万人感染了HTLV-I。 HTLV-I具有不寻常的特征，这些特征无法预测其在免疫能力的宿主中的生存：该病毒感染力不佳，但引起了剧烈的体液和细胞宿主免疫反应。 此外，HTLV-I主要通过感染细胞分裂在体内复制，因此提出非常低的抗原变异性。 然而，尽管存在这些明显的缺点，该病毒已经在人类中持续了100，000多年，这表明HTLV-I有效地适应了其宿主。 我们最近发现，HTLV-I已进化了一种蛋白质P30，该蛋白与编码病毒表达阳性调节剂的税/REX病毒RNA相互作用。 由于P30无法从核中脱离核，因此税/REX RNA被困在细胞核中，并且这些蛋白质的表达受到抑制。 这项研究的目标是发现参与P30-病毒RNA相互作用的分子机制以及P30对转录的影响，从而抑制病毒复制和潜伏期。 提出了四个具体目标。目标1）研究P30-RNA相互作用的生化特征。 定义HTLV-I Profirus内的最小P30响应RNA序列，并确定与这些相互作用有关的P30蛋白的结构域。 目标2）分析P30对体内和体外HTLV-I复制的转录和转录后作用。 将生成无法与转录调节剂CBP/P300相互作用或与病毒RNA相互作用的特定突变体，以区分P30的每种活性。 目标3）研究P30的核/核仁保留率的分子决定因素以及P30对REX-RNA结合活性或REX功能的影响，反之亦然。 AIM 4）研究P30和税收/REX RNA的动力学，使用对P30突变的分子克隆在体外与病毒表达有关。 病毒RNA表达的动力学将在从感染的松鼠猴子模型以及无症状或HTLV-I感染的患有神经或血液学疾病的患者中纵向收集的不同淋巴组织中研究。