Adenovirus manipulation of cellular chromatin to overcome host responses

项目摘要 逃避抗病毒免疫应答的需要已经推动了病毒策略的进化，以操纵宿主细胞， 染色质，控制基因表达和破坏细胞防御。腺病毒是普遍存在的病毒， 为理解基本细胞过程提供了重要的模型系统， 用于治疗目的的载体。腺病毒及其衍生载体的感染可引起强烈的先天性免疫 反应，影响疾病的过程和它们作为基因传递载体的有效性， 预防针因此，了解破坏宿主反应的病毒蛋白对于治疗 感染和改善治疗载体应用。在这里，我们重点关注腺病毒蛋白VII，主要 核心蛋白，以前被认为专门用于包装病毒基因组。我们发现 在腺病毒感染期间，蛋白VII在病毒和宿主基因组中都具有意想不到的作用。很长的- 该项目的长期目标是破译这种组蛋白样病毒蛋白如何克服先天宿主反应， 促进感染性病毒后代的产生。我们最近发现，蛋白质VII结合DNA， 核小体，具有类似于组蛋白的转录后修饰（PTM），并在细胞核中积累。 染色质在感染过程中。我们证明了蛋白VII可以改变宿主蛋白质的组成 与感染细胞核中的病毒基因组相关，并且还在细胞内隔离宿主因子。 染色质我们的中心假设是腺病毒蛋白VII模拟组蛋白，作为一种潜在的 操纵病毒和细胞染色质以破坏先天宿主反应的策略。这本小说 在我们实验室使用新工具产生的大量初步数据的基础上， 我们已经产生了研究蛋白质VII是如何必要和足够的对抗细胞免疫反应。 这两个整合的特异性目的旨在通过研究蛋白VII的功能来验证我们的假设， 病毒和细胞基因组。目的1将明确蛋白VII在病毒感染过程中的功能。 生物化学和分子实验将解决蛋白质VII如何利用宿主机制促进 感染性后代的产生。目的2将研究蛋白VII对细胞染色质的影响， 基因组结构基因组学和细胞学方法将确定蛋白质VII与 细胞蛋白质和染色质化的基因组用于抵消抗病毒宿主应答。我们有 组建了一个跨学科的合作团队，以确定这种核心的病毒组蛋白样蛋白颠覆 在一个项目中，细胞先天免疫反应对理解病毒如何引起 改变染色质来克服宿主的防御。

PROJECT SUMMARY The need to evade antiviral immune responses has driven evolution of viral strategies to manipulate host cell chromatin, to control gene expression and subvert cellular defenses. Adenoviruses are ubiquitous viruses that have provided both important model systems for understanding fundamental cellular processes, as well as vectors for therapeutic purposes. Infections by Adenovirus and derived vectors elicit strong innate immune responses, which impact both the course of disease and their effectiveness as vectors for gene delivery and vaccination. Therefore understanding viral proteins that subvert host responses is important for treating infections and improving therapeutic vector applications. Here we focus on Adenovirus protein VII, the major core protein that was previously thought to function exclusively for packaging viral genomes. We discovered that protein VII has unexpected roles on both viral and host genomes during Adenovirus infection. The long- term goal of this project is to decipher how this histone-like viral protein overcomes innate host responses and promotes production of infectious viral progeny. We recently showed that protein VII binds DNA and nucleosomes, possesses post-transcriptional modifications (PTMs) analogous to histones, and accumulates in chromatin during infection. We demonstrated that protein VII can alter the composition of host proteins associated with viral genomes in the nuclei of infected cells, and also sequesters host factors in cellular chromatin. Our central hypothesis is that Adenovirus protein VII mimics histones as part of an insidious strategy that manipulates both viral and cellular chromatin to subvert innate host responses. This novel hypothesis has been formulated on the basis of extensive preliminary data produced in our lab with new tools we have generated to study how protein VII is necessary and sufficient to counter cellular immune responses. The two integrated Specific Aims are designed to test our hypothesis by studying functions of protein VII on viral and cellular genomes. Aim 1 will define functions of protein VII on the viral genome during infection. Biochemical and molecular experiments will address how protein VII exploits host machinery to promote production of infectious progeny. Aim 2 will examine the impacts of protein VII on cellular chromatin and genome architecture. Genomic and cellular approaches will determine how association of protein VII with cellular proteins and the chromatinized genome serves to counteract antiviral host responses. We have assembled an interdisciplinary collaborative team to determine this core viral histone-like protein subverts cellular innate immune responses in a project that has broader implications for understanding how viruses elicit changes in chromatin to overcome host defenses.