Investigating chromatin mechanisms using viral systems

项目摘要 所有真核生物的基因组都被压缩在一个称为染色质的基本组装中， 这是许多疾病和癌症的标志。研究染色质的技术已经有了很大的进步 近年来，使我们能够从线性测序进展到3D染色体构象研究。 然而，越来越清楚的是，染色质状态是动态的，并对扰动作出反应。因此 一个障碍仍然是了解染色质在动态系统中的生物学功能，而不仅仅是在 基线状态。病毒已经进化到接管细胞以产生病毒后代，这必然是劫持 细胞染色质，从而提供了一个理想的动态系统，在其中询问染色质 状态变化。此外，病毒与宿主相互作用的研究带来了双重好处， 在病毒生物学和分子生物学的一些最重要的领域的发现，从剪接， 第53页。由于测序技术的进步，我们现在处于理想的位置，可以采取下一步行动， 在生物学变化的背景下理解染色质。在这项提案中，我们的目标是将尖端的 染色质技术与病毒感染，揭示基本的染色质功能。我们使用两 不同的核复制病毒，腺病毒和疱疹病毒，作为病毒感染的测试案例，以查明 被多种病原体利用的染色质脆弱性。我们已经鉴定出一种病毒包装蛋白， 腺病毒，蛋白VII，导致全球染色质重组，我们将系统地剖析 这种重组发生的机制。我们的初步结果表明，蛋白VII，连同 细胞结合伙伴，可能取代连接组蛋白，从而揭示了一个以前未知的脆弱性， 染色质我们还发现，单纯疱疹病毒将组蛋白变异体macroH2A1整合在 在感染过程中，MacroH2A1已被描述为沉默和激活的标记物。 因此，我们将使用这种情况来解开macroH2A1功能的长期谜团。 完成拟议的研究将产生新的染色质靶点，并促进创新的 治疗癌症、炎症和病毒性疾病。

PROJECT SUMMARY All eukaryotic genomes are compacted in a fundamental assembly called chromatin, the aberrant regulation of which is a hallmark of many diseases and cancers. Technologies to study chromatin have advanced significantly in recent years, allowing us to progress from linear sequencing to 3D chromosome conformation studies. However, it is becoming increasingly clear that chromatin states are dynamic and respond to perturbations. Thus a barrier remains to understanding the biological functions of chromatin in a dynamic system, and not merely at the baseline state. Viruses have evolved to take over the cell to produce viral progeny, necessarily hijacking cellular chromatin for viral benefit, thereby providing an ideal dynamic system in which to interrogate chromatin state changes. Moreover, the study of virus-host interactions has been doubly beneficial by leading to advances in virus biology and to discoveries of some of the most important areas of molecular biology, from splicing to p53. Due to the advances in sequencing technology, we are now ideally positioned to take the next step to understanding chromatin in the context of biological changes. In this proposal, we aim to merge cutting-edge chromatin technology with virus infection to reveal fundamental chromatin functions. We use two different nuclear replicating viruses, adenovirus and herpesvirus, as the test cases for virus infection to pinpoint chromatin vulnerabilities exploited by multiple pathogens. We have identified a viral packaging protein from adenovirus, protein VII, that causes global chromatin reorganization and we will systematically dissect the mechanisms by which this reorganization occurs. Our preliminary results suggest that protein VII, together with cellular binding partners, may replace linker histones thus revealing a previously unknown vulnerability of chromatin. We have also uncovered that herpes simplex virus incorporates the histone variant macroH2A1 on its genome during infection. MacroH2A1 has been described as a marker of both silencing and an activating chromatin, therefore, we will use this scenario to untangle the long-standing enigma of macroH2A1 function. Completion of the proposed studies will generate new chromatin targets and facilitate development of innovative therapies for cancer, inflammation, and viral diseases.