Host factors in innate immunity and retroelement control

项目摘要/摘要 基于干扰素的先天免疫系统是抵御病毒感染和癌症的第一道防线。 在不断的选择压力下，它已经演变成快速而准确的行动。然而，高度的警觉性 随之而来的是代价--有时自己的分子被错误地认为是外来的，这导致了 干扰素产生异常。因此，这一体系处于微妙的平衡之中。 从对自身免疫性疾病的研究中，我们知道内源性逆转录因子是 “外来”核酸，当控制不当时，它们会引发干扰素的异常产生。但 内源性逆转录酶在先天免疫中也起着重要的有益作用。有证据表明， 维持系统的张力，它们为细胞进行有效的抗病毒反应做好准备。它们还充当内部 当癌症中转录失调时发出警报，提醒免疫系统有危险。几个 逆转录酶限制因素是已知的，其机制也已被研究；然而，可能存在 关于逆行元素是如何控制的，以及它们如何影响先天，我们还有很多不知道的东西 豁免权。 该项目的目标是确定与逆转录元件控制有关的新宿主因子，并获得 对MOV10的S作用机制的机械论洞察。MOV10是一个强有力的反转录元件限制因子，并且 有证据表明，它可能通过一种鲜为人知的小RNA机制来抑制逆转录元件。如果是真的， 识别MOV10功能所需的主机因素可以提供对MOV10之间相互作用的独特见解 主要由脊椎动物和更古老的以小RNA为基础的蛋白质为基础的干扰素系统 许多其他物种使用的抗病毒防御机制。 我们将采取的方法利用最先进的CRISPR筛查技术来敲除每一个 并确定限制完整LINE-1复制的宿主因素 反元素。我们将使用同样的方法来识别MOV10功能所需的宿主蛋白。 后者将提供有用的机械性见解，我们将使用额外的逆转录病毒进行更详细的探索 (HIV-1)和反转录元件(Alu反转录转座子)工具。 我们希望这项工作将提供新的见解，拓宽我们对逆行元素的理解 生物学和先天免疫。这些结果可能会改变我们对抗病毒机制的看法， 自身免疫力和癌症。

Project Summary/Abstract The interferon (IFN)-based innate immune system is the first line of defense against viral infections and cancer. Under constant selective pressure, it has evolved to act quickly and accurately. Yet heightened alertness comes with a price—occasionally self molecules are improperly recognized as foreign and this leads to aberrant IFN production. Thus, the system exists in a delicate balance. From studying autoimmune disorders, we know that endogenous retroelements are a major source of “foreign” nucleic acids and that they trigger aberrant IFN production when improperly controlled. But endogenous retroelements also play important beneficial roles in innate immunity. There's evidence that by maintaining tension in the system, they prime cells for effective antiviral responses. They also act as internal alarms to alert the immune system of danger when transcription is dysregulated in cancer. Several retroelement restriction factors are known and their mechanisms have been studied; however, there are likely more and there is much we don't know about how retroelements are controlled and how they affect innate immunity. The goals of this project are to identify novel host factors involved in retroelement control and to gain mechanistic insight into MOV10's mechanism of action. MOV10 is a potent retroelement restriction factor, and there is evidence that it may inhibit retroelements by a poorly understood small RNA mechanism. If true, identifying host factors required for MOV10 function could provide unique insights into the interplay between the protein-based IFN system used primarily by vertebrates and the more ancient small RNA-based mechanism of antiviral defense used by many other species. The approach that we'll take utilizes state-of-the-art CRISPR screening technology to knockout every gene in the human genome and identify host factors that restrict the replication of an intact LINE-1 retroelement. We will use this same approach to identify host proteins that are required for MOV10 function. The latter will provide useful mechanistic insights that we will explore in more detail using additional retroviral (HIV-1) and retroelement (Alu retrotransposon) tools. We expect that this work will provide new insights that will broaden our understanding of retroelement biology and innate immunity. These results may change the way we think about antiviral mechanisms, autoimmunity, and cancer.