Retrovirus Models of Cellular Post-transcriptional Gene Expression

与项目1、2、5和核心A和B合作，项目3阐明了一种新的翻译 调节轴的逆转录病毒基因组的比较研究。我们的结果蛋白质组学，遗传学和 生物化学分析已经确定了RNA解旋酶A（RHA）在逆转录病毒和细胞凋亡中的新作用。 基因.我们已经证明，RHA特异性地识别一个独特的5'末端转录后控制， 该蛋白质可与5'非翻译区（UTR）的结构特征相结合，以促进高效表达。 帽依赖性翻译起始。我们的生化分析和全基因组翻译的结果 谱分析已经鉴定了需要RHA进行有效翻译的生物学相关基因的子集。 这些PCE候选者中的许多是编码复杂5' UTR的原癌基因，其需要RHA/PCE 互动促进高效翻译。我们确定了RHA在细胞内的基本作用， 翻译控制提供了一个平台，以了解RHA失调是一种肿瘤， 生物标记物。我们的合作研究已经在六种不同的逆转录病毒中确定了PCE活性，包括 HTLV-1;与RHA的相互作用是必要的;这种病毒-宿主相互作用对于有效的HTLV-1是必不可少的。 1翻译。我们对细胞junD中PCE活性的额外鉴定提供了概念验证， 逆转录病毒采用宿主细胞机制来实现有效的RNA表达。我们已经应用了 PCE/宿主相互作用以刺激逆转录病毒载体中的蛋白质输出;这项创新适用于广泛的 一系列基因表达系统。我们的基本见解涉及RHA作为一个综合效应器， 从转录到翻译的基因表达连续体，并协调病毒和细胞基因 表情初始供资期的结果与共同的项目编制补助目标密不可分， 了解病毒与宿主的相互作用和基因调控机制。这一高度关注的主要焦点 交互式的延续是理解RHA/PCE平移控制轴的范围和调节 在逆转录病毒和宿主基因中。具体来说，我们假设RHA调节子是一个可诱导的翻译控制 选择的基因的机制，其动态调节有助于细胞的改变， 导致转化和副肿瘤性疾病的微环境。我们的三个相互关联的目标是： 目标1。为了表征RHA基因表达的基本特征和细胞内定位， 周期进展;目标2.研究RHA翻译活性在破骨细胞活性和Tax肿瘤中的作用 目标3.评估junD PCE与逆转录病毒相关的基本特征、结构/功能 PCE数据库。长期目标是将RHA转录后调节子的知识应用于 开发载体和小分子，以选择性地调节参与肿瘤的RHA应答基因。 转化、副肿瘤疾病和逆转录病毒感染。

In collaboration with Projects 1, 2, 5 and Cores A and B, Project 3 has elucidated a new translation regulatory axis by comparative studies of retroviral genomes. Our results of proteomic, genetic and biochemical analysis have identified a novel role for RNA helicase A (RHA) in both retroviral and cellular genes. We have shown that RHA specifically recognizes a unique 5' terminal post-transcriptional control element (PCE) and neutralizes structural features of the 5' untranslated region (UTR) to facilitate efficient cap-dependent translation initiation. Our results of biochemical analyses and genome-wide translation profiling have identified a subset of biologically-related genes that require RHA for their efficient translation. Many of these PCE candidates are proto-oncogenes encoding a complex 5' UTR, which require RHA/PCE interaction to promote efficient translation. Our identification of the fundamental role of RHA in cellular translational control provides a platform to understand the observation that RHA dysregulation is a tumor biomarker. Our collaborative studies have identified PCE activity in six divergent retroviruses, including HTLV-1; that interaction with RHA is necessary; and this virus-host interaction is essential for efficient HTLV- 1 translation. Our additional identification of PCE activity in cellular junD provided proof-of-concept that retroviruses have adopted a host cell mechanism to achieve efficient RNA expression. We have applied the PCE/host interaction to stimulate protein output in retroviral vectors; this innovation is applicable to a wide array of gene expression systems. Our fundamental insights implicate RHA as an integrative effector in the continuum of gene expression from transcription to translation and in coordinating viral and cellular gene expression. The outcomes of the initial funding period are inextricably linked to the common PPG goal to understand virus-host interactions and mechanisms of gene regulation. A primary focus of this highly interactive Continuation is to understand the scope and regulation of the RHA/PCE translational control axis in retroviral and host genes. Specifically, we postulate the RHA regulon is an inducible translational control mechanism of selected genes, whose dvsregulation contributes to alterations of the cellular microenvironment leading to transformation and paraneoolastic disease. Our three interrelated Aims are: Aim 1. To characterize essential features of RHA gene expression and cytoplasmic localization during cell cycle progression; Aim 2. To examine role of RHA translational activity in osteoclast activity and Tax tumor model; Aim 3. To assess the essential features structure/function of junD PCE in relation to the retrovirus PCE database. Long-term objectives are application of knowledge of the RHA post-transcriptional regulon to develop vectors and small molecules to selectively modulate RHA responsive genes involved in neoplastic transformation, paraneoplastic disease and retrovirus infection.