Mechanisms of HTLV-1 p30 in Transcription and DMA Repair

通过逆转录病毒研究获得的见解建立了细胞生物学的基本范式，包括 淋巴细胞活化和增殖的机制。在P01 CA 100730的项目1中，我们寻求继续 研究人类嗜T淋巴细胞病毒1型（HTLV-1），一种复杂的逆转录病毒的基本问题 导致成人T细胞淋巴瘤/白血病（ATL）。HTLV-1编码典型的gag、pol和env基因 产品，和独特的基因编码在其pX区域。在这个高度协作的PPG中，我们开创了 HTLV-1蛋白在体内病毒复制和淋巴细胞活化中的作用的检查， 是病毒传播和细胞转化的重要前提。该项目的重点是从 这些研究集中在我们提出的对HTLV-1的pX ORF II编码的p30的研究。这 核/核仁蛋白与转录因子具有同源性，并含有G/SK共有乙酰化 网站.我们与绿色、拉特纳和鲍里斯-劳里博士的合作研究（项目2、3、5、核心A、B和C） 这一PPG提供了第一个证据，证明p30是病毒在动物中建立感染所必需的， 作为转录因子，受到乙酰化的积极影响并结合共激活因子的KIX结构域， p300。我们现在提供了令人兴奋的新数据，这些数据表明p30参与了DMA损伤/修复信号传导， 细胞周期紊乱并可能促进病毒整合。我们的数据表明，HTLV-1在一种新的 调节细胞环境以有利于细胞存活并平衡病毒反式激活影响的方式 (i.e.,税）以允许病毒持续存在。在本PPG的下一阶段，我们提供相互依赖的方法， 通过比较试验确定HTLV-1 p30和HTLV-2 p28（项目2）的作用， 转录和转录后控制参数。我们为此制定了具体目标 项目1的竞争性更新：1）定位HTLV-1 p30的重要结构基序， T淋巴细胞中的转录调控和DNA损伤/修复信号，2）确定翻译后的作用 HTLV-1 p30介导的转录调控和DNA损伤/修复中的修饰 T淋巴细胞中的信号传导，和3）测试在p30介导的转录中重要的结构基序 早期病毒表达时空分布的调控和DNA损伤/修复信号 在具有pX ORF II中的选择性突变的HTLV-1分子克隆的兔中。我们的长期目标是 了解逆转录病毒，如HTLV-1如何改变T细胞生理学，从而深入了解 细胞转化的早期阶段和治疗干预的新靶点。

Insights gained through the study of retroviruses have established basic paradigms of cell biology, including mechanisms of lymphocyte activation and proliferation. In Project 1 of P01 CA100730 we seek to continue to investigate fundamental questions of Human T-lymphotropic Virus Type 1 (HTLV-1), a complex retrovirus that causes adult T-cell lymphoma/leukemia (ATL). HTLV-1 encodes typical gag, pol, and env gene products, and unique genes encoded in its pX region. In this highly collaborative PPG, we have pioneered the examination of the role of HTLV-1 proteins in viral replication in vivo and in lymphocyte activation, an important antecedent to virus transmission and cell transformation. The focus of this project emerged from these studies and concentrates our proposed studies on p30 encoded in pX ORF II of HTLV-1. This nuclear/nucleolar protein has homology to transcription factors and contains G/SK consensus acetylation sites. Our collaborative studies with Drs. Green, Ratner, and Boris-Lawrie (Projects 2, 3, 5, Cores A, B, & C) of this PPG provided the first evidence that p30 is required by the virus to establish infection in animals, acts as a transcription factor, is positively influenced by acetylation and binds the KIX domain of the co-activator, p300. We now provide exciting new data that implicate p30 in DMA damage/repair signaling that results in cell cycle perturbation and likely promote viral integration. Our data indicate that HTLV-1 uses p30 in a novel manner to modulate the cellular environment to favor cell survival and balances the influence of viral transactivation (i.e., Tax) to allow viral persistence. In our next phase of this PPG, we provide interdependent approaches to identify the roles of HTLV-1 p30 and HTLV-2 p28 (Project 2) by comparative testing of essential transcriptional and post-transcriptional control parameters. We have focused specific aims for this competitive renewal of Project 1 on: 1) Localize important structural motifs of HTLV-1 p30 that mediated transcriptional regulation and DNA damage/repair signaling in T lymphocytes, 2) Determine the role of posttranslation modifications in HTLV-1 p30 -mediated transcriptional regulation and DNA damage/repair signaling in T lymphocytes, and 3) Test structural motifs important in p30 -mediated transcriptional regulation and DNA damage/repair signaling in the spatial and temporal distribution of early virus expression in rabbits with HTLV-1 molecular clones with selective mutations in pX ORF II. Our long-term goal is to understand how retroviruses, like HTLV-1 alter T cell physiology and thereby gain insight into mechanisms of the early phases of cell transformation and new targets of therapeutic intervention.