VIRAL SMALL RNPS--ROLES IN CELL TRANSFORMATION

病毒小 RNPS——在细胞转化中的作用

• 批准号: 6268827
• 负责人: JOAN A. STEITZ
• 金额: $ 16.76万
• 依托单位: YALE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-05-01 至 1999-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6268827
• 关键词: Epstein Barr virus; cell cycle; genetic translation; messenger RNA; molecular cloning; neoplasm /cancer genetics; nucleic acid sequence; ribonucleoproteins; ribosomal proteins; transfection /expression vector; viral carcinogenesis; virus protein

Small RNPs present in cells transformed by certain primate Herpesviruses are assembled from virus-encoded small RNAs and host protein components. The two EBERs (Epstein Barr encoded RNAS) of EBV tightly bind the cellular lupus antigen La (50 kd), while the four newly discovered HSURs (Herpes saimiri U-like RNAS) acquire 5'-m3G caps and associate with proteins common to the snRNPs responsible for splicing and other premessenger RNA processing reactions in mammalian cell nuclei. Both the EBERs and HSURs are localized in the nucleus and are among the few viral gene products expressed in transformed lymphocytes. Our long term goals are to understand how these viral small RNPs contribute to the transformed state and how t cell in turn controls their biogenesis. To achieve these goals we propose the following strategies: 1) We will ask, using in fl= assays and immunoprecipitation, whether EBERs might regulate the activity of the interferon-induced 2',5'-oligoA synthetase, since they do not have the same inhibitory effect as VAI on the activity of the interferon-induced protein kinase. We will construct EBER affinity columns to identify and subsequently characterize nuclear proteins that bind EBERS. 2) We will ask whether the high abundance of EBERs in EBV-transformed cells serves to ' maintain high levels of important cellular small RNAs (tRNAs, 5S) because of the sequestration of a large fraction of the cellular La protein. We will further probe La's function in transcription termination in vitro. 3) We will identify and characterize the transcription factors that bind to regulatory sequences upstream of the EBER genes (and the genes for HVP1 and 2 RNAs of Herpesvirus papio). Those that are also involved in transcription of cellular and viral oncogenes will be studied to ascertain co-regulation by phosphorylation, extracellular signals, protein interaction, etc. 4) The function of HSURs will be probed based on the assumption that they act in polyadenylation. Long-elusive comparable host-RNAs will be sought using HSUR probes. 5) Other primate Herpesviruses will be examined for the presence of novel small RNAs using various patient autoantibodies.

存在于某些灵长类疱疹病毒转化的细胞中的小RNP 是由病毒编码的小RNA和宿主蛋白组分组装而成的。 EB病毒的两个EBER（Epstein巴尔编码的RNA）紧密结合细胞内的 狼疮抗原La（50 kd），而四个新发现的HSUR（疱疹 saimiri U样RNAS）获得5 '-m3 G帽并与常见蛋白质结合 负责剪接的snRNP和其他前信使RNA 在哺乳动物细胞核中处理反应。EBER和HSUR都是 位于细胞核中，是少数几种病毒基因产物之一 在转化的淋巴细胞中表达。我们的长期目标是了解 这些病毒小RNP如何促成转化状态，以及如何 细胞反过来控制它们的生物合成。 为了实现这些目标，我们提出了以下策略：1）我们将 问，在fl=测定和免疫沉淀中使用，EBER是否可能 调节干扰素诱导的2 ′，5 ′-oligoA合成酶的活性， 因为它们不具有与VAI相同的对以下活性的抑制作用： 干扰素诱导的蛋白激酶。我们将构建EBER亲和力 柱来识别并随后表征核蛋白， 绑定EBERS。2)我们会问， EB病毒转化的细胞用于“维持高水平的重要的 细胞小RNA（tRNAs，5S），因为一个大的 细胞La蛋白的一部分。我们将进一步探讨La在 体外转录终止。 3)我们将识别并描述 结合到转录因子上游的调节序列的转录因子， EBER基因（以及乳头疱疹病毒HVP 1和2 RNA的基因）。那些 也参与细胞和病毒致癌基因的转录 将被研究以确定通过磷酸化的共调节， 4）HSURs的功能 将基于它们在多聚腺苷酸化中起作用的假设进行探测。 将使用HSUR探针寻找长期难以捉摸的可比宿主RNA。第五章） 将检查其他灵长类疱疹病毒是否存在新的 使用各种患者自身抗体的小RNA。