RETROVIRAL ANTI-SENSE RNA--CELLULAR AND VIRAL RESPONSES

反义RNA提供了一种特异性阻断 通过与所述基因形成双链体来表达给定基因， 靶RNA。 这种技术也被用于阻止 逆转录病毒的复制含有与 细胞RNA 因此，这项技术提供了一种潜在的治疗方法， 特异性阻断致癌病毒表达策略 基因产物和/或致癌逆转录病毒的复制。 使用 然而，这项技术的应用受到了限制，因为 互补RNA阻断基因表达的机制 或逆转录病毒复制的研究知之甚少。 更好的 理解反义RNA阻断 基因表达和逆转录病毒复制可能允许更多的 这项技术的有效应用。 模型系统使用 逆转录病毒载体能够表达与 已经开发了细胞序列。 产生RNA的载体 与同一靶mRNA的不同区域互补 被隔离了 这些载体产生反义 有效阻断表达的转录物， 靶mRNA比许多靶mRNA有效大约100倍 以前报道过，它们是对一个区域的补充， mRNA以前不被认为是一个好的 目标，他们显然阻止表达的 互补的mRNA的机制，这还没有被 先前描述的。 这项提案的目的是利用 该模型定义了这种反义 系统阻断其互补细胞mRNA的表达， 以确定互补的细胞RNA对 逆转录病毒的复制。 研究中描述了一种 一系列逆转录病毒构建体将用于1）定义更多 正是互补RNA的区域参与了 体内和体外双链体形成，2）不同RNA的影响 转录物对双链体形成和稳定性的影响，以及3） 有效的反义结构阻断 互补细胞mRNA的翻译。 实验 描述了使用该相同的模型， 以下问题：1）产生RNA的细胞 与逆转录病毒的互补， 感染了这种逆转录病毒 如果是，影响程度的因素是什么？ 这种抵抗？2)互补的细胞RNA 影响能够感染其他人的病毒的包装和释放 细胞？

Anti-sense RNA provides a means for specifically blocking the expression of a given gene through formation of a duplex with the target RNA. This technique has also been used to block replication of retroviruses containing RNA complementary to cellular RNA. Thus, this technique offers a potential therapeutic strategy for specifically blocking expression of an oncogenic viral gene product and/or replication of an oncogenic retrovirus. Use of this technology, however, has been limited because the mechanisms by which complementary RNA blocks gene expression or retroviral replication are poorly understood. A better understanding of mechanisms by which anti-sense RNA blocks gene expression and retroviral replication may permit more effective applications of this technology. A model system using retroviral vectors capable of expressing RNA complementary to cellular sequences has been developed. Vectors producing RNA complementary to different regions of the same target mRNA have been isolated. Those vectors producing anti-sense transcripts which are effective in blocking expression of the target mRNA are approximately 100 x more potent than many previously reported, they are complementary to a region of the mRNA which has previously not been considered to be a good target, and they apparently block expression of the complementary mRNA by a mechanism which has not been described previously. The purpose of this proposal is to exploit this model to define the mechanism(s) by which this anti-sense system blocks expression of its compementary cellular mRNA and to determine what effect the complementary cellular RNA has on replication of the retrovirus. Studies are described in which a series of retroviral constructs will be used to 1) define more precisely the regions of the complementary RNAs participating in duplex formation in vivo and in vitro, 2) effects of different RNA transcripts upon duplex formation and stability, and 3) mechanisms by which effective anti-sense constructs block translation of complementary cellular mRNA's. Experiments using this same model are described which will address the following questions: 1) Are cells which produce RNA complementary to that of the retrovirus less susceptible to infection by this retrovirus? If so, what factors affect the extent of this resistance? 2) Do complementary cellular RNAs adversely affect packaging and release of viruses capable of infecting other cells?