HAMMERHEAD RIBOZYME TRAGETED TO MURINE LEUKEMIA VIRUS

小鼠白血病病毒（MuLV）是从中国南方野生小鼠中分离到的一种病毒。 加州。 这些非急性白血病病毒属于 C逆转录病毒。 他们没有任何已知的致癌基因，也不能 在培养中转化细胞。 然而，它们会导致脾淋巴瘤， 以及易感的近交系小鼠。 这些野生小鼠MuLV有许多 与人类T细胞白血病病毒相似 作为人类的模型 淋巴瘤/白血病，野生小鼠MuLV诱导的脾淋巴瘤密切相关 类似于儿童急性淋巴细胞白血病。 的总体目标 目前研究是开发一种抗逆转录病毒方法， 会引起病毒RNA的特异性切割，抑制病毒感染 在培养的细胞和病毒诱导的小鼠脾淋巴瘤。 最近发现的核酶表明，特定的RNA分子可以 像酶一样工作并降解目标RNA分子。 其中， 核酶，锤头状核酶催化结构域似乎是 最简单的一个，催化中心可以很容易地并入 反义RNA。 核酶针对特定RNA的特异性靶向 然而，在细胞内部，似乎构成了一个主要问题。 拟议 研究中，锤头状核酶将被设计、合成并靶向 通过利用psi序列（逆转录病毒 RNA包装信号）。 预计 这样的序列将共定位核酶和MuLV基因组RNA 在受感染细胞的细胞质微环境中， 切割病毒RNA。 另外，这样的核酶构建体将 也可以掺入小鼠的种系中。 保护转基因生物 小鼠抗病毒攻击和轻度小鼠MuLV 10A 1诱导 因此，淋巴瘤形成将为延长这一时间提供合理的基础。 治疗逆转录病毒相关的人类癌症，如T- 细胞白血病和逆转录病毒引起的类似疾病，如获得性 免疫机能丧失综合症（艾滋病）

Murine leukemia viruses (MuLV) have been isolated from the wild mice of So. California. These non-acute leukemia viruses belong to the family of type C retroviruses. They do not possess any known oncogene and are unable to transform cells in culture. However, they cause splenic lymphoma in wild, as well as, susceptible inbred mice. These wild mouse MuLVs have many similarities with human T-cell leukemia Virus. As a model for human lymphoma/leukemia, the wild mouse MuLV-induced splenic lymphoma closely resembles childhood acute lymphoblastic leukemia. The overall objective of the present investigation is to develop an anti-retroviral approach which will cause specific cleavage of the viral RNA, inhibiting virus infection in a cultured cell and virus-induced splenic lymphoma in mice. The recent discovery of ribozymes has shown that specific RNA molecules can work as enzymes and degrade target RNA molecules. Of t he various ribozymes, the hammerhead ribozyme catalytic domain appears to be the simplest one, and the catalytic center can be easily incorporated into anti-sense RNA. Specific targeting of a ribozyme against a particular RNA inside the cell, however, appears to pose a major problem. In the proposed study, a hammer-head ribozyme will be designed, synthesized, and targeted against the MuLV RNA by taking advantage of the psi sequence (retroviral RNA packaging signal) of an MuLV-based retroviral vector. It is expected that such a sequence will colocalize the ribozyme and the MuLV genomic RNA in the cytoplasmic micro-environment of the infected cell, aiding trans- cleavage of the viral RNA. Additionally, such a ribozyme construct will also be incorporated in the germline of mice. Protection of the transgenic mice against virus challenge and mild mouse MuLV 10A1-induced lymphomagenesis would thus provide a rational basis for extending this strategy for the treatment of retrovirus-associated human cancer such as T- cell leukemia and retrovirus induced allied diseases like acquired immunodeficiency syndrome (AIDS)