REPLICON CONTROL IN NORMAL AND TRANSFORMING CELLS

细小病毒与宿主细胞的相互作用被用作探针 真核细胞分化、DNA复制和衰老。我们会 探索细小病毒早期和晚期启动子的特性以及 他们之间的互动。早期启动子产生一种基因产物， 正向调节晚期启动子。机制和顺序 参与这一反式激活将被研究。早期的细小病毒 启动子将被测试对宿主细胞调节蛋白的依赖性 并分离出适合克隆这种蛋白基因的细胞系。 在成纤维细胞分化的末期，衰老的细胞 对细小病毒感染产生抵抗力，这些细胞将被测试 限制病毒早期启动子活性。

The interaction of parvovirus with its host cell is being used as a probe of eukaryotic cell differentiation, DNA replication, and aging. We will explore the properties of parvovirus early and late promoters and the interaction between them. The early promoter produces a gene product that positively regulates the late promoter. The mechanisms and sequences involved in this trans-activation will be studied. The parvovirus early promoter will be tested for dependence on a host cell regulatory protein and cell lines suitable for cloning the gene for such a protein isolated. In the terminal stages of fibroblast differentiation, the senescing cells become resistant to parvovirus infection and these cells will be tested for restriction of virus early promoter activity.