VECTORS, CELL LINES AND THEIR USE IN OBTAINING EXTENDED EPISOMAL MAINTENANCE REPLICATION OF HYBRID PLASMIDS AND EXPRESSION OF GENE PRODUCTS

摘要

This disclosure shows that the BPV-1 E2 protein-dependent minichromosome maintenance element (MME) comprised of E2 multimeric binding sites can provide the stable maintenance replication function to the mouse polyomavirus (PyV) core origin plasmids in the presence of BPV-1 E2 protein and PyV large T-antigen (LT). MME dependent plasmids are lost with the frequency of 6% per generation. Significanly long stable maintenance replication can also be provided without selection pressure. We also demonstrate that PyV core origin maintenance function/replication activation could be provided by Epstein-Barr virus Family of repeats and EBNA1 protein. The maintenance of the Polyomavirus core origin plasmid was characterized by 13% loss of the plasmid during one cell generation in the case of EBV FR harboring plasmids. Our data clearly indicate that maintenance functions from different viruses can provide segregation/partitioning function to different heterologous origins in variety of cells and can be used in expression of gene products.