We developed highly sensitive shuttle vector systems for detection of mutations formed in human cells using autonomously replicating derivatives of Epstein-Barr virus (EBV). EBV vectors carrying the bacterial lacI gene as the target for mutation were established in human cells and later returned to Escherichia coli for rapid detection and analysis of lacl mutations. The majority of the clonal cell lines created by establishment of the lacl-EBV vector show spontaneous LacI frequencies of less than 10-5 and are suitable for studies of induced mutation. The ability to isolate clonal lines represents a major advantage of the EBV vectors over transiently replicating shuttle vectors (such as those derived from simian virus 40) for the study of mutation. The DNA sequence changes were determined for 61 lacI mutations induced by exposure of one of the cell lines to N-nitroso-N-methylurea. A total of 33 of 34 lacI nonsense mutations and 26 of 27 missense mutations involve G C to A. T transitions. These data provide support for the mutational theory of cancer.

Genomic sequence analysis is usually performed with the help of specialized software packages written for molecular biologists.

6enet1c rearran9ement5 and 9ene amp11f1cat10n 1n E5cher1ch1a c011: DNA 5e4uence5 at the juncture5 0f amp11f1ed 9ene fu510n5 5u5an K. Wh0r15key, Van-Ha N9h1em, Pha1k-M001 Le0n9, Jean-M1che1 Ma550n, and Jeffrey H. M111er

No abstract

No abstract