Integration of viral DNA into the genome of the adenovinis type 2-transformed hamster cell line HE5 without loss or alteration of cellular nucleotides

Open Access
Publisher Website
Google Scholar
Abstract
Hamster cell line HE5 has been established from primary LSH hamster embryo cells by transformation with adenovirus type 2 (Ad2) (1). Each cell contains two to three copies of integrated between viral and cellular DNAs. The terminal 10 and 8 nucleotides of Ad2 DNA were deleted at the left and right sites of junction, respectively. The integrated viral DNA had an internal deletion between map units 35 and 82 on the Ad2 genome. At the internal site of deletion, the remaining viral sequences were linked via a GT dinucleotide of unknown origin. From HE5 DNA, the unoccupied sequenced. Part of this sequence was show to be expressed as cytoplasmic RNA in HE5 and primary LSH hamster embryo cells. The viral DNA had been inserted into cellular DNA without deletions, rearrangements or duplications of cellular nucleotides at the site of insertion. Thus, insertion of Ad2 DNA appeared to have been effected by a mechanism different from that of bacteriophage λ in Escherichia coli and from that of retroviral genomes in vertebrates. It was conceivable that the terminal viral protein (4) was somehow involved in integration either on a liner or a circularized viral DNA molecule.