Sequence of the junction in adenovirus 2-SV40 hybrids: examples of illegitimate recombination (original) (raw)
Related papers
The structure and expression of two defective adenovirus 2/simian virus 40 hybrids
Journal of Molecular Biology, 1978
Two new defective adenovirus 2/simian virus 40 hybrids (Ad2+Dl and Ad2+D2) have been isolated from the population known as Ad2+ +HEY . The structure of their genomes has been determined by analysis with restriction enzymes, hybridization and electron microscopy. The DNA of Ad2 +Dl is almost equal in size to that of its helper, adenovirus 2. It contains an insertion of simian virus 40 (SV40) sequences 3.2 x 1 O3 bases long in place of the 3.5 x lo3 base segment of adenovirus 2 DNA which maps between 0.64 and 0.74 fractional genome lengths from the left end of the viral DNA. The insertion which encompasses the entire early region of the SV40 genome, comprises the segment of DNA lying between positions 71 and 10: it is oriented with the sequences coding for the carboxy terminus of the A gene protein to the left.
Journal of Virology, 1973
Two of the five nondefective adenovirus 2 (Ad2)-simian virus 40 (SV40) hybrids induce SV40 transplantation resistance in immunized hamsters. These two hybrids, Ad2 + ND 2 and Ad2 + ND 4 , contain 32 and 43% of the SV40 genome, respectively. The pattern of induction of SV40 transplantation antigen (TSTA) by the various hybrids differentiates TSTA from both SV40 U and T antigens. Since the SV40 RNA induced by both these hybrids is early SV40 RNA, these findings confirm that TSTA is an early SV40 function. By combining available data on SV40 antigen induction by these hybrids with electron microscopy heteroduplex mapping studies, the DNA segment responsible for the induction of SV40 TSTA can be inferred to lie in the region between 0.17 and 0.43 SV40 units from the site on the SV40 chromosome cleaved by E. coli R 1 restriction endonuclease.
Patch homologies and the integration of adenovirus DNA in mammalian cells
The EMBO Journal
The hamster cell line HE5 has been derived from primary hamster embryo cells by transformation with human adenovirus type 2 (Ad2). Each cell contains 2-3 copies of Ad2 DNA inserted into host DNA at apparently identical sites. The site of the junction between the right terminus of Ad2 DNA and hamster cell DNA was cloned and sequenced. The eight [corrected] right terminal nucleotides of Ad2 DNA were deleted. The unoccupied cellular DNA sequence in cell line HE5 , corresponding to the site of the junction between Ad2 and hamster cell DNA, was also cloned; 120-130 nucleotides in the cellular DNA were found to be identical to the cellular DNA sequence in the cloned junction DNA fragment, up to the site of the junction. The unoccupied and the occupied cellular DNAs and the adjacent viral DNA exhibited a few short nucleotide homologies. Patch homologies ranging in length from dodeca - to octanucleotides were detected by computer analyses at locations more remote from the junction site. Whe...
Nucleic Acids Research, 1982
The hamster cell line CLAC1 originated from a tumor induced by injecting human adenovirus type 12 (Ad12) into newborn hamsters. Each cell contained about 12 copies of viral DNA colinearly integrated at two or three different sites. We have cloned and sequenced a DNA fragment comprising the site of junction between the left terminus of Ad12 DNA and cellular DNA. The first 174 nucleotides of Ad12 DNA were deleted at the site of junction. Within 40 nucleotides, there were one tri-, two tetra-, one penta-, and one heptanucleotide which were identical in the 174 deleted viral nucleotides and the cellular sequence replacing them. In addition, there were patch-type homologies ranging from octa-to decanucleotides between viral and cellular sequences. There is no evidence for a model assuming adenovirus DNA to integrate at identical cellular sites. The cellular DNA sequence corresponding to the junction fragment was cloned also from BHK21(B3) hamster cells and sequenced. Up to the site of linkage with viral DNA, this middle repetitive cellular DNA sequence was almost identical with the equivalent sequence from CLAC1 hamster cells. Taken together with the results of previously published analyses (11, 12), the data suggest a model of viral (foreign) DNA integration by multiple short sequence homologies. Multiple sets of short patch homologies might be recognized as patterns in independent integration events. The model also accounts for the loss of terminal viral DNA sequences.
Studies on the nature of the linkage between the terminal protein and the adenovirus DNA
Biochemical and Biophysical Research Communications, 1980
The termini of human adenovirus types 7 and 2 DNA extracted from the virions using pronase and protease K are covalently linked to peptides that contain tyrosine residue(s). The peptide attached to each terminus can be labeled with [1251] i __n_ vitro. The linkage between the peptide moiety and the terminal nucleotide is sensitive to snake venom phosphodiesterase, Aspergillus nuelease S I and microeoccal nuelease. The available data suggest that the peptide is linked to the terminal nucleotide of these DNA molecules through a phosphodiester bond. Human Ad DNA extracted from the virion using guanidine hydrochloride is a linear, duplex molecule containing a protein of 55,000 daltons tightly associated with its termini (I-8). Treatment of the Ad virion or the DNA-protein complex with a protease results in a linear DNA whose 5' ends were blocked to digestion with 5' exonucleases and phosphorylation by phosphatase, polynucleotide kinase and [y_32p] ATP (9). However, the 3'-specific E. coli exonuclease III acts on such viral DNA molecules (10,11,12). These observations suggested that the 55K protein bound (presumably covalently) to the 5' termini leaves a residual amino acid or peptide attached to the 5' terminal nucleotide upon treatment with protease K or pronase. The 5' terminal nueleotide has been shown to be a dC residue (9,13-15). In this communication, we wish to report that the viral DNA isolated from Ad 2 or Ad 7 serotype by treatment with protease K and/or pronase can be specifically labeled at the 5' termini with [125I] using chloramine-T as the oxidizing agent (16). Although under some circumstances iodine may react with sulf
Proceedings of the National Academy of Sciences, 1972
The complementary DNA strands of the nondefective adenovirus 2 (Ad2)-simian virus 40 (SV40) hybrid virus, Ad2 + ND 1 , were separated by isopycnic banding in a CsCl density gradient in the presence of synthetic polyribonucleotides. Separated strands were used in DNA-RNA hybridization reactions with RNA from cells productively infected by Ad2 or SV40, and with complementary SV40 RNA transcribed asymmetrically in vitro . About five times as much Ad2 RNA hybridized to the light stand of Ad2 + ND 1 as to the heavy strand. Complementary RNA and early SV40 RNA (RNA synthesized before viral DNA replication) had significant homology only with the light strand. Only half as much of a preparation of RNA synthesized before and after viral DNA replication (early-plus-late SV40 RNA) hybridized to the light strand as to the heavy strand. These results indicate that templates for both late and early SV40 RNA are present in Ad2 + ND 1 . Therefore, the small SV40 segment within this virus (10-18% of...