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The Harold Varmus Papers

For the ICRF Annual Report, 1979: III. Co-Transfection with Papovavirus and Retrovirus DNA Using Recombinant DNA Prepared In vitro pdf (81,149 Bytes) transcript of pdf
For the ICRF Annual Report, 1979: III. Co-Transfection with Papovavirus and Retrovirus DNA Using Recombinant DNA Prepared In vitro
Varmus here provided an overview of his research during his sabbatical year at the Imperial Cancer Research Fund in London in 1978-79. His studies focused on the ways in which retroviruses cause mutations of genes, including the genes deposited by other retroviruses that had previously infected the cell.
Item is a photocopy.
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1 (81,149 Bytes)
Varmus, Harold
[Fried, Mike]
Original Repository: University of California, San Francisco. Archives and Special Collections. Harold E. Varmus Papers
Reproduced with permission of the Regents of the University of California.
Medical Subject Headings (MeSH):
DNA, Recombinant
Exhibit Category:
Retroviruses and the Genetic Origins of Cancer, 1970-1993
Metadata Record For the ICRF Annual Report, 1979: I. The Rare Revertants of an ASV-Transformed Rat Cell Have Lost Proviral DNA or Bear Mutations in SRC (1979) pdf (98,046 Bytes) transcript of pdf
Metadata Record For the ICRF Annual Report, 1979: II. Retroviruses as Mutagens: Isolation of Revertants with Deletions and/or Insertions in the ASV Provirus in B31 Cells after Superinfection with MuLV (1979) pdf (84,244 Bytes) transcript of pdf
Box Number: 1
Folder Number: 17
Unique Identifier:
Document Type:
Physical Condition:
Series: UCSF Collections
SubSeries: Collection Number MSS 84-25
SubSubSeries: Correspondence, 1971-1984
Folder: Correspondence, 1979
H.E. Varmus
A.M.F. Fried
The introduction of purified pieces of functionally interesting DNA into eukaryotic cells is an important means to deciphering genetic regulation in higher organism. In many cases, the DNA of interest does not encode functions for which genetic selection procedures are available. We have developed a procedure for circumventing this difficulty by linking transforming regions of a papovavirus genome to pieces of retroviral DNA lacking selectable markers. The approach has the additional virtues of not requiring expression of the retrovirus DNA and of allowing an assessment of signals thought to be important in the integration and expression of the two types of viral genomes.
We joined two fragments of polyoma virus DNA, which together contain an intact early region, and a fragment of transformation-defective avian sarcoma virus (ASV) DNA, which contains the env gene of ASV and sequences from the termini of viral RNA. (The ASV DNA was provided by Dr. W. DeLorbe of the University of California, San Francisco, after cloning in [lambda]gt WES.) The desired recombinant molecule was isolated as a linear species from other products of ligation of the three fragments by digestion with the restriction endonuclease BamHI and preparative gel electrophoresis. After confirming the structure of the recombinant DNA, it was used to transfect rat-1 cells with the calcium phosphate technique. Most of the resulting transformed cells contained from 1 to 3 copies of recombinant DNA. Napping studies indicated that the recombinant molecules did not circularize during transfection, since the integrated copies were approximately co-linear with the transfecting DNA, though lacking small regions from the termini of the recombinant molecules. Preliminary analysis of the ASV-specific RNA in several transformed lines indicates that few or no stable transcripts are synthesized from this region of the recombinant DNA's (tests performed by S. Ortiz, University of California, San Francisco). The significance of these observations with respect to signals for integration and expression of retroviral DNA is being evaluated by application of these methods to other combinations of molecules and host cells.
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