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The U3 Portion of Feline Leukemia Virus DNA Identifies Horizontally Acquired Proviruses in Leukemic Cats

Casey, James W. and Roach, Arthur and Mullins, James I. and Burck, Kathy Bauman and Nicolson, Margery O. and Gardner, Murray B. and Davidson, Norman (1981) The U3 Portion of Feline Leukemia Virus DNA Identifies Horizontally Acquired Proviruses in Leukemic Cats. Proceedings of the National Academy of Sciences of the United States of America, 78 (12). pp. 7778-7782. ISSN 0027-8424.

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The presence and location of DNA sequences related to the U3 and U5 portions of the infectious exogenous feline leukemia virus (FeLV) long terminal repeat (LTR) in various cat DNAs have been determined by hybridization experiments. In uninfected cat DNAs, the U5 LTR segment from the Gardner-Arnstein strain B virus is present at approximately 150 copies per cell. This level is approximately 10-fold greater than that of endogenous internal FeLV sequences. The U5 sequences differ in copy number and, to some extent, in location from one animal to another. For any one animal, the sequence organization of the U5 segments is the same among different tissues, showing that the pattern is inherited through the germ line. Most importantly, the viral U3 LTR probe hybridizes only very weakly with uninfected cat DNAs. Both the U3 and the U5 regions of the LTR from the Gardner-Arnstein strain of virus cross-hybridize with DNA derived from four other infectious FeLVs representing A, B, and C subtypes. Thus, the U3 region may be used as a probe for studying the number and location of exogenously acquired FeLV proviruses in infected cat tissues. In some cases exogenously acquired proviruses are present in unique sites in the genome of virus-positive cat lymphosarcomas, indicating a monoclonal origin for the tumor. In other tumors, the proviral sequences are randomly distributed over many sites. Lymphosarcomas of virus-negative cats have no exogenous U3 sequences despite epidemiological evidence of an association of virus-negative leukemia with exposure to FeLV.

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Additional Information:Copyright © 1981 by the National Academy of Sciences. Contributed by Norman Davidson, July 20, 1981. This work was supported by Grants CA 26199 to M.O.N. and CA 25991 to N.D. from the National Institutes of Health. J.I.M. and K.B.B. were supported by fellowships from the National Institutes of Health, and A.R. by a Natural Sciences and Engineering Research Council of Canada Scholarship. The publication costs of this article were defrayed in part by page charge payment. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. §1734 solely to indicate this fact.
Subject Keywords:long terminal repeat; proviral integration; virus-negative leukemia; virus-positive leukemia; DNA-mediated transfection
Issue or Number:12
Record Number:CaltechAUTHORS:CASpnas81
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:10803
Deposited By: Archive Administrator
Deposited On:11 Jun 2008
Last Modified:03 Oct 2019 00:13

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