Lack of infectivity of the endogenous avian leukosis virus-related genes in the DNA of uninfected chicken cells.
The infectivity of the avian leukosis virus-related genes in the DNA of four genetically distinct types of chicken cells was determined. Infectious DNA of Rous-associated virus-O(RAV-O) was obtained from V- chicken cells which were experimentally infected with RAV-O and from V+tvbs chicken cells, which spontaneously produced RAV-O and were sensitive to exogenous RAV-O infection. However, infectious DNA of RAV-O was not obtained from uninfected V- chicken cells or from V+tvbr chicken cells, which spontaneously produced a low titer of RAV-O but were resistant to exogenous RAV-O infection. No detectable amplification of the RAV-O related DNA sequences in the V+tvbs cells was found by hybridization of RAV-O 125I-labeled RNA to the DNAs of V+tvbs and uninfected V- cells. These results indicate that the endogenous avian leukosis virus-related genes in uninfected V- and V+tvbr cells differ from the RAV-O proviruses in RAV-O-infected V- and V+tvbs cells. The lack of infectivity of the DNA of V+tvbr cells is consistent with the hypothesis that the endogenous RAV-O genome in V+tvbr cells is linked to a cis-acting control element, which results in its inefficient expression.
D000818:Animals; D001354:Avian Leukosis Virus / Q000032:analysis / Q000201:enzymology / Q000254:growth & development*; D001483:Base Sequence; D002460:Cell Line; D002474:Cell-Free System; D002642:Chick Embryo; D004247:DNA / Q000032:analysis*; D004254:DNA Nucleotidyltransferases / Q000378:metabolism; D005347:Fibroblasts / Q000032:analysis*; D014779:Virus Replication
D004247:DNA; D004254:DNA Nucleotidyltransferases