AKR murine leukemia virusLeukemia Virus, MurineMice, Inbred AKRMoloney murine leukemia virusMice, Inbred StrainsLeukemia, ExperimentalFriend murine leukemia virusReceptors, VirusRetroviridae InfectionsAbelson murine leukemia virusGenes, ViralDNA, ViralLeukemia Virus, FelineProvirusesRauscher VirusCell LineRetroviridaeViral Envelope ProteinsLeukemia Virus, BovineVirus ReplicationBase SequenceRetroviridae Proteins, Oncogenic3T3 CellsMolecular Sequence DataLeukemiaMink Cell Focus-Inducing VirusesLymphomaThymus NeoplasmsRecombination, GeneticMinkRNA-Directed DNA PolymeraseAmino Acid SequenceDNA Restriction EnzymesNucleic Acid HybridizationTumor Virus InfectionsGammaretrovirusGene Products, gagSpecies SpecificityMembrane FusionCloning, MolecularLeukemia, Myeloid, AcuteVirus IntegrationRNA, ViralLeukemia Virus, Gibbon ApeViral ProteinsDefective VirusesPreleukemia