Avian leukosis virusAvian LeukosisAlpharetrovirusChickensAvian Sarcoma VirusesBursa of FabriciusAvian ProteinsChick EmbryoGlycoproteinsReceptors, VirusPoultry DiseasesReticuloendotheliosis virusSarcoma, AvianQuailGenes, polCoturnixDNA, ViralGenes, envProvirusesMolecular Sequence DataVirus ReplicationGenes, gagAvian myeloblastosis virusHerpesvirus 2, GallidHemangiomaDefective VirusesCell LineRNA, ViralGenes, ViralMarek DiseaseLymphomaRepetitive Sequences, Nucleic AcidEndogenous RetrovirusesRNA-Directed DNA PolymeraseViral Envelope ProteinsViral InterferenceBase SequenceCulture TechniquesTenosynovitisEnzootic Bovine LeukosisRecombination, GeneticRetroviridaeVirus IntegrationCytopathogenic Effect, ViralOncogenesAmino Acid SequenceAntigens, ViralBirdsRetroviridae ProteinsCell Transformation, ViralViral ProteinsFibroblastsGenetic VectorsCell Transformation, NeoplasticNucleic Acid HybridizationSpecies SpecificityRNA VirusesCells, CulturedHelper VirusesVaccinia virusSequence Analysis, DNACloning, MolecularGenome, ViralGene Products, envVirus CultivationViral Fusion ProteinsSequence Homology, Nucleic AcidVirionDNA PrimersHistiocytic SarcomaMembrane Glycoproteins