The envelope gene of ADOL-4817 strain of avian leukosis viru s subgroup J (ALV-J) was amplified by polymerase chain reaction （PCR） and clo ned into TA vector. The sequence analysis results showed that the envelope gene is composed of 1?746 bp, 1?554 bp of which could be translated into 517 amino acids for gp85 and gp37. The molecular weight of envelope protein is 57.7kD. T here are 15 potential glycosylation sites in the envelope protein, 13 of which i s located in gp85. Analysis of sequences of envelope gene indicate that ADOL -4817 showed high degree of sequence identity to other ALV-J strains, and m ost close ly related to the like-envelope gene of endogenous virus EAV-HP but divergent from these of other ALV subgroup A-E . These data support the hypothesis that envelope gene of avian leukosis virus subgroup J maybe acquired by recombination with expressed sequences.

Two subgroup J avian leukosis viurses (ALVs) were isolated from broiler breeder flocks, in which myeloid leukosis had occurred. The isolates could be classified as subgroup J ALV. by the positive reaction in polymerase chain reaction (PCR) with primers specific for subgroup J ALV. Two isolates replicated in chicken embryo fibroblast (CEF) cells from the alv6 chicken line in which cells are resistant to subgroup A and E ALVs. In in vitro serum neutralization tests with other subgroup ALVs including ADOL-Hc1, the prototype of subgroup J ALVs isolated in the United States of America, two isolates were partially neutralized by antibody to ADOL-Hc1, indicating that Korean isolates and ADOL-Hc1 may be antigenically related, but not identical. When the PCR was done with a primer pair designed to amplify genes of E element and long terminal repeat of proviral DNA, the PCR product size of one isolate (KOAL-PET) was smaller than that of ADOL-Hc1, suggesting that some sequences in these regions are deleted.
Animals ; Antibodies, Viral/immunology ; Antigens, Viral/immunology ; Avian Leukosis/virology ; Avian leukosis virus/*classification/genetics/immunology/*isolation & purification ; Cell Line ; Chick Embryo ; Chickens/*virology ; Korea ; Neutralization Tests ; Polymerase Chain Reaction ; Poultry Diseases/virology