Sequence of host-range determinants in the env gene of a full-length, infectious proviral clone of exogenous avian leukosis virus HPRS-103 confirms that it represents a new subgroup (designated J).
A genomic DNA library was constructed, in a bacteriophage lambda vector, from line 0 chick embryo fibroblasts (CEFs) infected with HPRS-103, an exogenous avian leukosis virus (ALV; envelope subgroup J) recently isolated from meat-type chickens. The library was screened at high stringency using a full length RAV-1 (subgroup A) proviral probe. From 10(6) plaques, two clones which hybridized strongly to the RAV-1 probe were isolated; one contained a full-length copy of the proviral genome of HPRS-103 and the other contained a copy lacking the 5'-long terminal repeat (LTR) and part of gag. The relative strength of hybridization of RAV-1 and HPRS-103 clones, to RAV-1 probes representing different parts of the proviral genome, indicated that the gag and pol genes of HPRS-103 share a high level of identity with those of RAV-1 but that the env gene and the LTRs are considerably less well conserved. Infectious virus was recovered from CEFs transfected with the full-length clone, as detected by ELISA. The recovered virus appeared to be identical to HPRS-103 by electron microscopy and by Southern blotting of proviral DNA. The recovered virus was shown to be of the same subgroup as HPRS-103 by serum neutralization and receptor interference assays. Sequence analysis of the env gene of HPRS-103 shows that it differs considerably from the env genes of other ALV subgroups, particularly in the host range determinants, consistent with the finding that HPRS-103 represents a new subgroup (designated J).
Department of Molecular Biology, Institute for Animal Health, Compton, Nr Newbury, Berks, UK.
J
J
Bai
K
K
Howes
L N
LN
Payne
M A
MA
Skinner
D000595:Amino Acid Sequence; D000818:Animals; D001354:Avian Leukosis Virus / Q000145:classification / Q000235:genetics*; D002642:Chick Embryo; D015752:Genes, env; D008969:Molecular Sequence Data; D011533:Proviruses / Q000235:genetics*; D012091:Repetitive Sequences, Nucleic Acid; D014759:Viral Envelope Proteins / Q000737:chemistry
D014759:Viral Envelope Proteins