Submitted to: Journal of Virology
Publication Type: Peer reviewed journal
Publication Acceptance Date: 9/11/1998
Publication Date: N/A
Citation: Interpretive Summary: Subgroup J avian leukosis virus (ALV-J) is an emerging economically important virus infection that can cause cancer-like disease and other production problems in meat-type chickens. Understanding the molecular structure of ALV-J is an important component of any effort to develop specific diagnostics and effective control programs. Molecular characterization of ALV-J revealed that the sequence of DNA units (genetic code) of the envelope gene of ALV-J is over 95% identical to a novel family of endogenous host-related genetic elements (DNA) termed endogenous viruses. Our data support the hypothesis that ALV-J was acquired by recombination of these endogenous host-related and exogenous viral genetic elements. This new information is significant and should be useful to other scientists who are studying the basic principals of mutation and transmission of this emerging virus infection of meat-type chickens.
Technical Abstract: A new subgroup of avian leukosis virus (ALV), designated subgroup J, was identified recently. Viruses of this subgroup do not cross-interfere with viruses of the avian A, B, C, D, and E subgroups, are not neutralized by antisera raised against the other virus subgroup, and have a broader host range than the A to E subgroups. Sequence comparisons reveal that while the subgroup J envelope gene includes some regions that are related to those found in env genes of the A to E subgroups, the majority of the subgroup J gene is composed of sequences either that are more similar to those of a member (E51) of the ancient endogenous avian virus (EAV) family of proviruses or that appear unique to subgroup J viruses. These data led to the suggestion that the ALV-J env gene might have arisen by multiple recombination events between one or more endogenous and exogenous viruses. We initiated studies to investigate the origin of the subgroup J envelope gene and in particular to determine the identity of endogenous sequences that may have contributed to its generation. Here we report the identification of a novel family of avian endogenous viruses that include env coding sequences that are over 95% identical to both the gp85 and gp37 coding regions of subgroup J viruses. We call these viruses the ev/J family. We also report the isolation of ev/J encoded cDNAs, indicating that at least some members of this family are expressed.