title: Identification of two novel multiple recombinant avian leukosis viruses in two different lines of layer chicken.
abstract: Avian leukosis virus (ALV) is the most common oncogenetic retrovirus that emerges spontaneously as a result of recombination between exogenous viruses, exogenous viruses and endogenous viruses, and exogenous viruses and non-homologous cellular genes. In the present study, two natural recombinant avian leukosis viruses (rALVs) (LC110515-5 and LC110803-5) carrying a subgroup C gp85 gene, a subgroup E gp37 gene, and a subgroup J 3'UTR and 3'LTR were isolated from two different lines of layer flocks, Black-bone silky fowl (BSF) and commercial layer chicken, that suffered from myeloid leukosis. Although tumours were not observed in rALV-infected individual chickens, other non-neoplastic inflammatory lesions were evident. The two rALVs were cultured on DF-1 cells and identified by PCR, immunofluorescence assay and gene sequencing. The gp85 nucleotide sequence in the two isolates displayed a high identity (>95 %) with that of the gp85 gene in ALV-C, but the identity was less than 90 % with ALV-A/B/D/E and only 51 % with ALV-J. Phylogenetic analysis of the nucleotide and amino acid sequences confirmed that the two isolates were recombinant between ALV-C, ALV-E and ALV-J. Subgroup C ALV is rarely found in field cases. This report is the first to provide evidence that ALV-C has recombined with ALV-E and ALV-J in two different chicken lines. The source and characteristics of the two rALVs and ALV-C need to be further investigated.
authors.affiliation: College of Veterinary Medicine, Shandong Agricultural University, Tai'an 271018, China.
authors.forename: Liming
authors.initials: L
authors.lastname: Cai
authors.affiliation: College of Veterinary Medicine, Shandong Agricultural University, Tai'an 271018, China.
authors.forename: Yanwei
authors.initials: Y
authors.lastname: Shen
authors.affiliation: College of Veterinary Medicine, Shandong Agricultural University, Tai'an 271018, China.
authors.forename: Guihua
authors.initials: G
authors.lastname: Wang
authors.affiliation: Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Agricultural University, Tai'an 271018, China.|College of Veterinary Medicine, Shandong Agricultural University, Tai'an 271018, China.
authors.forename: Huijun
authors.initials: H
authors.lastname: Guo
authors.affiliation: Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Agricultural University, Tai'an 271018, China.|College of Veterinary Medicine, Shandong Agricultural University, Tai'an 271018, China.
authors.forename: Jianzhu
authors.initials: J
authors.lastname: Liu
authors.affiliation: Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Agricultural University, Tai'an 271018, China.|College of Veterinary Medicine, Shandong Agricultural University, Tai'an 271018, China.
authors.forename: Ziqiang
authors.initials: Z
authors.lastname: Cheng
mesh_terms: D020413:3' Untranslated Regions / Q000235:genetics; D000595:Amino Acid Sequence; D000818:Animals; D001353:Avian Leukosis / Q000473:pathology / Q000821:virology*; D001354:Avian Leukosis Virus / Q000145:classification / Q000235:genetics*; D001483:Base Sequence; D002645:Chickens / Q000145:classification / Q000235:genetics*; D005260:Female; D008969:Molecular Sequence Data; D010058:Oviposition; D010802:Phylogeny; D012367:RNA, Viral / Q000235:genetics; D016865:Reassortant Viruses / Q000145:classification / Q000235:genetics*; D016415:Sequence Alignment / Q000662:veterinary; D014759:Viral Envelope Proteins / Q000737:chemistry / Q000235:genetics
chemical_list: D020413:3' Untranslated Regions; D012367:RNA, Viral; C062390:Rous sarcoma virus envelope protein gp37; D014759:Viral Envelope Proteins