RESUMEN
The J-subgroup avian leukosis virus (ALV-J) strain WB11098J was isolated from a wild Eurasian teal, and its proviral genomic sequences were determined. The complete proviral sequence of WB11098J was 7868 nt long. WB11098J was 95.3.9 % identical to the prototype strain HPRS-103, 94.2 % identical to the American strain ADOL-7501, 94.5-94.7 % identical to Chinese broiler isolates, 94.8-97.5 % identical to layer chicken isolates, and 94.4-95.0 % identical to Chinese local chicken isolates at the nucleotide level. Phylogenetic analysis showed that the WB11098J isolate shared the greatest homology with the layer strain SD09DP03 and was included in the same cluster. Interestingly, two 19-bp insertions in the U3 regions of the 5'LTR and 5'UTR that were most likely derived from other retroviruses were found in the WB11098J isolate. These insertions separately introduced one E2BP-binding site in the U3 region of the 5'LTR and a RNA polymerase II transcription factor IIB and core promoter motif of ten elements in the 5'UTR. A 5-bp deletion was identified in the U3 region of the 5'LTR. No nucleotides were deleted in the rTM or DR-1 regions in the 3'UTR. A 1-bp deletion was detected in the E element and introduced a specific and distinct binding site for c-Ets-1. Our study is the first to report the molecular characteristics of the complete genome of an ALV-J that was isolated from a wild bird and will provide necessary information for further understanding of the evolution of ALV-J.
Asunto(s)
Anseriformes/virología , Virus de la Leucosis Aviar/clasificación , Virus de la Leucosis Aviar/aislamiento & purificación , ADN Viral/genética , Genoma Viral , Análisis de Secuencia de ADN , Animales , Virus de la Leucosis Aviar/genética , China , Análisis por Conglomerados , ADN Viral/química , Genotipo , Datos de Secuencia Molecular , Filogenia , Provirus/clasificación , Provirus/genética , Provirus/aislamiento & purificación , Homología de SecuenciaRESUMEN
To analyze the status of wild birds infected with avian leukosis virus (ALV) in China, we collected 300 wild birds from various areas. Virus isolation and PCR showed that wild birds were infected by ALV-A and ALV-B. Two ALV-A and 4 ALV-B env sequences were obtained by PCR using primers designed to detect ALV-A and -B respectively. Our results showed that the gp85 genes of the 2 ALV-A strains have the highest homology with RAV-1, 99.8%, and more than 92% homology with other American strains. However, the gp85 genes of the two ALV-A strains showed slightly lower homology with Chinese strains (87.2-92.6%). Additionally, the 4 ALV-B strains have high homology with the prototype strain (RAV-2), from 99.1 to 99.4%, but they have slightly lower identity with Schmidt-Ruppin B and Prague subgroup B, from 93.3 to 98.4%. The 4 ALV-B strains showed the lowest identity with SDAU09C2 and SDAU09E3 (90%). In total, these results suggested that avian leukosis virus has infected wild birds in China.