摘要
为研究目前中国临床流行的ALV毒株特征,我们采集临床上ALV P27阳性的鸡的血浆,接种DF-1细胞进行病毒分离,分离出6株外源性ALV毒株,并进一步对分离毒株进行前病毒全基因组测序。结果表明,6个ALV分离株的基因组结构均为典型的复制完整型C型逆转录病毒,缺乏病毒致癌基因,分离株DT190901基因组全长为7473 bp;DT190902和DT190905为7467 bp;DT190903和DT190906为7481 bp;DT190904为7493 bp,分离株间基因组序列同源性较高(98.6%~99.9%)。对6个ALV分离株与其他ALV毒株进行序列比较和遗传进化分析,结果表明,分离株的LTR、gag、pol及gp37基因与内源性ALV相比具有较高同源性(>93.8%),gp85基因与ALV-K一致性较高(>95.4%),属于新型ALV亚群(K亚群)遗传分支。分离株的LTR序列与内源性ALV相似,比其他外源性ALV亚群缺少一个CAAT Box、PRE Box、Y Box及CArG Box等转录调控元件。结果表明这6个分离株属于ALV-K亚群,为ALV-K与内源性ALV的重组毒株,其LTR序列与内源性ALV接近可能导致其复制能力及致病性降低。遗传进化分析表明,ALV-K已经在我国局部流行,并出现基因重组和突变毒株,应该引起重视并改进净化防控措施控制ALV-K流行。
To study the characteristics of the currently prevalent ALV strains in China,we collected plasma samples from ALV P27 antigen-positive chickens for inoculation into DF-1 cells and isolated 6 exogenous ALV strains.Further sequencing of the proviral genome of the isolated strains showed that the genome structures of these 6 ALV isolates were all typical replication-competent type C retroviruses lacking viral oncogene.The complete proviral genome sequences of these ALV isolates were 7482 bp for DT1909017467 bp for DT190902 and DT190905,7481 bp for DT190903 and DT190906,and 7493 bp for DT190904.The genome sequences of these isolates were highly identical,ranging from 98.6%to 99.9%.Homology analysis indicated that theirLTR,gag,polandgp37genes were highly conserved to endogenous ALV(>93.8%),whereas the gp85 gene had high identity to ALV-K(>95.4%).The LTR sequence of these isolates was similar to the endogenous ALV,and lacked a CAAT Box,PRE Box,Y Box,and CArG Box transcriptional regulatory elements as compared with other ALV subgroups.These results indicated that these 6 isolates belonged to the novel subgroup ALV-K and probably emerged by recombination of ALV-K with endogenous viruses.Their LTR sequence was similar to that of endogenous ALV,which might lead to the low replication and pathogenicity.Phylogenetic analysis suggested that ALV-K was common in Chinese local breed chickens with genomic recombination and mutation.Much attention should be paid to this situation for improving the prevention and control measures for ALV-K infection.
作者
游广炬
阿热阿依·海依拉提
李炜
李晓齐
高丽
曹红
王永强
郑世军
YOU Guangju;ARAY·Hayrat;LI Wei;LI Xiaoqi;GAO Li;CAO Hong;WANG Yongqiang;ZHENG Shijun(National Key Laboratory of Public Health and Safety,College of Veterinary Medicine,China Agricultural University,Beijing 100193,China)
出处
《中国动物传染病学报》
CAS
北大核心
2023年第6期116-126,共11页
Chinese Journal of Animal Infectious Diseases
基金
行业专项及国家蛋鸡产业技术体系项目(CARS-40)。
