Zeng Wei, Zeng Yong, Fei Rong-Mei, Zeng Ling-Bing, Wei Kai-Jin
College of Chemistry and Biology, Yantai University, Shandong 264005, PR China.
Dis Aquat Organ. 2011 Sep 9;96(2):105-12. doi: 10.3354/dao02388.
Variable genomic loci were examined in 4 white spot syndrome virus (WSSV) isolates (08HB, 09HB, 08JS and 09JS) from Procambarus clarkii crayfish collected from Jiangsu and Hubei Provinces in China in 2008 and 2009. In ORF75, sequence variation detected in the 4 isolates, as well as in isolates sequenced previously, suggested that WSSV might have segregated into 2 lineages since first emerging as a serious pathogen of farmed shrimp in East Asia in the early-mid 1990s, with one lineage remaining in East Asia and the other separating to South Asia. In ORF23/24, deletions of 9.31, 10.97, or 11.09 kb were evident compared to a reference isolate from Taiwan (WSSV-TW), and, in ORF14/15, deletions of 5.14 or 5.95 kb were evident compared to a reference isolate from Thailand with the largest genome size (TH-96-II). With respect to these genome characteristics, the crayfish isolates 08HB, 09HB and 08JS were similar to WSSV-TW and the isolate 09JS was similar to a reference isolate from China (WSSV-CN). In addition to these loci, sequence variation was evident in ORF94 and ORF125 that might be useful for differentiating isolates and in epidemiological tracing of WSSV spread in crayfish farmed in China. However, as all 4 crayfish isolates possessed a Homologous Region 9 sequence identical to isolate WSSV-TW and another Thailand isolate (WSSV-TH), and as their transposase sequence was identical to isolates WSSV-CN and WSSV-TH, these 2 loci were not useful in predicting their origins.
对2008年和2009年从中国江苏省和湖北省采集的克氏原螯虾中分离得到的4株白斑综合征病毒（WSSV）（08HB、09HB、08JS和09JS）的可变基因组位点进行了检测。在ORF75中，这4株分离株以及先前测序的分离株中检测到的序列变异表明，自20世纪90年代中后期首次成为东亚养殖虾的严重病原体以来，WSSV可能已分为2个谱系，一个谱系留在东亚，另一个谱系则扩散到南亚。在ORF23/24中，与来自台湾的参考分离株（WSSV-TW）相比，明显缺失了9.31、10.97或11.09 kb；在ORF14/15中，与基因组最大的来自泰国的参考分离株（TH-96-II）相比，明显缺失了5.14或5.95 kb。就这些基因组特征而言，螯虾分离株08HB、09HB和08JS与WSSV-TW相似，分离株09JS与来自中国的参考分离株（WSSV-CN）相似。除了这些位点外，ORF94和ORF125中也存在明显的序列变异，这可能有助于区分分离株以及对中国养殖螯虾中WSSV传播进行流行病学追踪。然而，由于所有4株螯虾分离株的同源区域9序列与分离株WSSV-TW和另一株泰国分离株（WSSV-TH）相同，且它们的转座酶序列与分离株WSSV-CN和WSSV-TH相同，因此这2个位点无法用于预测它们的来源。
