Nucleotide sequence diversity in RNA polymerase region of human calicivirus antigenically related to Sapporo 1982 strain.

基于对RNA依赖RNA聚合酶(RDRP)区基因组的分析，人类杯状病毒(HuCV)至少可分为三个基因组群：以诺沃克病毒(NV)为代表的基因组I，以雪山病毒(SMV)为代表的基因组II，以HuCV/Sapporo/82/J病毒为代表的基因组III。在三个基因群中，RDRP区的序列同源性不到70%，未发现抗原相关性。用RT-PCR方法扩增札幌市1979~1990年间儿童HUCV/Sa/82/J相关毒株的RDRP区，并进行序列测定。扩增产物的核苷酸和氨基酸序列与HuCV/Sa/82/J原型株的核苷酸和氨基酸序列高度一致，表明HuCV/Sa/82/J相关毒株RDRP区的抗原性与序列相似性之间存在相关性。这种病毒已经在札幌传播了至少10年。在美国、英国和沙特阿拉伯检测到的这些毒株在RDRP区也显示出与病毒原型的高度同源性。建立了一种用于检测HuCv/Sa/82/J及相关病毒的斑点杂交方法。NV全基因组和猫杯状病毒RNA在与HuCV/Sa/82/J cDNA的严格杂交条件下不发生杂交。斑点杂交法检测粪便标本中病毒的阳性率(21%)高于ELISA法(10%)。斑点杂交法具有特异性强、操作简便、试剂供应无限量等优点，可用于HuCV/Sa/82/J及相关毒株的流行病学和分子生物学研究。

Besed on genome analysis of the RNA dependent RNA polymerase (RDRP) region, it has been proposed that human calicivirus (HuCV) can be classified into at least three genogroups : genogroup I is represented by Norwalk virus (NV), genogroup II by Snow Mountain virus (SMV) and genogroup III by HuCV/Sapporo/82/Japan (HuCV/Sa/82/J) virus. Among three genogroups, the sequnece homology in RDRP region is less than 70% and antigenic relatedness has not been demonstrated. The RDRP region of HuCV/Sa/82/J-related strains collected from children in Sapporo between 1979 and 1990 was amplified by RT-PCR and sequenced. Nucleotide and amino acid sequences of the PCR products showed a high degree of identity among above samples and prototype of HuCV/Sa/82/J.These data indicate a correlation between the antigenicity and sequence similarity of the RDRP region among HuCV/Sa/82/J-related viruses. This virus has been circulating in Sapporo for at least 10 years. These strains detected in USA,UK and Saudi Arabia also showed a high degree of identity in the RDRP region to prototype of virus.A dot blot hybridization assay with a cDNA probe derived from the RDRP region of HuCV/Sa/82/J was developed for detection of HuCv/Sa/82/J.This assay was specific for HuCV/Sa/82/J and related viruses, and the sensitivity was about 10^5 physical particles or 10pg of cDNA.The entire genome of NV cDNA and feline calicivirus RNA did not hybridize under high stringent conditions of stringency with the HuCV/Sa/82/J cDNA.A higher positive rate for virus detection in stool samples was obtained with the dot blot assay (21%) than ELISA (10%). The dot blot assay is specific, easy to perform and advantageous with unlimited supply of reagents, and should be useful for epidemiological and molecular biological studies of HuCV/Sa/82/J and related strains.