Eiden J J, Nataro J, Vonderfecht S, Petric M
Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205.
Virology. 1992 Jun;188(2):580-9. doi: 10.1016/0042-6822(92)90512-n.
The sixth genomic segment of the infectious diarrhea of infant rats (IDIR) strain of group B rotavirus (GBR) was cloned from double-stranded RNA purified from infected rat feces. Sequence comparison with group A rotaviruses (GAR) and the human ADRV strain of GBR indicated that IDIR gene 6 encoded the major inner capsid protein. The nucleic acid sequences of the two GBR genes were 72.9% conserved, and 83.4% of the amino acids were identical. Sequence substitutions between IDIR and ADRV were more numerous than reported for heterologous GAR strains, indicating that the two GBR strains may have diverged from one another over a longer period of time. Despite the sequence heterogeneity exhibited by the major inner capsid proteins of ADRV and IDIR, hydrophilicity plots of the two gene products were nearly indistinguishable. The GBR hydrophilicity plots displayed little similarity with those of rotavirus groups A or C, indicating substantial differences in the structures of those major inner capsid proteins. In vitro transcription and translation of IDIR gene 6 yielded a polypeptide product consistent in size with that predicted from the deduced amino acid sequence and the virion major inner capsid protein. The IDIR 6 polypeptide was immunoprecipitated by antisera directed against IDIR as well as antisera directed against ADRV and a heterologous bovine strain of GBR. No immunoprecipitation was observed with control sera or antisera directed against GAR. These results confirmed that group-specific epitopes were displayed by the major inner capsid protein encoded by IDIR gene 6. Reactivity with heterologous GBR antisera also indicated that the IDIR gene 6 product may prove useful as a standard reagent in immunoassays for the detection of GBR.
从感染大鼠粪便中纯化的双链RNA中克隆出B组轮状病毒（GBR）的婴儿大鼠感染性腹泻（IDIR）株的第六个基因组片段。与A组轮状病毒（GAR）和GBR的人ADRV株进行序列比较表明，IDIR基因6编码主要的内衣壳蛋白。两个GBR基因的核酸序列保守性为72.9%，氨基酸的一致性为83.4%。IDIR和ADRV之间的序列替换比报道的异源GAR株更多，表明这两个GBR株可能在更长的时间内彼此分化。尽管ADRV和IDIR的主要内衣壳蛋白表现出序列异质性，但这两种基因产物的亲水性图谱几乎无法区分。GBR亲水性图谱与A组或C组轮状病毒的图谱几乎没有相似性，表明这些主要内衣壳蛋白的结构存在实质性差异。IDIR基因6的体外转录和翻译产生了一种多肽产物，其大小与从推导的氨基酸序列和病毒粒子主要内衣壳蛋白预测的大小一致。IDIR 6多肽被针对IDIR的抗血清以及针对ADRV和GBR的异源牛株的抗血清免疫沉淀。用对照血清或针对GAR的抗血清未观察到免疫沉淀。这些结果证实，IDIR基因6编码的主要内衣壳蛋白展示了组特异性表位。与异源GBR抗血清的反应性还表明，IDIR基因6产物可能被证明是检测GBR的免疫测定中的一种有用的标准试剂。
