Zhang X M, Kousoulas K G, Storz J
Department of Veterinary Microbiology and Parasitology, School of Veterinary Medicine, Louisiana State University, Baton Rouge 70803.
Virology. 1992 Jan;186(1):318-23. doi: 10.1016/0042-6822(92)90089-8.
The complete nucleotide sequences of the hemagglutinin/esterase (HE) genes of human coronavirus (HCV) strain OC43 and bovine respiratory coronavirus (BRCV) strain G95 were determined from single-stranded cDNA fragments generated by reverse transcription of virus-specific mRNAs and amplified by polymerase chain reaction. An open reading frame of 1272 nucleotides was identified as the putative HE gene by homology to the bovine coronavirus HE gene. This open reading frame encodes a protein of 424 amino acids with an estimated molecular weight of 47.7 kDa. Ten potential N-linked glycosylation sites were predicted in the HE protein of HCV-OC43 while nine of them were present in BRCV-G95. Fourteen cysteine residues were conserved in the HE proteins of both viruses. Two hydrophobic sequences at the N-terminus and the C-terminus may serve as signal peptide and transmembrane anchoring domain, respectively. The predicted HE protein of HCV-OC43 was 95% identical to the HEs of BRCV-G95 and other bovine coronaviruses, and 60% identical to the HEs of mouse hepatitis viruses. Phylogenetic analysis suggests that the HE genes of coronaviruses and influenza C virus have a common ancestral origin, and that bovine coronaviruses and HCV-OC43 are closely related.
通过对病毒特异性mRNA进行逆转录生成单链cDNA片段，并经聚合酶链反应扩增，测定了人冠状病毒（HCV）OC43株和牛呼吸道冠状病毒（BRCV）G95株血凝素/酯酶（HE）基因的完整核苷酸序列。通过与牛冠状病毒HE基因的同源性，将一个1272个核苷酸的开放阅读框鉴定为推定的HE基因。该开放阅读框编码一个424个氨基酸的蛋白质，估计分子量为47.7 kDa。在HCV-OC43的HE蛋白中预测有10个潜在的N-连接糖基化位点，而在BRCV-G95中有9个。两种病毒的HE蛋白中有14个半胱氨酸残基保守。N端和C端的两个疏水序列可能分别作为信号肽和跨膜锚定结构域。预测的HCV-OC43的HE蛋白与BRCV-G95和其他牛冠状病毒的HE蛋白有95%的同一性，与小鼠肝炎病毒的HE蛋白有60%的同一性。系统发育分析表明，冠状病毒和丙型流感病毒的HE基因有共同的祖先起源，并且牛冠状病毒和HCV-OC43密切相关。
