Spiropoulou C F, Nichol S T
Cell and Molecular Biology Program, University of Nevada, Reno 89557.
J Virol. 1993 Jun;67(6):3103-10. doi: 10.1128/JVI.67.6.3103-3110.1993.
Vesicular stomatitis virus (VSV) has served for several decades as the prototype rhabdovirus and a model RNA virus. Extensive studies upheld the original view of VSV genetics with simply five genes (N, P, M, G, and L), each encoding a single unique protein. We now report the first unambiguous demonstration of the existence of an additional unique protein encoded in an overlapping frame within the virus P gene. Experiments using antipeptide sera specific for the predicted second open reading frame have demonstrated the synthesis of two N-terminally nested forms of the protein in virus-infected cells. The major form is 55 amino acids in length, whereas the minor form has 10 additional N-terminal amino acids. Ribosome initiation of synthesis of these proteins appears to occur at AUG codons, 68 and 41 bases, respectively, downstream of the P protein AUG initiation codon. The proteins are found in the cytoplasm of the infected cell but are undetectable in purified virions, consistent with their being nonstructural proteins. Both the major and minor forms of the protein are highly basic and arginine rich, reminiscent of the C and C' proteins encoded in overlapping frame close to the 5' terminus of the P mRNA of several paramyxoviruses. The potential to encode small, highly basic proteins within the P mRNA 5' terminus is highly conserved among the vesiculoviruses.
几十年来，水泡性口炎病毒（VSV）一直作为弹状病毒的原型和RNA病毒模型。广泛的研究支持了VSV遗传学的最初观点，即它只有五个基因（N、P、M、G和L），每个基因编码一种独特的蛋白质。我们现在首次明确证明，在病毒P基因内的一个重叠阅读框中存在另一种独特的蛋白质。使用针对预测的第二个开放阅读框的抗肽血清进行的实验表明，在病毒感染的细胞中合成了两种N端嵌套形式的蛋白质。主要形式长度为55个氨基酸，而次要形式在N端还有另外10个氨基酸。这些蛋白质的核糖体合成起始似乎分别发生在P蛋白AUG起始密码子下游68和41个碱基处的AUG密码子。这些蛋白质存在于受感染细胞的细胞质中，但在纯化的病毒粒子中无法检测到，这与它们是非结构蛋白一致。该蛋白质的主要和次要形式都具有高度碱性且富含精氨酸，这让人联想到几种副粘病毒P mRNA 5'末端附近重叠阅读框中编码的C和C'蛋白。在水泡病毒中，在P mRNA 5'末端编码小的、高度碱性蛋白质的潜力是高度保守的。
