Wengler G, Castle E, Leidner U, Nowak T, Wengler G
Virology. 1985 Dec;147(2):264-74. doi: 10.1016/0042-6822(85)90129-1.
Flaviviruses contain a large membrane-associated protein V3, having a mol mass of about 50 kDa which is responsible for hemagglutination. We have isolated the V3 protein from the West Nile (WN) flavivirus and determined its amino-terminal amino acid sequence and amino acid sequences of fragments derived from this protein. We have also transcribed parts of the WN virus genome RNA into cDNA and cloned and sequenced this cDNA. The results of these analyses have allowed us to identify the region of the viral genome coding for the V3 protein. In this report we describe the total nucleotide sequence of the genome region coding for the WN virus V3 protein and the amino acid sequence of the V3 protein derived from these analyses. The exact carboxy terminus of the V3 protein has not been determined in these experiments. These analyses have shown that the V3 protein of WN virus does not contain an Asn-X-Ser/Thr sequence which could allow addition of N-linked carbohydrate chains to this protein. In accordance with this finding, analyses of metabolic labeling of the V3 protein using [3H]glucosamine indicate that the WN virus V3 protein is an unglycosylated protein. Together with our earlier analyses these results show that the viral structural proteins are present on the genome RNA in the order 5'-terminus-core protein (V2)-small membrane-associated protein (NV2)-large membrane-associated protein (V3) and describe the nucleotide sequences coding for all WN virus structural proteins identified so far. A hypothesis concerning the processes involved in the synthesis of all viral structural proteins and the probable orientation of these proteins relative to the endoplasmatic reticulum membrane based on the structure of these proteins is discussed.
黄病毒含有一种与膜相关的大分子蛋白V3，其分子量约为50 kDa，负责血凝作用。我们已从西尼罗河（WN）黄病毒中分离出V3蛋白，并确定了其氨基末端氨基酸序列以及该蛋白衍生片段的氨基酸序列。我们还将WN病毒基因组RNA的部分转录成cDNA，并对该cDNA进行了克隆和测序。这些分析结果使我们能够鉴定出病毒基因组中编码V3蛋白的区域。在本报告中，我们描述了编码WN病毒V3蛋白的基因组区域的总核苷酸序列以及通过这些分析得出的V3蛋白的氨基酸序列。在这些实验中尚未确定V3蛋白的确切羧基末端。这些分析表明，WN病毒的V3蛋白不包含可允许向该蛋白添加N-连接糖链的Asn-X-Ser/Thr序列。根据这一发现，使用[3H]葡糖胺对V3蛋白进行代谢标记的分析表明，WN病毒V3蛋白是一种未糖基化的蛋白。与我们早期的分析一起，这些结果表明病毒结构蛋白在基因组RNA上的排列顺序为5'-末端-核心蛋白（V2）-小膜相关蛋白（NV2）-大膜相关蛋白（V3），并描述了迄今为止鉴定出的所有WN病毒结构蛋白的编码核苷酸序列。基于这些蛋白的结构，讨论了关于所有病毒结构蛋白合成过程以及这些蛋白相对于内质网膜可能取向的假说。
