Hammond J, Hammond R W
USDA-ARS, Florist and Nursery Crops Laboratory, Beltsville, Maryland 20705.
J Gen Virol. 1989 Aug;70 ( Pt 8):1961-74. doi: 10.1099/0022-1317-70-8-1961.
The sequence of 1015 nucleotides from the 3' poly(A) tract of the potyvirus bean yellow mosaic virus (BYMV) RNA has been determined from two cDNA clones. This sequence contained a single long open reading frame (ORF) starting upstream of the cloned region. The ORF was expressed as a fusion protein in Escherichia coli, and the product was detected by antibodies specific for the coat protein of BYMV. The predicted length of the coat protein gene was 822 nucleotides, corresponding to a 273 amino acid coat protein of Mr 30910. The deduced amino acid sequence of the BYMV coat protein was compared to the chemically determined amino acid composition of purified virion protein, and of protein prepared from trypsin-treated virions. The nucleotide and deduced amino acid sequences were compared to the sequences of the coat protein genes of other potyviruses. The BYMV coat protein gene was found to be 50 to 61% homologous to those of other potyviruses at both the nucleotide and amino acid levels; the greatest variation was between the 5'-proximal one-fifth of the genes. Amino acid sequences and hydrophilicity plots of the different potyvirus coat proteins showed similarities which indicated that the structure of the coat protein is highly conserved; a non-terminal region of variability was predicted to be exposed on the exterior of the virion. A putative cleavage site at a glutamine-serine dipeptide was identified by similarity in context to the cleavage sites of tobacco etch virus and tobacco vein mottling virus coat proteins from the viral polyproteins. The BYMV 3'-terminal non-coding region of 166 nucleotides is followed by a poly(A) tract.
从两个cDNA克隆中确定了马铃薯Y病毒属菜豆黄花叶病毒（BYMV）RNA 3'端多聚腺苷酸序列的1015个核苷酸。该序列包含一个单一的长开放阅读框（ORF），起始于克隆区域的上游。该ORF在大肠杆菌中表达为融合蛋白，其产物可通过对BYMV外壳蛋白特异的抗体进行检测。预测的外壳蛋白基因长度为822个核苷酸，对应于一个273个氨基酸、分子量为30910的外壳蛋白。将推导的BYMV外壳蛋白氨基酸序列与纯化病毒粒子蛋白以及胰蛋白酶处理的病毒粒子所制备蛋白的化学测定氨基酸组成进行了比较。将核苷酸和推导的氨基酸序列与其他马铃薯Y病毒属病毒的外壳蛋白基因序列进行了比较。发现BYMV外壳蛋白基因在核苷酸和氨基酸水平上与其他马铃薯Y病毒属病毒的基因同源性为50%至61%；最大的变异存在于基因5'端近端的五分之一区域。不同马铃薯Y病毒属病毒外壳蛋白的氨基酸序列和亲水性图谱显示出相似性，这表明外壳蛋白的结构高度保守；预测一个非末端可变区暴露于病毒粒子的外部。通过与烟草蚀纹病毒和烟草脉斑驳病毒外壳蛋白从病毒多聚蛋白中的切割位点在上下文上的相似性，鉴定出一个谷氨酰胺 - 丝氨酸二肽处的假定切割位点。BYMV 166个核苷酸的3'端非编码区之后是一个多聚腺苷酸序列。
