Johansen E, Rasmussen O F, Heide M, Borkhardt B
Danish Research Service for Plant and Soil Science, Lyngby.
J Gen Virol. 1991 Nov;72 ( Pt 11):2625-32. doi: 10.1099/0022-1317-72-11-2625.
The complete nucleotide sequence of the RNA genome of pea seed-borne mosaic virus (PSbMV) was determined from cloned cDNA and by direct sequencing of viral RNA. The PSbMV genomic sequence was determined to be 9924 nucleotides in length excluding the poly(A) tract. The RNA contained an open reading frame (ORF) of 9618 nucleotides with the potential to encode a polyprotein with a calculated Mr of 364000 (364K). The ORF was flanked by a 5' untranslated leader sequence of 143 nucleotides and a 3' untranslated region of 163 nucleotides. A comparison of the PSbMV polyprotein with the polyproteins of the potyviruses tobacco etch virus (TEV), tobacco vein mottling virus (TVMV), plum pox virus (PPV) and potato virus Y (PVY) showed that PSbMV had a similar genome organization. The polyproteins had a high level of amino acid identity except in the N-terminal region, which varied in both sequence and length. Putative proteolytic cleavage sites were identified in the polyprotein of PSbMV by comparison with those identified for other potyviruses. The cleavage site between the 6K protein and the 49K proteinase is proposed to occur at the C-terminal side of glutamic acid and not at the C-terminal side of glutamine as in other potyviruses. In addition to the five proteolytic cleavage sites for the 49K proteinase identified previously, a sixth putative cleavage site was identified internally in the 49K proteinase of PSbMV, as well as in the 49K proteinases of TEV, TVMV, PPV, PVY and soybean mosaic virus. Cleavage at this site in the 49K proteinases of TEV, TVMV and PPV would result in an N-terminal protein of 22K to 24K, which is similar in size to the size determined for their VPgs.
通过对克隆的 cDNA 以及病毒 RNA 的直接测序，确定了豌豆种传花叶病毒（PSbMV）RNA 基因组的完整核苷酸序列。PSbMV 基因组序列长度为 9924 个核苷酸，不包括 poly(A) 尾。该 RNA 包含一个 9618 个核苷酸的开放阅读框（ORF），有可能编码一个计算分子量为 364000（364K）的多聚蛋白。该 ORF 两侧分别是一个 143 个核苷酸的 5' 非翻译前导序列和一个 163 个核苷酸的 3' 非翻译区。将 PSbMV 多聚蛋白与马铃薯 Y 病毒属的烟草蚀纹病毒（TEV）、烟草脉斑驳病毒（TVMV）、李痘病毒（PPV）和马铃薯 Y 病毒（PVY）的多聚蛋白进行比较，结果表明 PSbMV 具有相似的基因组结构。这些多聚蛋白除了在 N 端区域外，氨基酸同源性水平较高，N 端区域在序列和长度上均有所不同。通过与其他马铃薯 Y 病毒属病毒确定的蛋白水解切割位点进行比较，在 PSbMV 的多聚蛋白中鉴定出了推定的蛋白水解切割位点。6K 蛋白和 49K 蛋白酶之间的切割位点被认为发生在谷氨酸的 C 端一侧，而不像其他马铃薯 Y 病毒属病毒那样发生在谷氨酰胺的 C 端一侧。除了先前确定的 49K 蛋白酶的五个蛋白水解切割位点外，在 PSbMV 的 49K 蛋白酶内部以及 TEV、TVMV、PPV、PVY 和大豆花叶病毒的 49K 蛋白酶中还鉴定出了第六个推定的切割位点。TEV、TVMV 和 PPV 的 49K 蛋白酶在此位点切割会产生一个 22K 至 24K 的 N 端蛋白，其大小与它们的 VPg 大小相似。
