PUTATIVE-65 KDA PROTEIN OF BEET YELLOWS CLOSTEROVIRUS IS A HOMOLOG OF HSP70 HEAT-SHOCK PROTEINS
PUTATIVE-65 KDA PROTEIN OF BEET YELLOWS CLOSTEROVIRUS IS A HOMOLOG OF HSP70 HEAT-SHOCK PROTEINS
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DOI：
10.1016/0022-2836(91)90517-a
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发表时间：
1991-02-20
影响因子：
5.6
通讯作者：
DOLJA, VV
中科院分区：
文献类型：
--
作者：
AGRANOVSKY, AA;BOYKO, VP;DOLJA, VV
甜菜黄化梭状病毒（BYV）的RNA基因组的一部分已经被测序，其包含可能编码65 kDa蛋白的完整长开放阅读框（ORF）。这种推定蛋白质的序列与HSP 70相关热休克蛋白的序列惊人相似。在HSP 70中高度保守的所有8个片段的对应物可以在BYV 65 kDa蛋白中确信地鉴定。这表明这些片段中的一些可能是ATP结合位点，并且与热休克蛋白类似，65 kDa可能是ATP结合位点。然而，一般来说，65 kDa序列和HSP 70序列之间的分歧比后一个家族的任何两个成员之间的分歧要明显得多，从而可以更清楚地描绘可能对蛋白质功能至关重要的保守残基簇。这表明，这些观察将有助于在HSP 70家族的蛋白质的功能解剖。对65 kDa ORF上游部分ORF序列的分析表明，编码蛋白的C-末端结构域可能是一种依赖RNA的RNA聚合酶，与三角RNA病毒（一种具有三个组分基因组的RNA植物病毒家族）的RNA聚合酶密切相关。
A portion of the RNA genome of beet yellows closterovirus (BYV) has been sequenced encompassing a complete long open reading frame (ORF) potentially encoding a 65 kDa protein. The sequence of this putative protein was strikingly similar to those of HSP70-related heat shock proteins. The counterparts of all the eight segments strongly conserved in HSP70s could be confidently identified in the BYV 65 kDa protein. It is suggested that some of these segments might be the ATP-binding site(s) and that, similarly to the heat shock proteins, the 65 kDa is probably ATP-binding. Generally, however, the divergence between the 65 kDa sequence and the sequences of the HSP70s was much more pronounced than that between any two members of the latter family, allowing a clearer delineation of clusters of conserved residues that might be crucial for protein function. It is suggested that these observations will be helpful in functional dissection of the proteins of the HSP70 family. Analysis of the sequence of a portion of the ORF found upstream from the 65 kDa ORF showed that the C-terminal domain of the encoded protein could be an RNA-dependent RNA polymerase closely related to those of tricornaviruses, a family of RNA plant viruses with three component genomes.