Characterization of the nucleoside triphosphate phosphohydrolase and helicase activities of the reovirus lambda 1 protein
Characterization of the nucleoside triphosphate phosphohydrolase and helicase activities of the reovirus lambda 1 protein
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DOI：
10.1074/jbc.272.29.18298
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发表时间：
1997-07-18
影响因子：
4.8
通讯作者：
Lemay, G
中科院分区：
文献类型：
--
作者：
Bisaillon, M;Bergeron, J;Lemay, G
先前的研究表明呼肠孤病毒lambda 1核心蛋白含有一个假定的核苷酸结合基序，并表现出对核酸的亲和力。此外，最近通过基因重组分析发现呼肠孤病毒核心中存在核苷三磷酸磷酸水解酶活性。在本研究中，我们证实了在酵母毕赤酵母中表达的重组lambda 1蛋白能够水解核苷5′-二磷酸或脱氧核苷5′-三磷酸。这种活性完全依赖于二价阳离子Mg2+或Mn2+的存在。该蛋白还可以在5'-三磷酸核苷或5'-三磷酸脱氧核苷存在的情况下展开双链核酸分子。这些结果提供了呼肠孤病毒lambda 1蛋白是一种核苷三磷酸磷酸水解酶/解旋酶的第一个生化证据，并有力地支持了lambda 1参与病毒基因组转录的观点。
Previous studies have shown that the reovirus lambda 1 core protein harbors a putative nucleotide-binding motif and exhibits an affinity for nucleic acids, In addition, a nucleoside triphosphate phosphohydrolase activity present in reovirus cores has been recently assigned to hi using gene reassortment analysis. In this study, it was demonstrated that the recombinant lambda 1 protein, expressed in the yeast Pichia pastoris, is able to hydrolyze nucleoside 5'-biphosphates or deoxynucleoside 5'-triphosphates. This activity was absolutely dependent on the presence of a divalent cation, Mg2+ or Mn2+. The protein can also unwind double-stranded nucleic acid molecules in the presence of a nucleoside 5'-triphosphate or deoxynucleoside 5'-triphosphate. These results provide the first biochemical evidence that the reovirus lambda 1 protein is a nucleoside triphosphate phosphohydrolase/helicase and strongly support the idea that lambda 1 participates in transcription of the viral genome.