An endonuclease isolated from Epstein-Barr virus-producing human lymphoblastoid cells.
An endonuclease isolated from Epstein-Barr virus-producing human lymphoblastoid cells.
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一种从产生 Epstein-Barr 病毒的人淋巴母细胞中分离出来的核酸内切酶。
DOI：
10.1073/pnas.77.10.6194
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发表时间：
1980
影响因子：
11.1
通讯作者：
Clough,W
中科院分区：
文献类型：
--
作者：
Clough,W
已从人B类淋巴母细胞中分离出一种内切核酸酶，该内切核酸酶具有核酸外切活性，并已显示在体外噬菌体λ DNA中产生双链断裂和高比例的单链性。数据是一致的模型，其中单链切割是由内切核酸酶活性，可能在A+ T-丰富的区域的DNA，随后创建的单链区域（缺口）从网站的切割旋进。在相反的链上产生重叠的缺口或在缺口的对面产生缺口将导致我们在电泳凝胶上看到的带型的产生。这种核酸内切活性与由爱泼斯坦-巴尔病毒诱导的其他酶共同纯化，这些酶与生产性感染细胞中的病毒DNA复制过程有关。然而，这类真核核酸内切酶活性被认为具有更普遍的作用。在许多真核生物的复制DNA中发现了显著程度的单链性，并且这些缺口可以由具有相关核酸外切活性的核酸内切酶产生，如本文所报道的。这种EB病毒诱导的核酸酶活性已显示类似于从原核生物大肠杆菌分离的recBC核酸酶以及从真核生物衣原体分离的内切核酸酶。
An endonuclease has been isolated from human B lymphoblastoid cells that copurifies with an exonucleolytic activity and has been shown to produce double-strand breaks and a high proportion of single-strandedness in phage lambda DNA in vitro. The data are consistent with a model in which single-strand cuts are made by the endonucleolytic activity, possibly in A+T-rich regions of the DNA, followed by creation of single-stranded regions (gaps) precessing from the site of a cut. Generation of overlapping gaps on opposite strands or of a gap opposite a nick would lead to the creation of the banding patterns that we have seen on electrophoretic gels. This endonucleolytic activity copurifies with other enzymes induced by Epstein-Barr virus that relate to the process of viral DNA replication in productively infected cells. However, a more general role is proposed for this class of eukaryotic endonuclease activities. A marked degree of single-strandedness has been found in the replicating DNAs of many eukaryotes, ad these gaps could be generated by endonucleases with associated exonucleolytic activity such as that reported here. This Epstein-Barr virus-induced nuclease activity has been shown to resemble the recBC nuclease isolated from the prokaryote Escherichia coli and also the endonuclease isolated from the eukaryote Chlamydomonas.