Evidence for the nuclear origin of RNA polymerases identified in the cytosol: release of enzymes from the nuclei isolated in isotonic sucrose.
Evidence for the nuclear origin of RNA polymerases identified in the cytosol: release of enzymes from the nuclei isolated in isotonic sucrose.
复制标题
细胞质中鉴定的 RNA 聚合酶核起源的证据：从等渗蔗糖中分离的细胞核释放酶。
DOI：
10.1016/0006-291x(76)90968-2
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发表时间：
1976
影响因子：
3.1
通讯作者：
S. Jacob
中科院分区：
文献类型：
--
作者：
Y. C. Lin;K. Rose;S. Jacob
从等渗或高渗蔗糖中分离的大鼠肝核中提取dna依赖性RNA聚合酶，并进行层析。高渗核的RNA聚合酶I、II和III的活性分别是等渗核的3.8倍、1.5倍和27倍。RNA聚合酶III在“等渗核”中几乎不存在。随着从“等渗核”中聚合酶的回收率降低，相应的细胞质组分含有较高水平的所有三种酶。这些研究为先前在“等渗细胞质”部分中发现的大部分细胞质RNA聚合酶C与核RNA聚合酶III相对应的论点提供了强有力的证据。这些数据表明，为了防止核酶的泄漏，需要在组织的初始均质中使用高渗蔗糖。
DNA-dependent RNA polymerases were extracted from rat liver nuclei isolated in isotonic or hypertonic sucrose and resolved chromatographically. Activities of RNA polymerases I, II and III from “hypertonic nuclei” were 3.8, 1.5 and 27-fold, respectively, higher than those from “isotonic nuclei”. RNA polymerase III was virtually absent in the “isotonic nuclei”. Concurrent with the reduced revovery of polymerases from the “isotonic nuclei”, the corresponding cytosol fraction contained higher levels of all three enzymes. These studies provide strong evidence for the contention that a large proportion of cytoplasmic RNA polymerase C previously identified in “isotonic cytosol” fraction corresponds to nuclear RNA polymerase III. These data demonstrate the need for the use of hypertonic sucrose in the initial homogenization of tissues in order to prevent leakage of the nuclear enzymes.