期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1979
卷号：76
期号：1
页码：136-140
DOI：10.1073/pnas.76.1.136
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：When incubated with a soluble extract from large oocytes of Xenopus laevis, recombinant DNA plasmids containing either X. laevis oocyte 5S DNA or X. borealis oocyte 5S DNA direct the synthesis of discrete 5S RNAs, which by size and sequence analysis are similar or identical to the corresponding 5S RNAs synthesized in vivo. Synthesis of the 5S RNAs is mediated by a soluble endogenous RNA polymerase III (nucleosidetriphosphate:RNA nucleotidyltransferase, EC 2.7.7.6 ), which presumably recognizes specific initiation and termination sites in the 5S genes. Optimal conditions for accurate synthesis and the kinetics of the reactions have been determined. A soluble postchromatin supernatant fraction has also been isolated from immature oocytes. Although devoid of a functional endogenous RNA polymerase III, this extract contains a component(s) that effects the accurate transcription of 5S genes (in a plasmid) by a purified RNA polymerase III.
