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：4
页码：1716-1720
DOI：10.1073/pnas.76.4.1716
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The DNA of the transducing phage lambdarifd18 contains, among others, the genes for the ribosomal proteins L11, L1, L10, and L12 and the beta and beta' subunits of RNA polymerase (nucleosidetriphosphate:RNA nucleotidyltransferase, EC 2.7.7.6 ). In a coupled in vitro protein-synthesis system, lambdarifd18 DNA directs the synthesis of about four to five molecules of L12 per molecule of L10. This is consistent with the finding that there are four copies of L12 per ribosome. The ratio of L12/L10 was also examined from an EcoRI fragment of lambdarifd18 that contains the L10 gene and about 50% of the L12 gene. A significantly lower ratio of truncated L12/L10 was observed compared to the intact phage. The binding of RNA polymerase to various lambdarifd18 DNA restriction fragments was used to locate possible promoter sites. These binding experiments suggest that the beta and beta' subunits of RNA polymerase are cotranscribed with at least ribosomal protein L12 and, also, that there may be an additional promoter site for the L12 gene within the structural gene for L10.
