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：8
页码：3829-3833
DOI：10.1073/pnas.76.8.3829
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Hybrid ColE1 plasmids, containing cloned DNA from the yeast ARG4 region [e.g., pYe(arg4)1], transform yeast arg4 mutants to ARG4+ with a frequency of 10-4 (about 103 transformants per {micro}g of plasmid DNA) and can replicate autonomously without integrating into the yeast genome. The yeast transformants are genetically unstable when grown on nonselective medium, but can be readily grown and maintained on minimal medium lacking arginine. The existence of unintegrated replicating plasmid DNA in the yeast transformants was demonstrated by Southern gel hybridization and by transformation of Escherichia coli argH mutants with DNA preparations from yeast transformants and subsequent recovery of intact plasmid DNA from the bacterial transformants. Plasmid DNAs recovered from the E. coli-yeast-E. coli "shuttle" remain essentially unchanged, as judged by DNA restriction fragment patterns. Some plasmid mutations leading to increased efficiency of expression of the ARG4 gene in E. coli do not appear to affect expression of the cloned ARG4 gene in yeast. Appropriate derivatives of these ARG4 plasmids are of potential usefulness as vectors for cloning genes in yeast and for studying the mechanism of yeast DNA replication.
