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：1974
卷号：71
期号：5
页码：2077-2081
DOI：10.1073/pnas.71.5.2077
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The action of restriction enzymes on polyoma DNA was studied with uniformly 32P-labeled viral DNA obtained from either infected 3T6 or secondary mouse-embryo cells. Three restriction enzymes were used to construct a physical map of the polyoma genome. An enzyme from Hemophilus parainfluenzae, HpaII, cleaved polyma DNA into eight unique fragments (HpaII-1 to HpaII-8), ranging in size from 27.3 to 1.8% of the genome. An enzyme from Hemophilus influenzae, HinIII, gave two fragments (56 and 44%); and a third enzyme from Escherichia coli, EcoRI, cut at a single unique site. The physical map of the polyma genome was constructed from methods involving: (1) further digestion of the fragments produced by enzymes EcoRI and HinIII with HpaII, and (2) analysis of the products of partial digestion with HpaII. Analysis by electron microscopy of replicating DNA molecules (less than 50% replicated) cut with the HinIII enzyme, in combination with other studies, has indicated that the origin of DNA replication is located at 71 {+/-} 3 map units from the EcoRI cleavage site, probably in HpaII-5.
关键词：polyma virus ; restriction enzymes ; origin of DNA replication ; T4 gene-32 protein
