Pre-fork synthesis: a model for DNA replication.
نویسندگان
چکیده
A model of DNA replication is presented in which DNA synthesis is continuously initiated from parental strand nicks and occurs, with conservation of helix winding number, ahead of the so-called replicating fork. The fork in this model is the locus of unwinding of already replicated, but presumably unstable, DNA. The model, involving Okazaki's notion of multiple initiation, is based upon the properties of Kornberg's DNA polymerase and accounts for the presence of single-stranded nascent DNA fragments in cell lysates. In addition to acting as sites of initiation, the parental strand nicks are implicated as sites of free rotation allowing unwinding of the replicated DNA.
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عنوان ژورنال:
- Proceedings of the National Academy of Sciences of the United States of America
دوره 64 3 شماره
صفحات -
تاریخ انتشار 1969