The Replication of Polyoma DNA

The replication of polyoma DNA.

Polyoma virus DNA replication is semi-discontinuous.

In marked contrast to simian virus 40 (SV40), polyoma virus (PyV) has been reported to replicate discontinuously on both arms of replication forks. In an effort to clarify the relationship between the mechanisms of DNA replication in these closely related viruses, the distribution of RNA-primed DNA chains at replication forks was examined concurrently in PyV and SV40 replicating DNA purified fr...

Tandem repetition of the origin of DNA replication in defective polyoma virus DNA's.

The sequences derived from the polyoma virus genome which are tandemly repeated in a class of noninfectious covalently closed circular DNA’s (Folk, W. R., and Wang, H. E., Virology 61, 140-155 (1974) have been identified. Specific fragments of polyoma DNA produced by cleavage with the HpaII endonuclease have been purified, and the homology between each fragment and the noninfectious DNA’s conta...

Regulatory mutants of polyoma virus defective in DNA replication and the synthesis of early proteins.

In polyoma virus the origin of replication, the 5’ ends of early mRNAs, and the initiation codon for early protein synthesis map within an approximately 200 bp region of the genome. We have previously reported the isolation and partial characterization of viable mutants of polyoma virus with deletions in this important regulatory region of the genome. Three of the mutants with large deletions, ...

Discontinuous synthesis of both strands at the growing fork during polyoma DNA replication in vitro.

In discontinuous polyoma DNA replication, the synthesis of Okazaki fragments is primed by RNA. During viral DNA synthesis in nuclei isolated from infected cells, 40% of the nascent short DNA fragments had the polarity of the leading strand which, in theory, could have been synthesized by a continuous mechanism. To rule out that the leading strand fragments were generated by degradation of nasce...