Chapter 9: Replication of DNA genome Flashcards
How is viral DNA synthesized during cellular DNA replication
Viral DNA is synthesized by template-directed, stepwise incorporation of deoxynucleoside monophosphates (dNMPs) from deoxynucleoside triphosphate (dNTP) substrates into the 3′-OH end of the growing DNA chain.
What is the outcome of the replication of each parental strand in duplex DNA?
Each parental strand is copied by base pairing, producing two daughter molecules identical to one another and to their parent, known as semiconservative replication.
Where does DNA replication begin and end in the template?
DNA replication begins and ends at specific sites in the template, termed origins and termini, respectively.
How is viral DNA synthesis generally primed?
Viral DNA synthesis is generally primed by the 3′-OH group of an RNA primer, a dNMP covalently attached to a protein primer, or a specialized structure in the genomic DNA template.
What are the two modes of viral DNA replication?
Viral DNA replication occurs either by copying both strands at a replication fork or by copying each strand separately.
What are viral origins, and how are they recognized?
Viral origins are assembly points for DNA replication machines and are recognized by dedicated origin-binding proteins
What does viral DNA synthesis depend on?
Viral DNA synthesis depends on a combination of viral and cellular replication proteins; in some cases, all replication proteins are encoded in the viral genomes.
Where do viral DNA replication and transcription occur within the cell?
Viral DNA replication (and transcription) occur in discrete compartments within the cell, where the participating viral proteins are concentrated.
How is viral persistence maintained, and what are its characteristics?
During viral persistence, alternative replication mechanisms maintain viral genomes at low concentrations and partition them into daughter cells.
Why are double-stranded DNA viruses replicated with high fidelity?
Double-stranded DNA viruses are replicated with high fidelity because both cellular and viral DNA polymerases possess proofreading capability.
What drives viral diversity, and how does it relate to DNA replication?
Recombination drives viral diversity, and components of recombination systems may participate in viral DNA replication.
