Table of Contents
How do single-stranded DNA viruses replicate?
Single-stranded (ss)DNA viruses are extremely widespread, infect diverse hosts from all three domains of life and include important pathogens. Most ssDNA viruses possess small genomes that replicate by the rolling-circle-like mechanism initiated by a distinct virus-encoded endonuclease.
How do you replicate RNA?
RNA replication is the process by which new copies of genome-length RNAs are made (figure 8). RNA replication occurs in the cytoplasm and is carried out by the viral RNA polymerase….
| PROPERTY | PARAMYXOVIRIDAE | ORTHOMYXOVIRIDAE |
|---|---|---|
| RNA synthesis | cytoplasmic | nuclear |
| Need for mRNA primer | no | yes |
How does RNA replicate simple?
During RNA replication, the gene-start and gene-end signals are ignored and an exact complementary copy of the genome (antigenome) is synthesized. RNA synthesis is tightly linked to encapsidation of the progeny molecule. A promoter located at the 3′ end of the antigenome is used to synthesize genome.
Can single-stranded DNA replicate?
Certain small bacteriophages contain a circular, single-stranded DNA (ssDNA) as genome. Thus, replication of the ssDNA genome depends on the synthesis by DNA polymerase of a complementary strand in a sophisticated manner. …
How do double stranded RNA viruses replicate?
Double-stranded RNA virus replication Upon infection, the genomic dsRNA is transcribed in mRNAs that will both serve for translation and/or replication. mRNAs translation produces the proteins necessary to ensure replication and encapsidation. Replication occurs in host cytoplasm and converts ss-mRNA to ds-genomic RNA.
Which RNA is responsible for replication?
As complex molecule composed of protein subunits, RNA polymerase controls the process of transcription, during which the information stored in a molecule of DNA is copied into a new molecule of messenger RNA.
How does DNA and RNA replicate?
DNA replication initiates at specific points, called origins, where the DNA double helix is unwound. A short segment of RNA, called a primer, is then synthesized and acts as a starting point for new DNA synthesis. An enzyme called DNA polymerase next begins replicating the DNA by matching bases to the original strand.
Can RNA be single stranded?
Although RNA is a single-stranded molecule, researchers soon discovered that it can form double-stranded structures, which are important to its function. Such base-pairing of RNA is critical for many RNA functions, such as the ability of tRNA to bind to the correct sequence of mRNA during translation (Figure 3).
How do RNA viruses replicate?
DNA viruses only replicate when the cell is actively divide g or if the virus has the right machinery to force the cell to enter into a reproductive stage. RNA on the other hand is produced all the time in a cell. so RNA viruses are less dependent on the host cells being in a particular stage of its replication cycle.
What is a positive strand of RNA?
Positive-strand RNA virus: Also known as a sense-strand RNA virus, a virus whose genetic information consists of a single strand of RNA that is the positive (or sense) strand which encodes mRNA (messenger RNA) and protein. Replication in positive-strand RNA viruses is via a negative-strand intermediate.
What are the steps of DNA to RNA?
There are three main steps to the process of DNA transcription: RNA Polymerase Binds to DNA. DNA is transcribed by an enzyme called RNA polymerase. Specific nucleotide sequences tell RNA polymerase where to begin and where to end. RNA polymerase attaches to the DNA at a specific area called the promoter region.
How does RNA replicate?
As it happens, RNA does not replicate itself, except in specific exceptions. RNA is usually produced by the “copying” of strands of DNA, and other strands can be found in ribosomes , which typically do not replicate themselves either.