What does provirus mean?
A provirus is viral genetic material that has become integrated into the genome of a host cell. The term is especially associated with retroviruses, including HIV: after viral RNA is converted into DNA, that DNA can be inserted into a chromosome, where it is called a provirus. It may remain inactive and undetected, yet retain the capacity to produce new virus under some circumstances. Because the integrated genetic material occupies part of the host genome, it may also be inherited by daughter cells when the cell divides. In broader technical usage, provirus can refer more generally to viral DNA integrated into a cellular genome, though this usage is less common. The word is important in discussions of viral latency, disease persistence, gene therapy, and the molecular mechanisms of retroviral infection.
nounA copy of a viral genome integrated into the genome of a host cell. In particular, it refers to the DNA form of a retrovirus after it has entered the host genome.
- A viral genome, especially that of a retrovirus, integrated into the DNA of a host cell.
"The provirus remained dormant in the cell until the virus began actively replicating."
"Researchers identified a dormant provirus within the patient's immune cells."
"The retrovirus can integrate into the host chromosome to form a provirus."
The plural is uncommon because the word normally appears in technical descriptions and singular contexts.
"The researchers detected multiple proviruses in the viral reservoir."
A provirus hides inside a cell's own DNA, becoming part of the host's genome and potentially passing down to its descendants.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does provirus come from?
Provirus was formed in the 20th century from the prefix pro-, meaning “before” or “in front of,” and virus. The latter comes through scientific Latin from Latin virus, an older word associated with poison or harmful material. The compound was coined for the integrated stage of a retroviral infection rather than for the free infectious particle.
Related word forms
How provirus is actually used
This is a technical molecular-biology term. It is most often used with retroviruses such as HIV, although analogous integrated viral genomes may also be described as proviruses.
Easily confused with provirus
A virus is the complete infectious particle, whereas a provirus is viral genetic material integrated into the genome of a host cell.
A virion is a free or released viral particle, while a provirus is the integrated form of viral DNA within a host genome.