provirus The intermediate stage in the infection of a host cell by a virus, e.g. a retrovirus, in which the viral genome is integrated into the DNA of the host, where it can undergo successive replications before being transcribed. In the case of retroviruses the single RNA strand of the virus is converted into double-stranded DNA by the enzyme reverse transcriptase, then integrated into the host cell DNA and subsequently transcribed to form new RNA viruses. This integration also introduces retroviral oncogenes into the host, with the attendant risk of host-cell transformation to a cancer cell. A provirus, notably that of HIV, can remain dormant for long periods before being transcribed. See also prophage.

provirus A viral genome which is incorporated into a host genome.

provirus A viral genome which is incorporated into a host genome.