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How does a retrovirus use a host cell’s genetic machinery after making proviral DNA?

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Diagram illustrating the process of retrovirus infection and reverse transcription, showing a retrovirus entering a host cell, releasing viral RNA, reverse transcriptase converting RNA to DNA, integration into the host genome, transcription of new viral RNA, assembly of new virions, and budding from the cell. — Reverse transcriptase After a retrovirus infects a cell, an enzyme known as reverse transcriptase converts viral RNA into proviral DNA in the cytoplasm. Proviral DNA then enters the nucleus, where it is incorporated into the host cell's DNA.

After a retrovirus uses reverse transcriptase to convert its RNA genome into proviral DNA, the viral enzyme integrase facilitates the insertion of this DNA into the host cell's chromosomal DNA.12

Once integrated, the viral genes become a permanent part of the host genome and are transcribed by the cell's own genetic machinery as if they were native genes. The host cell then utilizes these instructions to produce new viral components:13

Viral RNA: Some of the transcribed RNA molecules are packaged into new virus particles to serve as the viral genome.3
Viral Proteins: Other RNA molecules act as messenger RNA (mRNA), which the host cell translates into the proteins necessary to assemble new virions.13

These components eventually assemble at the host cell's plasma membrane, where new virus particles bud off to infect other cells. This process effectively hijacks the cell's resources to sustain the retroviral life cycle.31