HIV attaches to and penetrates host T cells, then releases HIV RNA and enzymes into the host cell. HIV reverse transcriptase copies viral RNA as proviral DNA. Proviral DNA enters the host cell’s nucleus, and HIV integrase facilitates the proviral DNA’s integration into the host’s DNA. The host cell then produces HIV RNA and HIV proteins. HIV proteins are assembled into HIV virions and budded from the cell surface. HIV protease cleaves viral proteins, converting the immature virion to a mature, infectious virion.