The structure and gene products of an integrated retroviral genome. The retroviral RNA genome is flanked by long terminal repeats (LTRs), which contain sequences needed for the regulation and initiation of transcription. The primary retroviral transcript encompasses the gag, pol, and env genes as well as sequences on either side of those genes. Translation of the primary transcript yields two different polyproteins. One is derived only from the gag gene, and this polyprotein is cleaved into three different proteins that make up the viral core, matrix, and capsid. The second polyprotein, generated at lower levels, is derived from the gag and pol genes. This polyprotein is cleaved into six distinct proteins, including those derived from the gag gene as well as the reverse transcriptase, integrase, and protease derived from the pol gene. The primary transcript is spliced to generate a shorter transcript used for translation of the env gene. The polyprotein derived from the env gene is similarly cleaved to generate viral envelope proteins.