Description

A retrovirus is an RNA virus that replicates in a host cell using its reverse transcriptase enzyme to produce DNA from its RNA genome. The viral DNA is then incorporated into the host's genome by an integrase enzyme. The virus thereafter replicates as part of the host cell's DNA. Retroviruses are enveloped viruses that belong to the viral family Retroviridae. (Kurth, R. et al. 2010) In most viruses, DNA is transcribed into RNA, and then RNA is translated into protein. However, retroviruses function differently - their RNA is reverse-transcribed into DNA, which is integrated into the host cell's genome (when it becomes a provirus), and then undergoes the usual transcription and translational processes to express the genes carried by the virus. So, the information contained in a retroviral gene is used to generate the corresponding protein via the sequence: RNA → DNA → RNA → protein.