How are retroviruses and retrotransposons similar? Describe the genes encoded by the DNA of the retrovirus and the two DNA elements consistently found in retrotransposons

Question

What will be an ideal response?

Answer 1

Retroviruses are viruses that infect eukaryotic cells and have a genome consisting of single-stranded RNA. On infection, the RNA is transcribed into double-stranded DNA by reverse transcriptase, and the DNA is then integrated into a chromosome of the infected plant or animal cell. Integrated retroviral DNA encodes three genes, called gag, env, and pol. Gag and env encode proteins that form the retroviral particle, while the pol gene encodes the enzyme reverse transcriptase.
Retrotransposons are transposable elements and are related to retroviruses. They also have the pol gene, and some contain gag, but none have env. Thus retrotransposons are able to synthesize double-stranded DNA from single-stranded RNA and can transpose the DNA throughout the genome, but they do not possess the ability to produce protein particles.
Two constant features of retrotransposons are that they all have a pol gene encoding reverse transcriptase and retrotransposons are flanked by long terminal repeats (LTRs).