Reverse transcriptase is an enzyme that copies single stranded DNA into double stranded DNA.

Reverse Transcriptase enzyme

Reverse Transcriptase Enzyme

It is an RNA-dependent DNA polymerase that is used in the viral replication because they can only replicate their DNA when they are inside the host\’s cell. While the enzyme synthesizes DNA in the unprotected host cells, it is bound to the target cell by the enzyme.

But there is a problem, the target cell\’s DNA has to first be broken down into short single stranded pieces of DNA. The enzyme does this by breaking down the target cell\’s DNA at \”start\” points.

In the process of doing this, the enzyme also introduces an RNA primer and a DNA chain that can be used to reconstruct the original chain. The enzyme is evolved from a similar protease that is made to destroy RNA, but is altered to destroy DNA instead.