Retrovirus-related Pol polyprotein (Pol)

Has a reverse transcriptase activity needed for target-primed reverse transcription of the LINE-1 element mRNA, a vital step in LINE-1 retrotransposition. Has also an endonuclease activity which allows the introduction of nicks in the chromosomal target DNA.

Cleaves DNA in AT-rich regions between a 5' stretch of purines and a 3' stretch of pyrimidines, corresponding to sites of LINE-1 integration in the genome. .