Group II intron retrohoming. In the first step, the reverse transcriptase (RT) binds to the intron in a larger initial transcript of a gene and promotes RNA splicing, resulting in a ribonucleoprotein (RNP) complex that contains the excised intron lariat RNA and the tightly bound RT. RNPs recognize DNA target sites by using both the RT and base pairing of the intron RNA and then promote reverse splicing of the intron RNA into the top strand of the double-stranded DNA. After reverse splicing, the bottom DNA strand is cleaved by the En domain of the RT, and the 3’ end generated at the cleavage site is used as a primer for target DNA-primed reverse transcription of the inserted intron RNA. The resulting intron cDNA (black) is integrated into the host genome by cellular DNA recombination or repair mechanisms.