Fig 2. Key host factors accessory functions in the retrohoming pathway of RmInt1.

Two headed arrow indicates the replication fork progression. RmInt1 RNP complexes recognize the target site on single-stranded DNA linked to DNA replication, involving invasion of the DNA strand that serves as a template for lagging strand synthesis. The reverse transcription of the inserted intron RNA could be primed by RNA primers (zigzag dashed lines), synthesized by the primase, or partial polymerization of the Okazaki fragments by DNA polymerase III. As an example, we represented the RmInt1 insertion beside the RNA primer. Intron RNA is shown as a dashed line. Enzymes found in this work are highlighted on grey rectangles, and their putative sites of action [facilitatory (+) and inhibitory (-) roles] are indicated by dotted arrows.