Figure 1.

Cas12a and Cas12e belong to Class II Type V CRISPR-Cas effectors, subtypes V-A and V-E, correspondingly.

In contrast to Cas12a, Cas12e enzymes require tracrRNA in addition to crRNA for DNA target recognition. crRNA indicated in red, tracrRNA indicated in green. PAM sequences are shown with blue rectangles. SpCas9 – Cas9 from Streptococcus pyogenes (1,368 amino acids), AsCas12a – Cas12a from Acidaminococcus sp. (1,307 amino acids), DpbCas12e – Cas12e from Deltaproteobacteria (986 amino acids). The pairing between DNA and RNA molecules, as well as indicated positions of DNA cleavage sites shown are schematic.