Table 1.
Characteristics of different types of clustered regularly interspaced short palindromic repeats (CRISPR) systems.
| Characteristic | Type I | Type II | Type III | Type IV | Type V | Type VI |
|---|---|---|---|---|---|---|
| Effector complex | Multisubunit (Class 1) | Single unit (Class 2) | Multisubunit (Class 1) | Multisubunit (Class 1) | Single unit (Class 2) | Single unit (Class 2) |
| Signature Protein | Cas3 | Cas9 | Cas10 | Csf1 | Cas12 | Cas13 |
| Target molecule | DNA | DNA | RNA/DNA | ? | DNA | RNA |
| Details | Cleaves ssDNA strands | Originates blunt DSB | Binds to nascent RNA molecules | Most unknown CRISPR system | Originates staggered DSB | RNA-guided RNase |