From: Targeting miRNA by CRISPR/Cas in cancer: advantages and challenges
CRISPR/Cas system | Types of Cas | Organism isolated from | Major application area | PAM sequence | PAM location relative to target base | Cas size (in amino acids) | References |
---|---|---|---|---|---|---|---|
Type II CRISPR/Cas system | SpCas9 | Streptococcus pyogenes | Gene editing | NGG | Downstream of the target site | 1368 AA | [171] |
xCas9 | Modified from SpCas9 | Gene editing | NG, GAA and GAT | Downstream of the target site | 1368 AA | [107] | |
SaCas9 | Staphylococcus aureus | Gene editing | NGRRT or NGRRN | Downstream of the target site | 1058 AA | [172] | |
SaCas9-KKH | Staphylococcus aureus Cas9 | Gene editing | NNNRRT | Downstream of the target site | 1058 AA | [173] | |
StCas9 | Streptococcus thermophilus | Gene editing | NNAGAAW | DSBs | 1121 AA | [174] | |
ScCas9 | Streptococcus canis | Gene editing | NNG | Downstream of the target site | 1375 AA | [175] | |
CjCas9 | Campylobacter jejuni | Efficient genome editing | NNNVRYM | Downstream of the target site | 984 AA | [176] | |
Type V CRISPR/Cas system | LbCas12a | Lachnospiraceae bacterium | Gene editing and diagnosis | TTTV | Upstream of the target site | 1228 AA | [177] |
enAsCas12a | Streptococcus pyogenes | Gene editing and diagnosis | TTTV | Upstream of the target site | – | [178] | |
Cas12f | Selenomonas sputigena | Diagnosis | TTTV | Double strand cleavage | 422–603 AA | [154] | |
Type V CRISPR/Cas system | Cas14b | Extremophile archaea | Gene editing and diagnosis | T-rich PAM sequences, e.g., TTTA for dsDNA cleavage, no PAM sequence requirement for ssDNA | Upstream of the target site | 400–700 AA | [141] |
Type I CRISPR/Cas system | Cas3 | Escherichia coli | Diagnosis | No PAM sequence requirement | Upstream of the target site | 1224 | [179] |