Cas12a分子背景
Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-associated endonuclease from Lachnospiraceae bacterium,Cas12a, also known as Cpf1, is a 1200-1500 amino-acids long monomeric protein that belongs to the CRISPR/Cas system , an adaptive immune system of prokaryotes that has now become a powerful tool for genome editing. CRISPR/Cas12a belongs the class II (type 5) of the CRISPR/Cas system that is defined by a single-subunit effector. Cas12a has recently emerged as an alternative for Cas9, due to its distinct features such as the ability to target T-rich motifs, no need for trans-activating crRNA, inducing a staggered double-strand break and potential for both RNA processing and DNA nuclease activity. In addition, Cas12a is able to process more structured pre-CRISPR/RNA(crRNA) molecules into mature crRNAs which allows the possibility to use both mature or pre-crRNA for genome editing purposes. All these features make the CRISPR/Cas12a system a valuable genome-engineering tool. CRISPR-Cas12a has been successfully used to edit genomes in many mammalians cells and plants.