Cas12a

CRISPR-associated protein 12a
Acidaminococcus sp. Cas12a PDB: 5B43​
Identifiers
Symbol	Cas12a
InterPro	IPR027620

Cas12a (CRISPR-associated protein 12a, previously known as Cpf1) is an RNA-guided endonuclease that forms an essential component of the CRISPR systems found in some bacteria and archaea. In its natural context, Cas12a targets and destroys the genetic material of viruses and other foreign mobile genetic elements, thereby protecting the host cell from infection. Like other Cas enzymes, Cas12a binds to a "guide" RNA (termed a crRNA, or CRISPR RNA) which targets it to a DNA sequence in a specific and programmable matter. In the host organism, the crRNA contains a constant region that is recognized by the Cas12a protein and a "spacer" region that is complementary to a piece of foreign nucleic acid (e.g. a portion of a phage genome) that previously infected the cell.^[1]

As with Cas9 and other Cas proteins, the programmable DNA-targeting activity of Cas12a makes it a useful tool for biotechnology and biological research applications. By modifying the spacer sequence in the crRNA, researchers can target Cas12a to specific DNA sequences, allowing for highly targeted modifications of DNA.^[2] Cas12a is distinguished from Cas9 by a its single RuvC endonuclease active site, its 5' protospacer adjacent motif preference, and its formation of sticky rather than blunt ends at the cut site; these and other differences may make it more suitable for certain applications^{[citation needed]}. Beyond its use in basic research, CRISPR-Cas12a could have applications in the treatment of genetic illnesses and in implementing gene drives.^[2]