A Dual-RNA Guided CasZ Gene Editing Technology

Patent Status

Additional Patents Pending

Brief Description

The CRISPR-Cas system is now understood to confer bacteria and archaea with acquired immunity against phage and viruses. CRISPR-Cas systems consist of Cas proteins, which are involved in acquisition, targeting and cleavage of foreign DNA or RNA, and a CRISPR array, which includes direct repeats flanking short spacer sequences that guide Cas proteins to their targets.  Class 2 CRISPR-Cas systems are streamlined versions in which a single Cas protein bound to RNA is responsible for binding to and cleavage of a targeted sequence. The programmable nature of these minimal systems has facilitated their use as a versatile technology that is revolutionizing the field of genome manipulation, so there is a need in the art for additional Class 2 CRISPR/Cas systems (e.g., Cas protein plus guide RNA combinations).

UC Berkeley researchers discovered a new type of Cas protein, CasZ.  (CasZ) is short compared to previously identified CRISPR-Cas endonucleases, and thus use of this protein as an alternative provides the advantage that the nucleotide sequence encoding the protein is relatively short.  The researchers have shown that the CRISPR CasZ protein and its variants can be used in a complex for specific binding and cleavage of DNA. The CRISPR CasZ complex utilizes a novel RNA and a guide RNA to perform double stranded cleavage of DNA and the complex is expected to have a wide variety of applications in genome editing and nucleic acid manipulation. 

Suggested uses

• Genome editing
• Genetic engineering
• Gene therapy
• Research tools (e.g., high-throughput screening of gene functions in cell lines and in vivo)
• Creation of transgenic animal models

Advantages

• Adds additional versatility because of small size
• Variant PAM