An Engineered Hypercompact CRISPR-Cas12f System with Boosted Gene-Editing Activity

SUMMARY

The engineered hypercompact enAsCas12f system addresses CRISPR-Cas systems deliverability issues while offering enhanced gene-editing high specificity making it ideal for therapeutic applications using AAV delivery.

The unmet Need: New CRISPR-systems with greater deliverability and higher gene editing capabilities

• CRISPR-Cas (clustered regularly interspaced short palindromic repeats and CRISPR-associated proteins) systems have revolutionized genome engineering, offering the potential for targeted therapies for genetic disorders. The in vivo application of these systems hinges on safe and efficient delivery methods, with adeno-associated viruses (AAVs) emerging as leading candidates due to their established safety profile and versatility. However, the limited packaging capacity of AAV vectors (4.7 kb) poses a significant challenge for delivering larger CRISPR systems like SpCas9 (1,368 amino acids) or AsCas12a (1,307 amino acids) along with their necessary components.

• This limitation has spurred interest in compact CRISPR-Cas systems, particularly Cas12f proteins, which are significantly smaller. While promising, existing compact CRISPR-Cas systems, including Cas12f, often exhibit modest gene-editing activity compared to their larger counterparts. This reduced activity limits their therapeutic efficacy and necessitates further development to achieve robust and reliable gene editing for clinical applications.

The proposed solution: Potent and versatile engineered hypercompact enAsCas12f with enhanced gene-editing efficiency

• The faculty inventor developed enAsCas12f, an engineered CRISPR-Cas12f system designed for enhanced gene editing in-human cells. This system boasts significantly higher potency, up to 11.3 times, compared to its predecessor, AsCas12f. It is remarkably compact, approximately one-third the size of the widely used SpCas9, making it ideal for delivery via adeno-associated viruses (AAVs) that have limited packaging capacity. enAsCas12f achieves impressive insertion and deletion rates of up to 69.8% at targeted genomic locations while exhibiting minimal off-target effects, ensuring high specificity.

FIGURE

ADVANTAGES

ADVANTAGES

• Significantly more potent (up to 11.3x) than its parent protein, AsCas12f

• Minimal off-target effects

• High specificity

• Compact, one-third the size of SpCas9

• AAV deliverability

APPLICATIONS

• Gene therapy
• Drug discovery

PUBLICATIONS

• Wu, T., Liu, C., Zou, S. et al. An engineered hypercompact CRISPR-Cas12f system with boosted gene-editing activity. Nat Chem Biol 19, 1384–1393 (2023). https://doi.org/10.1038/s41589-023-01380-9

October 21, 2024

Proof of concept

Patent Pending

Licensing,Co-development

Weixin Tang