Cas12a: enhancing the capability of CRISPR technologies
Cas12a has been used for the first time in a preclinical cancer model, representing a significant advancement in gene editing.
Researchers at the Olivia Newton-John Cancer Research Institute (Melbourne, Australia), Walter and Eliza Hall Institute of Medical Research (WEHI; Parkville, Australia), and Genentech (CA, USA) have established Cas12a as a next-generation gene-editing tool. The Cas12a enzyme could provide a more effective approach in CRISPR technology for advanced genetic studies, including complex disease modeling and therapy development for diseases.
CRISPR technology has transformed cancer research by enabling precise gene editing, primarily through the Cas9 enzyme, which cuts specific sections of DNA and RNA. While CRISPR-Cas9 has led to major discoveries and is being explored for clinical applications, Cas12a offers unique advantages, including precise multi-gene editing.
This study is the first to establish Cas12a’s use in a preclinical cancer model, demonstrating its potential to enhance genome engineering.
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To explore Cas12a’s potential, the researchers used an advanced Cas12a-expressing mouse model with a fluorescent reporter. Their approach enabled precise single-gene editing, simultaneous deletion of faulty genes and activation of beneficial ones in vitro, and successful in vivo gene editing by reconstructing the blood system of healthy mice using both normal and cancer-prone Cas12a stem cells.
Building on this, the team developed Cas12a-compatible whole-genome CRISPR libraries, enabling systematic gene disruption. These compact libraries included Scherzo and Menuetto vectors. With these libraries, they conducted in vitro enrichment and drop-out screening in lymphoma cells and immortalized fibroblasts – fibroblasts altered to proliferate indefinitely – along with in vivo screens in mice. This approach led to the identification of genes that drive lymphoma development, demonstrating the system’s capability of identifying cancer-related genetic factors.
In addition, they combined their Cas12a model with a separate system expressing a modified Cas9 (dCas9-SAM), allowing for simultaneous gene deletion through Cas12a and gene activation through dCas9-SAM. By integrating Cas12a with other gene-editing tools, the researchers developed a system capable of simultaneously deleting faulty genes and activating beneficial ones, expanding the potential of gene editing.
These findings highlight the advantages of Cas12a and its compatible libraries, offering an improved approach that complements existing CRISPR technologies.
The team is now exploring how their model can support the development of CRISPR-based therapies, aiming to improve gene-editing techniques and overcome challenges in clinical applications.
Marco Herold, CEO of the Olivia Newton-John Cancer Research Institute and Head of the La Trobe University School of Cancer Medicine (Melbourne, Australia), said:
“We are certain that this work will encourage other research teams to use this Cas12a pre-clinical model which, in combination with the screening libraries, are a powerful new suite of gene-editing tools to improve our understanding of the mechanisms behind many different cancers.”
