Related Experiment Video
Updated: Aug 6, 2025
09:51
Enhanced Genome Editing with Cas9 Ribonucleoprotein in Diverse Cells and Organisms
Published on: May 25, 2018
34.2K
PAM-Flexible Genome Editing with an Engineered Chimeric Cas9
Sabrina Koseki1, Lauren Hong1, Vivian Yudistyra1
1Duke University.
Research Square
|March 22, 2023
Summary
Researchers engineered a new CRISPR enzyme, SpRYc, by combining two Cas9 variants. This novel enzyme broadens genome editing capabilities by targeting diverse PAM sequences, enabling precise gene modification for therapeutic applications.
Area of Science:
- Biotechnology
- Molecular Biology
- Genomics
Background:
- CRISPR-Cas9 systems require specific protospacer adjacent motifs (PAMs) for DNA targeting.
- Limited PAM accessibility restricts the application of CRISPR genome editing.
Approach:
- Engineered a chimeric Cas9 enzyme, SpRYc, by fusing the PAM-interacting domain of SpRY with the N-terminus of Sc++.
- SpRY has an NRN > NYN PAM preference, while Sc++ offers broad, efficient, and accurate NNG editing.
Key Points:
- SpRYc exhibits a highly flexible PAM preference, enabling editing of diverse NNN PAMs.
- Demonstrated specific editing of disease-related loci using SpRYc.
- The chimeric enzyme leverages the strengths of both parent Cas9 variants.
Conclusions:
- Integrative protein design is a powerful strategy for advancing Cas9 engineering.
- SpRYc's flexibility opens new avenues for precise genomic positioning in therapeutic applications.
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