Related Experiment Video
Updated: Jun 22, 2025
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Assessment of Immunologically Relevant Dynamic Tertiary Structural Features of the HIV-1 V3 Loop Crown R2 Sequence by ab initio Folding
Published on: September 15, 2010
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Cas12a domain flexibility guides R-loop formation and forces RuvC resetting
Isabel Strohkendl1, Aakash Saha2, Catherine Moy1
1Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA.
Molecular Cell
|July 2, 2024
Summary
CRISPR-Cas12a
Area of Science:
- Molecular Biology
- Structural Biology
- Biotechnology
Background:
- CRISPR-Cas12a is an RNA-guided endonuclease with significant potential in biotechnology and therapeutics.
- Understanding its mechanism is crucial for optimizing its applications.
Purpose of the Study:
- To elucidate the structural mechanisms of CRISPR-Cas12a's DNA targeting and nuclease activation.
- To detail the R-loop formation process and its role in target recognition.
Main Methods:
- Cryo-electron microscopy (cryo-EM) was employed to visualize Cas12a R-loop intermediates.
- Structural analysis captured dynamic stages of DNA binding and cleavage.
Main Results:
- Distinct REC domain arrangements correlate with R-loop formation stages.
- Domain flexibility facilitates non-target strand engagement and subsequent cleavage.
- Target strand repositioning and RuvC active site occlusion/resetting were observed.
Conclusions:
- A structural model for Cas12a DNA targeting, R-loop formation, and cleavage was established.
- The findings provide mechanistic insights into Cas12a specificity and compare it to other Class 2 CRISPR effectors.
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