RNA Strand Displacement Responsive CRISPR/Cas9 System for mRNA Sensing

Area of Science:

• Molecular Biology
• Synthetic Biology
• Biotechnology

Background:

• CRISPR/Cas9 is a versatile tool for genomic manipulation.
• Existing stimuli-responsive CRISPR systems often rely on engineered Cas9 proteins and limited external signals.
• There is a need for more precise, easily constructed, and broadly responsive CRISPR systems.

Purpose of the Study:

• To engineer conditional guide RNA (gRNA) for stimuli-responsive CRISPR systems.
• To develop a CRISPR system that responds to mRNA inputs via logic operations.
• To broaden the responsive species and applications of CRISPR technology.

Main Methods:

• gRNA reconfiguration and toehold-mediated strand displacement were employed.
• mRNA-sensing CRISPR systems were constructed with independently controllable target sites.
• NOR and NAND logic gates were implemented using the engineered gRNA.

Main Results:

• Conditional gRNA was successfully engineered to act as RNA sensors.
• The system demonstrated orthogonal detection of multiple mRNA inputs.
• Programmable CRISPR/Cas9 response outputs and logic gates (NOR, NAND) were achieved.

Conclusions:

• The developed strategy enables the construction of precise and programmable mRNA-sensing CRISPR systems.
• This approach offers a new method for engineering genetic circuits to detect endogenous mRNAs.
• The technology holds potential for initiating specific cellular responses based on mRNA detection.