Hybridization Chain Reaction Based on Paranemic Crossover DNA.

Area of Science:

• * Molecular Biology
• * Nanotechnology
• * Nucleic Acid Chemistry

Background:

• * The classic hybridization chain reaction (HCR) typically forms linear DNA duplexes.
• * DNA nanostructures offer unique properties for various applications.
• * Developing novel DNA structures for controlled HCR is crucial.

Purpose of the Study:

• * To adapt hybridization chain reaction (HCR) for paranemic crossover (PX) DNA structures.
• * To investigate the use of PX structures as monomers for assembling DNA nanostructures.
• * To explore the potential of PX-based HCR for biosensing and complex DNA assembly.

Main Methods:

• * Design and synthesis of PX DNA structures with terminal loops and toeholds.
• * Study of isothermal strand displacement reactions on PX-loop structures.
• * Implementation of PX-based HCR using DNA and RNA initiators.
• * Optimization of RNA-initiated PX-HCR using 2'-OMe modifications.
• * Design of minimal paranemic cohesion PX structures for microRNA-triggered HCR.

Main Results:

• * PX structures successfully function as monomers in HCR, generating assembled nanostructures.
• * PX-based HCR can be initiated by both single-stranded DNA and RNA.
• * 2'-OMe modifications enhance RNA binding and optimize RNA-initiated PX-HCR kinetics.
• * MicroRNA-triggered PX-HCR demonstrates a rapid visible fluorescence response.
• * The strategy shows generality and potential for diverse applications.

Conclusions:

• * Paranemic crossover (PX) structures provide a versatile platform for hybridization chain reaction (HCR).
• * PX-based HCR facilitates the assembly of complex DNA nanostructures and enables facile initiation by both DNA and RNA.
• * The developed 2'-OMe modified PX strategy offers enhanced kinetics and sensitivity for microRNA detection, indicating broad potential in biosensing and DNA nanotechnology.