Probing Y-shaped DNA structure with time-resolved FRET.

Area of Science:

• Biomolecular Engineering
• Nanotechnology
• Structural Biology

Background:

• Nucleic acid self-assembly offers programmable matter fabrication via molecular recognition.
• Y-shaped DNA (Y-DNA) serves as a versatile building block for complex nanoscale architectures.
• The stability of Y-DNA influences the precise control over nano- and microstructures.

Purpose of the Study:

• To investigate the structural integrity and configurational stability of Y-DNA systems.
• To establish Y-DNA as a reliable component for bottom-up fabrication.
• To determine the thermal stability limits of Y-DNA nanoarchitectures.

Main Methods:

• Utilized time-resolved Förster resonance energy transfer (FRET) to probe Y-DNA structure.
• Incorporated a fluorophore (Alexa 488) and an acceptor (DABCYL) at distinct Y-DNA ends.
• Measured fluorophore lifetime to determine donor-acceptor distances and assess configurational changes.

Main Results:

• Confirmed distinct distances between Y-DNA arms, indicating structural integrity.
• Demonstrated Y-DNA's suitability as a foundational element for molecular self-assembly.
• Identified configurational changes in Y-DNA nanoarchitecture occurring above 40 °C.

Conclusions:

• Y-DNA exhibits robust structural integrity essential for programmable self-assembly.
• The thermal stability threshold of 40 °C is a critical parameter for designing Y-DNA-based nanostructures.
• These findings support Y-DNA's role in advancing bottom-up fabrication of functional nanomaterials.