Accelerating SNARE-Mediated Membrane Fusion by DNA-Lipid Tethers

Area of Science:

• Biochemistry
• Molecular Biology
• Synthetic Biology

Background:

• SNARE proteins mediate vesicle-target membrane fusion, a critical cellular process.
• Tethering proteins naturally bridge membranes, facilitating SNARE complex assembly and fusion.
• Existing methods for controlling membrane fusion are limited in programmability and orthogonality.

Purpose of the Study:

• To develop a synthetic tool for regulating SNARE-mediated membrane fusion in situ.
• To investigate the effect of DNA-lipid tethers on the kinetics of liposome fusion.
• To establish a programmable platform for controlling membrane-associated biological processes.

Main Methods:

• Design and synthesis of lipid-conjugated single-stranded DNA (ssDNA) tethers.
• Utilizing DNA base-pairing for specific liposome bridging.
• Varying linker length to control inter-liposome distance.
• Quantifying SNARE-mediated lipid mixing and fusion rates.

Main Results:

• DNA-lipid tethers significantly accelerated SNARE-mediated lipid mixing.
• Optimal fusion rates were achieved with linker lengths shorter than 40 nucleotides.
• The DNA-lipid tethers demonstrated programmability and orthogonality to native proteins.
• Successful application in regulating membrane bridging for subsequent protein function.

Conclusions:

• Lipid-conjugated ssDNA mimics can effectively regulate SNARE protein function and accelerate membrane fusion.
• DNA-lipid tethers provide a versatile and programmable platform for synthetic biology applications.
• This approach offers a novel strategy for controlling membrane dynamics and protein interactions.