Designer peptide-DNA cytoskeletons regulate the function of synthetic cells

Area of Science:

• Biomaterials Engineering
• Synthetic Biology
• Cellular Mechanics

Background:

• Artificial cell engineering demands dynamic and reconfigurable cytoskeletal elements.
• Actin-binding proteins inspire strategies for filament organization and mechanical modulation.
• Bottom-up assembly of synthetic cells requires precise control over internal structures.

Purpose of the Study:

• To design and characterize novel peptide-DNA crosslinkers for artificial cell cytoskeleton construction.
• To investigate the influence of crosslinker properties on cytoskeletal organization and mechanical behavior.
• To demonstrate the utility of tunable cytoskeletal structures for payload regulation within synthetic cells.

Main Methods:

• Designed a library of peptide-DNA crosslinkers with varied length, valency, and geometry.
• Formed tactoid-shaped peptide filament bundles via DNA hybridization.
• Confined peptide-DNA structures within cell-sized water-in-oil droplets.
• Investigated payload diffusion and recruitment/release mechanisms using complementary DNA handles.
• Utilized heat-induced DNA melting to trigger droplet shape deformations.

Main Results:

• Peptide-DNA crosslinkers formed tactoid bundles with tunable aspect ratios and mechanics.
• Cytoskeletal structures localized to the cortex or lumen of synthetic cells based on DNA crosslinker design.
• Tunable spatial arrangement regulated passive payload diffusion.
• Reversible payload recruitment and release were achieved via DNA hybridization.
• Heat-induced reconfiguration led to controllable droplet shape changes.

Conclusions:

• Modular peptide-DNA architectures provide a versatile platform for bottom-up synthetic cell assembly.
• The designed crosslinkers enable precise control over cytoskeletal organization, mechanics, and payload interactions.
• This approach advances the development of functional synthetic cells with dynamic internal organization.