Artificial Nuclear Pore Complexes with Exceptionally Selective Shuttle-Cargo Transport

Area of Science:

• Biophysics
• Materials Science
• Synthetic Biology

Background:

• The nuclear pore complex (NPC) regulates molecular transport between the nucleus and cytoplasm in eukaryotic cells.
• Artificial systems are being developed to mimic NPC transport for fundamental understanding and applications.
• Achieving selective and efficient shuttle-cargo transport in synthetic systems remains a challenge.

Purpose of the Study:

• To develop fully artificial NPCs using polymer complexation.
• To demonstrate efficient and selective transport of cargo molecules through synthetic nanopores.
• To explore potential applications of pH-switchable nanopore systems.

Main Methods:

• Fabrication of polymer brushes (poly(hydroxyethyl acrylamide)) on solid-state nanopores.
• Utilizing pH-dependent multivalent interactions with poly(methacrylic acid) for shuttle-cargo transport.
• Conjugating DNA cargo strands to polymer shuttles for translocation experiments.

Main Results:

• Artificial NPCs demonstrated efficient transport of polymer shuttles through the brush barrier (>1000 molecules per pore per second).
• DNA cargo conjugated to polymer shuttles successfully translocated the nanopores, while free DNA could not.
• Exceptional selectivity was observed, with no detectable leakage of unconjugated macromolecules.

Conclusions:

• Heteromolecular polymer complexation provides a viable strategy for constructing functional artificial NPCs.
• The developed system exhibits high selectivity and pH-switchable transport, mimicking biological transport mechanisms.
• These artificial NPCs offer potential for advanced applications in molecular trapping and nanotechnology.