Understanding cell-penetrating peptide mechanisms using computational electrophysiology simulations.

Area of Science:

• Biophysics
• Computational Biology
• Materials Science

Background:

• Cell-penetrating peptides (CPPs) facilitate cellular uptake of cargo molecules like drugs and DNA.
• The precise peptide-membrane interactions governing CPP internalization remain incompletely understood.
• CPPs offer potential for advanced drug and gene delivery systems.

Purpose of the Study:

• To introduce Computational Electrophysiology (CompEL) as a novel tool for studying CPP-membrane interactions.
• To computationally investigate the translocation mechanisms of cationic CPPs (e.g., Arg9, MAP, TP10, TP2).
• To elucidate molecular interactions driving CPP internalization and pore formation.

Main Methods:

• Utilized double bilayer molecular dynamics (MD) simulations.
• Employed CompEL to induce membrane stress via ion imbalance, promoting pore formation.
• Simulated systems with one or eight CPPs to observe translocation and cooperative effects.

Main Results:

• CPPs were observed to translocate across the membrane through induced pores.
• A non-CPP control peptide failed to translocate and instead stabilized the pore.
• Cooperative peptide behavior was noted in systems with multiple CPPs, influencing translocation or pore stabilization.
• CompEL successfully modeled CPP-induced membrane perturbation and translocation.

Conclusions:

• CompEL is a powerful computational tool for CPP research.
• The study provides molecular insights into peptide-membrane interactions governing CPP translocation.
• Findings offer guidance for designing next-generation CPP-based delivery systems.