Self-Assembled Rough Endoplasmic Reticulum-Like Proto-Organelles

Area of Science:

• Biomimetic materials science
• Cell biology
• Membrane biophysics

Background:

• Organelle morphology is crucial for cellular function, with cisternae stacks being a universal structure.
• Mimicking spherical organelles is established, but creating cisternal organelle-like structures remains challenging.
• The rough endoplasmic reticulum (RER) features a crowded, confined environment within its cisternae.

Purpose of the Study:

• To assemble RER-like helicoidal cisternae stacks as advanced membrane models.
• To investigate the role of membrane electrostatics in the formation and shaping of these structures.
• To create a biomimetic system that can modulate enzyme environments for biochemical reactions.

Main Methods:

• Fabrication of helicoidal cisternae stacks mimicking RER structure.
• Analysis of different helicoid formations (single, multiple, secondary).
• Investigation of membrane electrostatics as a driving force for structure formation.

Main Results:

• Successfully assembled RER-like helicoidal cisternae stacks.
• Observed various helicoid morphologies, including single, multiple, and secondary helices.
• Demonstrated that membrane electrostatics drive the formation and control the proportions of these helicoids, suggesting a role in RER shaping.
• Showcased the reversible expansion and compression of the cisternae stacks, enabling modulated enzyme environments.

Conclusions:

• This study provides novel mechanisms for organelle shaping and helicoid formation.
• The developed membrane models offer new insights into the role of membrane electrostatics in cellular structures.
• These biomimetic cisternae stacks hold significant potential for applications in biomimetics, cell biology, and advanced materials design.