Giant organelle vesicles to uncover intracellular membrane mechanics and plasticity

• Published in: Nature communications Vol. 15; no. 1; pp. 3767 - 12
• Main Authors: Santinho, Alexandre, Carpentier, Maxime, Lopes Sampaio, Julio, Omrane, Mohyeddine, Thiam, Abdou Rachid
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 04-05-2024; Nature Publishing Group; Nature Portfolio
• Subjects: 631/1647/2204; 631/57/2270; 631/80/642; Animals; Biophysics; Cell Membrane - metabolism; Chlorocebus aethiops; COS Cells; Endoplasmic reticulum; Endoplasmic Reticulum - metabolism; Endosomes; Humanities and Social Sciences; Humans; Intracellular Membranes - metabolism; Life Sciences; Lipid Droplets - metabolism; Lipids; Lysosomes; Lysosomes - metabolism; Mechanical properties; Membrane vesicles; Membranes; Micromanipulation; Mitochondria; Mitochondria - metabolism; multidisciplinary; Organelles; Organelles - metabolism; Science; Science (multidisciplinary); Triglycerides; Triglycerides - metabolism; Vesicles; Biophysical methods; Organelles; Membrane biophysics
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-024-48086-7

Tools for accessing and studying organelles remain underdeveloped. Here, we present a method by which giant organelle vesicles (GOVs) are generated by submitting cells to a hypotonic medium followed by plasma membrane breakage. By this means, GOVs ranging from 3 to over 10 µm become available for micromanipulation. GOVs are made from organelles such as the endoplasmic reticulum, endosomes, lysosomes and mitochondria, or in contact with one another such as giant mitochondria-associated ER membrane vesicles. We measure the mechanical properties of each organelle-derived GOV and find that they have distinct properties. In GOVs procured from Cos7 cells, for example, bending rigidities tend to increase from the endoplasmic reticulum to the plasma membrane. We also found that the mechanical properties of giant endoplasmic reticulum vesicles (GERVs) vary depending on their interactions with other organelles or the metabolic state of the cell. Lastly, we demonstrate GERVs’ biochemical activity through their capacity to synthesize triglycerides and assemble lipid droplets. These findings underscore the potential of GOVs as valuable tools for studying the biophysics and biology of organelles.
The biophysical properties of cellular organelles are difficult to study directly. Here, the authors generate and characterize osmotically-expanded giant vesicles of several organelles, which maintain some of their functional properties.