Cell membranes play a crucial role in maintaining the integrity and functionality of cells. However, the mechanisms by which they perform these roles are not yet fully understood. Scientists from the University of Geneva (UNIGE), in collaboration with the Institut de biologie structurale de Grenoble (IBS) and the University of Fribourg (UNIFR), have used cryo-electron microscopy to observe how lipids and proteins at the plasma membrane interact and react to mechanical stress.
This work shows that, depending on conditions, small membrane regions can stabilize various lipids to trigger specific cellular responses. These discoveries, published in the journal Nature , confirm the existence of well-organized lipid domains and begin to reveal the role they play in cell survival. Cells are surrounded by a membrane - the plasma membrane - which acts as a physical barrier but must also be malleable.
These properties are endowed by the constituent components of membranes - lipids and proteins - whose molecular organization varies according to the external environment. This dynamism is critical to membrane function but must be finely balanced to ensure that the membrane becomes neither too tense nor too floppy. How cells sense changes in the biophysical properties of the plasma membrane is thought to involve microregions on the membrane - known as microdomains - which are postulated to possess a specific lipid and protein content and organization.
High-resolution cryo-electron microscop.