Cholesterol makes cell membranes flexible and robust

Computer biologists at FAU discover new mechanism

Cholesterol plays a decisive role in the elasticity of cell membranes. Researchers at FAU have now discovered that cholesterol has a remarkable double role: It not only contributes to making the membrane thicker and more impenetrable, but surprisingly also softer. This new discovery, that was published in the journal “Nature Communications”, opens new perspectives for membrane research and potential applications in biotechnology.

Cholesterol is essential for the structure, elasticity and many different functions of cell membranes

Accounting for up to 40 percent of the membrane, cholesterol is essential for the structure, elasticity and the various functions of cell membranes. Cell membranes act as barriers that separate the interior of the cell from its surroundings and regulate the selective transport of material into and out of the cell. “Earlier experiments demonstrated that the main components of the membrane, the lipids, are compressed by cholesterol,” explains Prof. Dr. Rainer Böckmann, head of the Computational Biology working group at the Department of Biology at FAU. “This makes the membrane thicker and less penetrable.”

The effect of cholesterol depends on the lipid composition of the membrane

Using a computer simulation, the researchers discovered that the effect of cholesterol depended on the lipid composition of the membrane: It makes saturated membranes more rigid, but unsaturated membranes more flexible. This leads to a seemingly contradictory situation, in which the membranes simultaneously become thicker and softer. The computer simulations supported by the Center for National High-Performance Computing Erlangen (NHR@FAU) show that this phenomenon can be explained by the increased mobility of cholesterol in unsaturated membranes.

Far-reaching significance for a number of biological processes

This discovery has far-reaching significance for a number of biological processes at the cell membrane. “The study helps us gain a better understanding of how cholesterol influences cell communication and resorption,” explains Rainer Böckmann. Although this is fundamental research, the discovered mechanism could have important implications for biotechnology, in particular in the development of artificial membranes with improved physical properties.

Further information:

Prof. Dr. Rainer Böckmann

Professorship for Computational Chemistry

Phone: +49 9131 85 25409

rainer.boeckmann@fau.de

https://doi.org/10.1038/s41467-023-43892-xhttps://doi.org/10.1038/s41467-023-43892-x