Nonuniversal impact of cholesterol on membranes mobility, curvature sensing and elasticity

• Published in: Nature communications Vol. 14; no. 1; p. 8038
• Main Authors: Pöhnl, Matthias, Trollmann, Marius F. W., Böckmann, Rainer A.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 11.12.2023; Nature Publishing Group; Nature Portfolio
• Subjects: 119/118; 631/57/2266; 631/57/2270; 639/766/747; Biological membranes; Cholesterol; Elasticity; Humanities and Social Sciences; Lipid membranes; Lipids; Membranes; Mobility; Molecular interactions; multidisciplinary; Phospholipids; Protein interaction; Rigidity; Science; Science (multidisciplinary)
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-023-43892-x

Biological membranes, composed mainly of phospholipids and cholesterol, play a vital role as cellular barriers. They undergo localized reshaping in response to environmental cues and protein interactions, with the energetics of deformations crucial for exerting biological functions. This study investigates the non-universal role of cholesterol on the structure and elasticity of saturated and unsaturated lipid membranes. Our study uncovers a highly cooperative relationship between thermal membrane bending and local cholesterol redistribution, with cholesterol showing a strong preference for the compressed membrane leaflet. Remarkably, in unsaturated membranes, increased cholesterol mobility enhances cooperativity, resulting in membrane softening despite membrane thickening and lipid compression caused by cholesterol. These findings elucidate the intricate interplay between thermodynamic forces and local molecular interactions that govern collective properties of membranes. Cholesterol both thickens and condenses membranes, yet it also softens them under certain conditions. Here, authors uncover cholesterol’s dual role in the delicate balance of rigidity and flexibility in membranes, crucial for diverse biological functions.