About this Research Topic
Plasma membranes and in general biomembranes establish and maintain differences in composition between the cell or organelle interior and exterior. Biomembranes are the site for cell-cell recognition, they allow active and passive transport of material into and out of the cell, and they harbor proteins as initiators of signal transduction pathways.
This functional variety of biomembranes is intimately coupled to their organelle-specific, asymmetric composition. For example, eukaryotic cells harbor more than 1,000 different lipids varying in their headgroups and aliphatic chains. The composite nature of cell membranes consisting of a lipid bilayer with embedded membrane proteins was first described by the Singer-Nicolson fluid-mosaic model in 1972.
Subsequently, the passive role attributed to lipids in the fluid-mosaic model was expanded to a coupled organization of lipids and proteins in membranes, and the importance of protein-lipid interactions for the proper functioning of transporters and ion channels was recognized. The membrane model was further refined by the inclusion of the glycocalix and the cytoskeleton. The formation of membrane domains, the so-called tightly packed lipid rafts, was suggested to be essential for the coordination of membrane function e.g. in membrane trafficking and signalling.
Despite decades of scientific work on membranes, the onset of which can be traced to the first lipid bilayer model by Gorter and Grendel, many open questions persist regarding the relation of membrane composition, structure, and dynamics to the ability of membranes to laterally segregate and form domains with specific hydrophobic thickness, ordering, and lateral pressure, hence to make the membrane functional.
This Research Topic therefore addresses in particular (i) the mutual interaction of lipids and proteins, (ii) the composition-dependent formation of membrane (micro)domains, and, (iii) the influence of lipids on biological processes.