Biomolecular Function and Activity Modulated by Membranes

The cell, and most organelles, are covered by membranes separating the inside from the outside. As complex mixtures of lipids, proteins, and sugars, biological membranes serve vital functions, such as providing shape and structure, mediating signaling, recognition, selective permeation, etc. Amphipathic lipids, which have polar and non-polar parts, organize into bilayers in polar aqueous environment due to the hydrophobic effect. These bilayers form enclosed compartments providing separate environments for differential enzymatic activity. The membranes also harbor a wide variety of proteins, which transmute a mere barrier to an active surface of massive enzymatic activity in signaling, transport, recognition, etc. Some membranes, like the plasma surrounding the cell, contain sugars at least on one side. Attached to proteins or lipids, they form an additional coating for protection, cell-cell adhesion, etc. Due to their fundamental roles, membranes are not only important drug targets, but also barriers to be circumvented for drug delivery.

Biological membranes have been studied using biophysical and computation methods for a long time. While most studies have considered simple model membranes, recently more and more studies attempt to include the natural complexity of the cellular membranes. Investigating membrane components such as proteins, lipids, and sugars within the complex, interdependent matrix is made possible by the advances in experimental and computational approaches. In this Research Topic, we aim to bring together cutting-edge research highlighting the various levels of complexity biomembranes are investigated at, ranging from studies of individual proteins or lipids in biomembrane function to their complex interactions in membrane structure, transport, and signaling. This Research Topic will also emphasize how different computational simulation and data analyses approaches can be used to investigate biomembranes.

We encourage the submissions covering, but not limited to, the following:

• Membrane transport by proteins and lipids
• Membrane signaling by proteins and lipids
• Intra- and inter-molecular interactions between the membrane components
• The interactions of the membrane with its environment, including membrane cyto-skeleton interactions
• Membrane-membrane interactions: Models and simulations of membrane contact sites
• Complimentary experimental and computational approaches for exploring biomembrane structure and function