Soft Condensed Matter Physics in Molecular and Cell Biology

Living cells are crowded with all the objects that are typically studied by soft matter physicists: polymer chains (e.g. DNA) and networks (e.g. the cytoskeleton), colloids (e.g. globular proteins) ­ all compartmentalized by liquid membranes. Not surprisingly many members of the “soft-matter” community have shifted their research towards more biologically motivated problems. Biophysics, however, goes far beyond classical soft-matter physics presenting many new challenges. A given macromolecule has to be understood as being a part of a living cell, interacting with many other molecules, usually under non-equilibrium conditions. Which components in the cell interact, how does information flow through the cell and how does a cell organise as a whole? Typically one has to start from concrete systems hoping to identify at the end common principles underlying the workings of a cell. Of course, this is only possible in a strongly interdisciplinary approach. It is hence important to bring together experimentalists and theorists on junior and senior level with different backgrounds ranging from biology to physics and mathematics.

This is precisely the goal of the present workshop. We aim at a balanced composition of participants and will focus on five key subjects, one per day. Due to many cross connections between these subjects, we expect strong synergetic effects. Specifically, the subjects are: “From DNA to chromatin”: Eucaryotic DNA is hierarchically folded into a dense nucleo-protein complex called chromatin. Currently physical mechanisms are unravelled through which the cell can gain access to genetic material. “Role of molecular dynamics in protein and nucleic acid function”: It becomes increasingly clear that dynamics in proteins and DNA are important in molecular biology, e.g. in entropic allostery in protein binding to DNA. “Physics of viruses”: Viruses are carrier of genetic material using the cellular machinery of the infected cell to duplicate themselves. Due to their simple building plan they are especially suitable for biophysical studies. “Inhomogeneous (active) biological membranes”: Cell membranes are (inhomogeneous) mixtures of a variety of domains of different lipid species interacting with a plethora of proteins and receptors. Moving on from earlier studies of homogeneous equilibrium membranes, this complex dynamic object is now being studied as far-from-equilibrium soft matter system. “Cellular self organisation”: Many cellular components are now known to assemble themselves in a self-organised fashion. Modelling these non-equilibrium, and often stochastic processes is a major challenge to the biological physics community.