Seminar, 23 Feb 2012, M. Gosak

23 February 2012, 16:15
Ernst-Abbe-Platz 2, seminar room 3423

How do topological features of intercellular communication networks characterize the dynamical

Marko Gosak (Department of Physics, Faculty of Natural Sciences and Mathematics, University of Maribor, Slovenia)

New insights gained over the past three decades in the fields of nonlinear dynamics and complex systems are nowadays frequently applied to analyze concrete problems in biology, such as the identification of general principles that underlie the cellular organization and the relation between dynamic behaviors and cellular functions. It is nowadays clear that the functioning of tissues does not only depend on intrinsic rhythms of individual cells, but crucially relies also on collective activity of cell populations. Rhythms essential for life are thus a result of interactions of these cells with each other in terms of intercellular communication. The many efforts devoted to understand collective phenomena in biological systems take now advantage of the recent theory of complex networks. This is definitely related with the fact that complex interaction topologies such as constituted by small-world or scale-free networks have been identified in a plethora of real-life systems, including intercellular communication networks. However, the question arises which network topology ensures the optimal dynamical responses under given circumstances. Namely, cells in different parts of the body have different intrinsic properties and they exhibit diverse temporal patterns. In order to address this issue a mathematical model of the cellular network is employed in which the topology can smoothly be changed from a scale-free network with dominating long-range connections to a homogeneous network with dominating short-range connections, where actually only adjacent cells are connected. This enables the identification of the optimal intercellular network topology leading to the most coherent global response, a desirable attribute of several biological systems, which assures physiological tissue homeostasis. Different examples of cellular dynamics will be discussed with emphasis on neuronal dynamics.