Physical interactions control information transfer at living interfaces

Living interfaces process and relay information across compartment boundaries to regulate biological functions. For example, cells sense and respond to mechanical changes in their environment through processes at their surface. We ask how physical interactions at biological interfaces affect their capacity to process information. Starting from a statistical description of surface-associated particles with short-range repulsion, we combine numerical and analytical approaches to describe how stochastic binding to a structure in the environment affects the particle distribution. We find nonlinear mappings, which act as thresholding filters, between input binding energy heterogeneities and steady-state particle distributions and discuss how this mechanism can constitute a form of proximity sensing between adjacent structures. Focussing on how particle and domain properties control which input features are transmitted by the filter, we obtain a parameter region for effective information transmission. We compare this to a diverse range of surface-associated protein complexes and macromolecular structures and discuss which systems may utilize this physical sensing principle. These results suggest a physical mechanism for implementing sensing in synthetic systems.