Cellular sensing of most environmental cues involves receptors that affect a signal-transduction excitable network (STEN), which is coupled to a cytoskeletal excitable network (CEN).  In this work, we monitored the dynamics of intracellular cytoskeleton and signaling transduction molecules in Dictyostelium discoideum plated on various nano-topographies. We show that the mechanism of sensing of nanoridges is fundamentally different. CEN activity occurs preferentially on nanoridges, whereas STEN activity is constrained between nanoridges. In the absence of STEN, waves disappear, but long-lasting F-actin puncta persist along the ridges. When CEN is suppressed, wave propagation is no longer constrained by nanoridges. A computational model reproduces these experimental observations. Our findings indicate that nanotopography is sensed directly by CEN, whereas STEN is only indirectly affected due to a CEN-STEN feedback loop. These results explain why texture sensing is robust, and acts cooperatively with multiple other guidance cues in complex microenvironments.

Microscopic data related to chemically induced dimerization (CID) experiments were collected by the Zeiss LSM780 and Zeiss LSM800 GaAsP single-point laser-scanning microscope at room temperature. Other data in this dataset were collected using PerkinElmer spinning disk microscope (Yokogawa CSU-X1 spinning disk scan head (5000 rpm)) with Hamamatsu EMCCD camera and Velocity analysis software.

Image-J can open all the .tif and .lsm data formats in this data set.