Figure 1: Schematic diagram showing the diffusion of an nAChR molecule in the plane of the membrane, as followed with the stochastic optical reconstruction microscopy single-molecule localization superresolution microscopy technique. An acetylcholine receptor (red dot) trajectory (black line) is shown to undergo alternating free-walk steps and sojourns of relative immobilization, i.e., a two-state switching behavior combining free Brownian walks and confinement. The latter transient stop-overs occur in nanometer-sized domains (~34 nm radius) with average lifetimes of ~400 ms within zones of high obstacle density (purple colored circles) where several nAChR are clustered, forming pickets that hinder diffusion of their own species. Furthermore, nAChR molecules are transiently trapped and immobilized in larger areas (~150–220 nm radius, green circle) for longer periods of 11 ± 1 seconds, which are affected by the cholesterol content of the membrane. The actin sub-membrane meshwork constitutes an additional source of hindrance to the lateral mobility of the receptors. Adapted from Mosqueira et al., 2018, 2020. nAChR: Nicotinic acetylcholine receptor.