Rapid propagation of membrane tension at retinal bipolar neuron presynaptic terminals

Many cellular activities, such as cell migration, cell division, phagocytosis, and exo-endocytosis, generate and are regulated by membrane tension gradients. Membrane tension gradients drive membrane flows, but there is controversy over how rapidly plasma membrane flow can relax tension gradients. Here, we show that membrane tension can propagate rapidly or slowly, spanning orders of magnitude in speed, depending on the cell type. In a neuronal terminal specialized for rapid synaptic vesicle turnover, membrane tension equilibrates within seconds. By contrast, membrane tension does not propagate in neuroendocrine adrenal chromaffin cells secreting catecholamines. Stimulation of exocytosis causes a rapid, global decrease in the synaptic terminal membrane tension, which recovers slowly due to endocytosis. Thus, membrane flow and tension equilibration may be adapted to distinct membrane recycling requirements.

Automated summary

Membrane tension gradients play a crucial role in cellular activities such as cell migration, division, phagocytosis, and exo-endocytosis. The speed at which membrane tension equilibrates can vary significantly depending on the cell type. Rapid synaptic vesicle turnover in neuronal terminals leads to quick membrane tension equilibration, while neuroendocrine adrenal chromaffin cells have slower recovery rates.