Surprising insights into the roles of membranes and the actin cytoskeleton in cellular tension propagation – congratulations to all authors for successfully implementing a new and elegant assay with the C-Trap!
There was a long-standing dispute in the scientific community about whether the actin cortex facilitates or impedes tension propagation in cells because previous studies had produced conflicting results. Some studies claim that membrane tension rapidly propagates across the cell, other studies report little to no propagation of membrane tension. This discrepancy may have been due to differences in experimental techniques, such as the use of different cell types or mechanical assays.
Measuring membrane tension is challenging because it requires precise manipulation and measurement of mechanical forces on individual tethers, which are small and difficult to control. With the C-Trap this could be resolved by combining optical tweezers for direct measurement of mechanical forces on individual tethers with optogenetics for local endogenous control of cell protrusion.
By using this combination of techniques, the lab of Bustamante was able to directly measure changes in membrane tension in response to mechanical forces generated by actin-driven protrusions. This allowed them to demonstrate that these protrusions generate rapid long-range membrane tension propagation in cells, which provides new insights into how cells respond to external stimuli and adapt to their environment.
Defects in actin-driven protrusions and membrane tension propagation have been implicated in a range of conditions, including cancer metastasis, immune cell function, and neurological disorders. By better understanding these processes at the cellular level, researchers may be able to develop new therapies that target specific aspects of these diseases.
Read the full article recently published in Cell.
