Obstacles Regulate Membrane Tension Propagation to Enable Localized Mechanotransduction.

Area of Science:

• Cellular Biophysics
• Neuroscience
• Mechanotransduction

Background:

• Cellular membranes experience tension gradients from applied forces.
• Understanding membrane tension propagation is key to cellular adaptation.
• Regulation and cell-type dependence of tension propagation remain unclear.

Purpose of the Study:

• Investigate plasma membrane tension propagation in Caenorhabditis elegans mechanosensory neurons.
• Determine factors regulating tension propagation distance and speed.
• Elucidate the role of cytoskeleton and membrane lipids in tension propagation.

Main Methods:

• Experimental observation of tension propagation in C. elegans neurons.
• Biophysical modeling of tension propagation dynamics.
• Perturbation of cytoskeletal elements (actin, microtubules) and lipid properties.

Main Results:

• Tension propagation is rapid and spatially restricted within neuronal neurites.
• Biophysical models indicate periodic obstacle density influences propagation.
• Actin and microtubule cytoskeleton significantly impact tension propagation; lipids have minimal effect.
• The alpha/beta-spectrin network and MEC-2 stomatin condensates act as barriers, limiting tension spread.

Conclusions:

• The cytoskeleton, specifically the spectrin network, plays a critical role in restricting membrane tension propagation.
• Spatial and temporal restriction of tension propagation allows for precise, localized signaling.
• This mechanism enhances neuronal computational capacity by enabling distinct signal processing domains.