Mechanistic basis for low threshold mechanosensitivity in voltage-dependent K+ channels
Daniel Schmidt1, Josefina del Mármol, Roderick MacKinnon
1Howard Hughes Medical Institute, Laboratory of Molecular Neurobiology and Biophysics, Rockefeller University, 1230 York Avenue, New York, NY 10065, USA.
Summary
Voltage-dependent potassium (Kv) channels are sensitive to mechanical forces. This study shows these channels can shift their opening range in response to membrane tension, potentially playing a role in cellular mechanosensation.
Area of Science:
- Cell biology
- Biophysics
- Neuroscience
Background:
- Mechanosensation, the cellular response to mechanical forces, is vital for numerous physiological processes.
- While mechanosensation is widespread, the specific ion channels involved in vertebrate mechanotransduction remain largely unidentified.
- Examples include bacterial responses to osmotic shock, blood flow regulation, touch, and hearing.
Purpose of the Study:
- To investigate the role of voltage-dependent potassium (Kv) channels in cellular mechanosensation.
- To determine if Kv channels exhibit sensitivity to mechanical perturbations of the cell membrane.
Main Methods:
- Electrophysiological recordings were used to measure Kv channel activity.
- The study applied controlled mechanical perturbations to the cell membrane.
Main Results:
- Kv channels demonstrated high sensitivity to physiologically relevant mechanical forces.
- Mechanical tension shifted the voltage range for Kv channel opening and increased maximum open probability.
- The observed mechanosensitivity aligns with a model of membrane tension stabilizing a dilated pore during a late-opening transition.
Conclusions:
- Voltage-dependent potassium (Kv) channels are mechanosensitive.
- Kv channels may play a significant role in vertebrate mechanosensation due to their mechanical sensitivity.
- This finding opens new avenues for understanding how cells sense and respond to mechanical stimuli.
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