Related Experiment Video
Updated: Aug 5, 2026
09:59
Utilizing pHluorin-tagged Receptors to Monitor Subcellular Localization and Trafficking
Published on: March 16, 2017
gp91phox regulates Hv1 channel gating and membrane trafficking via direct interaction
Shivani Yadav1, Ashutosh Sharma1, Kunvar Ravendra Singh2
1Neuroscience and Ageing Biology Division, CSIR-Central Drug Research Institute, Lucknow, 226031, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India.
Biochemical and Biophysical Research Communications
|August 1, 2026
Summary
The study reveals that gp91phox, a component of NADPH oxidase (NOX2), directly interacts with and regulates the voltage-gated proton channel (Hv1). This interaction controls Hv1 gating kinetics and membrane expression, uncovering a new mechanism for redox signaling in immune cells.
Area of Science:
- Cellular Biology
- Immunology
- Neuroscience
Background:
- Voltage-gated proton channel (Hv1) and NADPH oxidase (NOX2) are crucial for ROS generation in immune cells.
- The direct regulatory role of NOX2 components on Hv1 channel behavior is not well understood.
Purpose of the Study:
- To investigate the molecular and functional relationship between Hv1 and the NOX2 catalytic subunit gp91phox.
- To elucidate the role of gp91phox in Hv1 channel gating, expression, and trafficking.
Main Methods:
- Co-immunoprecipitation and proximity ligation assays to detect physical interactions.
- Electrophysiology (patch-clamp) to study Hv1 channel kinetics and current density.
- Knockdown and co-expression studies in BV2 microglial and HEK293T cells.
- Cell surface protein biotinylation and trafficking assays.
Main Results:
- A physical interaction between Hv1 and gp91phox was confirmed.
- gp91phox knockdown accelerated Hv1 channel gating kinetics.
- Co-expression of gp91phox with Hv1 restored slow gating kinetics.
- gp91phox deficiency significantly reduced Hv1 current density and membrane expression.
- gp91phox depletion impaired Hv1 membrane trafficking.
Conclusions:
- gp91phox directly regulates Hv1 channel function, including gating kinetics and membrane expression.
- NOX2 components play a novel role in controlling Hv1 channel trafficking beyond electrochemical coupling.
- This identifies a new mechanism coordinating redox signaling and proton channel regulation in microglial cells.
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