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bioRxiv · 10.1101/330993

TRPV4 interacts with mitochondrial proteins and acts as a mitochondrial structure-function regulator

Kumar, A.·Majhi, R. K.·Acharya, T. K.·Smalla, K.-H.·Gundelfinger, E. D.·Goswami, C.
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Abstract

TRPV4 has been linked with the development of sensory defects, neuropathic pain, neurodegenerative disorders such as Charcot Marie Tooth disease and various muscular dystrophies. In all these cases mitochondrial abnormalities were tagged as cellular hallmarks and such abnormalities have been reported as key factor for the pathophysiological conditions. Mitochondria also have the unique ability to sense and regulate their own temperature. Here, we demonstrate that TRPV4, a thermosensitive ion channels, localizes to a subpopulation of mitochondria in various cell lines, in primary cells and also in sperm cells. Improper expression and/or function of TRPV4 induce several mitochondrial abnormalities such as low oxidative potential, high Ca2+-influx and changes in electron transport chain functions. TRPV4 is also involved in regulation of mitochondrial morphology, smoothness, and fusion-fission events. The C-terminal cytoplasmic region of TRPV4 can localize it to mitochondria and interacts with mitochondrial proteins including Hsp60, Mfn1 and Mfn2. Regulation of mitochondria by TRPV4 may contribute to previously uncharacterized mitochondria-specific functions observed in various cell types. This discovery may help to link TRPV4-mediated channelopathies with mitochondria-mediated diseases.

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Kumar, A., Majhi, R. K., Acharya, T. K., Smalla, K.-H., Gundelfinger, E. D., Goswami, C.. 2018-05-25. TRPV4 interacts with mitochondrial proteins and acts as a mitochondrial structure-function regulator. https://doi.org/10.1101/330993

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