Abstract: PO1230
Interaction/Modulation of PKD2 by TACAN
Session Information
- Cystic Kidney Disease - I
November 04, 2021 | Location: On-Demand, Virtual Only
Abstract Time: 10:00 AM - 12:00 PM
Category: Genetic Diseases of the Kidneys
- 1001 Genetic Diseases of the Kidneys: Cystic
Authors
- Liu, Xiong, Membrane Protein Disease Research Group, Department of Physiology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
- Fatehi, Mohammad, Department of Pharmacology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
- Zhang, Rui, National "111" Center for Cellular Regulation and Molecular Pharmaceutics, Hubei University of Technology, Wuhan, Hubei, China
- Tang, Jingfeng, National "111" Center for Cellular Regulation and Molecular Pharmaceutics, Hubei University of Technology, Wuhan, Hubei, China
- Light, Peter E., Department of Pharmacology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
- Chen, Xing-Zhen, Membrane Protein Disease Research Group, Department of Physiology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
Background
TACAN (also named TMEM120A), recently reported as a mechano- and pain-sensing ion channel, is distributed in diverse non-neuronal tissues such as heart, intestine and kidney, which indicates its potential role besides pain sensation. Previous proteomic screenings suggested the presence of an interaction between PKD2 and TACAN. In this study, we investigated the physical and functional interaction between the two proteins.
Methods
We employed mutagenesis, molecular cloning, co-immunoprecipitation, immunofluorescence, biotinylation, two-electrode voltage clamp in Xenopus oocytes to measure whole-cell currents and patch-clamp in Chinese hamster ovary (CHO) cells to measure single-channel currents.
Results
We found that TACAN is co-localized and in complex with PKD2 in primary cilia of different kidney cell lines and oocytes. Using oocyte expression, we found that TACAN inhibits the channel activity of PKD2 gain-of-function mutant F604P. Using CHO cell expression, we found that TACAN inhibits both wild-type PKD2 and mutant F604P through reducing their single-channel conductance and open probability. Co-expression of TACAN significantly enhanced the sensitivity of PKD2 to stretch. Further, our data showed that while the first and last transmembrane domains (TM1 and TM6) of TACAN are involved in interaction with transmembrane domains of PKD2 only the TACAN TM6 is functionally relevant.
Conclusion
Our study revealed inhibition of PKD2 channel activity through physical TACAN-PKD2 complexing and that TACAN, but not PKD2, mediates mechanosensitivity of the channel complex. Whether and how TACAN participates in the pore formation remains to be determined.
Funding
- Government Support – Non-U.S.