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  • KSBNS 2024

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Short Communication

Exp Neurobiol 2021; 30(5): 319-328

Published online October 31, 2021

https://doi.org/10.5607/en21028

© The Korean Society for Brain and Neural Sciences

A Deafness Associated Protein TMEM43 Interacts with KCNK3 (TASK-1) Two-pore Domain K+ (K2P) Channel in the Cochlea

Minwoo Wendy Jang1,2, Tai Young Kim2, Kushal Sharma3, Jea Kwon1,2, Eunyoung Yi3 and C. Justin Lee1,2*

1KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 02841,
2Center for Cognition and Sociality, Institute for Basic Science (IBS), Daejeon 34141,
3College of Pharmacy and Natural Medicine Research Institute, Mokpo National University, Mokpo 58554, Korea

Correspondence to: *To whom correspondence should be addressed.
TEL: 82-42-878-9150, FAX: 82-42-878-9151
e-mail: cjl@ibs.re.kr

Received: August 14, 2021; Revised: October 12, 2021; Accepted: October 15, 2021

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

The TMEM43 has been studied in human diseases such as arrhythmogenic right ventricular cardiomyopathy type 5 (ARVC5) and auditory neuropathy spectrum disorder (ANSD). In the heart, the p.(Ser358Leu) mutation has been shown to alter intercalated disc protein function and disturb beating rhythms. In the cochlea, the p.(Arg372Ter) mutation has been shown to disrupt connexin-linked function in glia-like supporting cells (GLSs), which maintain inner ear homeostasis for hearing. The TMEM43-p.(Arg372Ter) mutant knock-in mice displayed a significantly reduced passive conductance current in the cochlear GLSs, raising a possibility that TMEM43 is essential for mediating the passive conductance current in GLSs. In the brain, the two-pore-domain potassium (K2P) channels are generally known as the “leak channels” to mediate background conductance current, raising another possibility that K2P channels might contribute to the passive conductance current in GLSs. However, the possible association between TMEM43 and K2P channels has not been investigated yet. In this study, we examined whether TMEM43 physically interacts with one of the K2P channels in the cochlea, KCNK3 (TASK-1). Utilizing co-immunoprecipitation (IP) assay and Duolink proximity ligation assay (PLA), we revealed that TMEM43 and TASK-1 proteins could directly interact. Genetic modifications further delineated that the intracellular loop domain of TMEM43 is responsible for TASK-1 binding. In the end, gene-silencing of Task-1 resulted in significantly reduced passive conductance current in GLSs. Together, our findings demonstrate that TMEM43 and TASK-1 form a protein-protein interaction in the cochlea and provide the possibility that TASK-1 is a potential contributor to the passive conductance current in GLSs.

Graphical Abstract


Keywords: TMEM43, KCNK3, Cochlea, Protein interaction domains and motifs, Ion transport