Transmembrane proteins with unknown function (TMEMs) as ion channels: electrophysiological properties, structure, and
1Center for Cognition and Sociality, Life Science Cluster, Institute for Basic Science (IBS), 55 Expo-ro, Yuseong-gu, Daejeon, 34126, Republic of Korea.
Experimental & Molecular Medicine
|March 31, 2024
Summary
Transmembrane proteins (TMEM) are increasingly recognized as crucial ion channels. This review summarizes their electrophysiological properties, structural features, and roles in various physiological and pathophysiological processes.
Area of Science:
- Membrane biology
- Ion channel physiology
- Molecular genetics
Background:
- Transmembrane proteins (TMEM) are membrane-spanning proteins with diverse cellular locations.
- Recent discoveries reveal TMEM proteins function as critical ion channels.
- TMEM16A (ANO1) was an early example, initiating extensive research.
Purpose of the Study:
- To review the electrophysiological properties of known TMEM ion channels.
- To compare the structural features of TMEM channels with other ion channels.
- To discuss the physiological and pathophysiological roles of TMEM ion channels.
Main Methods:
- Literature review and synthesis of existing research on TMEM proteins.
- Analysis of electrophysiological data and structural characteristics.
- Compilation of evidence for physiological and pathophysiological functions.
Main Results:
- Summarized electrophysiological properties of TMEM175 (KEL), TMEM206 (PAC), TMEM38 (TRIC), TMEM87A (GolpHCat), TMEM120A (TACAN), TMEM63 (OSCA), TMEM150C (Tentonin3), and TMEM43 (Gapjinc).
- Highlighted unique structural aspects of TMEM ion channels.
- Detailed diverse roles in cellular pH and ion regulation, memory, migration, differentiation, and pain.
Conclusions:
- TMEM proteins represent a significant family of ion channels with broad physiological importance.
- These channels are implicated in various diseases, including Parkinson's, cancer, and cardiovascular disorders.
- Further research into TMEM channels offers potential for novel therapeutic strategies for channelopathies.
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