Dataset Information

Potassium channel TASK-5 forms functional heterodimers with TASK-1 and TASK-3 to break its silence.

ABSTRACT: TASK-5 (KCNK15) belongs to the acid-sensitive subfamily of two-pore domain potassium (K_2P) channels, which includes TASK-1 and TASK-3. TASK-5 stands out as K_2P channel for which there is no functional data available, since it was reported in 2001 as non-functional and thus "silent". Here we show that TASK-5 channels are indeed non-functional as homodimers, but are involved in the formation of functional channel complexes with TASK-1 and TASK-3. TASK-5 negatively modulates the surface expression of TASK channels, while the heteromeric TASK-5-containing channel complexes located at the plasma membrane are characterized by changes in single-channel conductance, Gq-coupled receptor-mediated channel inhibition, and sensitivity to TASK modulators. The unique pharmacology of TASK-1/TASK-5 heterodimers, affected by a common polymorphism in KCNK15, needs to be carefully considered in the future development of drugs targeting TASK channels. Our observations provide an access to study TASK-5 at the functional level, particularly in malignant cancers associated with KCNK15.

SUBMITTER: Rinne S

PROVIDER: S-EPMC11364637 | biostudies-literature | 2024 Aug

REPOSITORIES: biostudies-literature

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Potassium channel TASK-5 forms functional heterodimers with TASK-1 and TASK-3 to break its silence.

Rinné Susanne S Schick Florian F Vowinkel Kirsty K Schütte Sven S Krasel Cornelius C Kauferstein Silke S Schäfer Martin K-H MK Kiper Aytug K AK Müller Thomas T Decher Niels N

Nature communications 20240830 1

TASK-5 (KCNK15) belongs to the acid-sensitive subfamily of two-pore domain potassium (K<sub>2P</sub>) channels, which includes TASK-1 and TASK-3. TASK-5 stands out as K<sub>2P</sub> channel for which there is no functional data available, since it was reported in 2001 as non-functional and thus "silent". Here we show that TASK-5 channels are indeed non-functional as homodimers, but are involved in the formation of functional channel complexes with TASK-1 and TASK-3. TASK-5 negatively modulates t ...[more]

PMID: 39215006

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Dataset Information

Potassium channel TASK-5 forms functional heterodimers with TASK-1 and TASK-3 to break its silence.

Publications

Potassium channel TASK-5 forms functional heterodimers with TASK-1 and TASK-3 to break its silence.

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