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Kv12.1 channels are not sensitive to GqPCR-triggered activation of phospholipase C?.

ABSTRACT: Kv12.1 K+ channels are expressed in several brain areas, but no physiological function could be attributed to these subunits so far. As genetically-modified animal models are not available, identification of native Kv12.1 currents must rely on characterization of distinct channel properties. Recently, it was shown in Xenopus laevis oocytes that Kv12.1 channels were modulated by membrane PI(4,5)P2. However, it is not known whether these channels are also sensitive to physiologically-relevant PI(4,5)P2 dynamics. We thus studied whether Kv12.1 channels were modulated by activation of phospholipase C ? (PLC?) and found that they were insensitive to receptor-triggered depletion of PI(4,5)P2. Thus, Kv12.1 channels add to the growing list of K+ channels that are insensitive to PLC? signaling, although modulated by PI(4,5)P2 in Xenopus laevis oocytes.

SUBMITTER: Dierich M

PROVIDER: S-EPMC6986784 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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Kv12.1 channels are not sensitive to GqPCR-triggered activation of phospholipase Cβ.

Dierich Marlen M Leitner Michael G MG

Channels (Austin, Tex.) 20180101 1

Kv12.1 K+ channels are expressed in several brain areas, but no physiological function could be attributed to these subunits so far. As genetically-modified animal models are not available, identification of native Kv12.1 currents must rely on characterization of distinct channel properties. Recently, it was shown in Xenopus laevis oocytes that Kv12.1 channels were modulated by membrane PI(4,5)P2. However, it is not known whether these chann ...[more]

PMID: 30136882

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