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Selective inhibition of neuronal Ca_v3.3 T-type calcium channels by TAT-based channel peptide.

ABSTRACT: Low-voltage-activated Ca_v3 calcium channels (T-type) play an essential role in the functioning of the nervous system where they support oscillatory activities that relie on several channel molecular determinants that shape their unique gating properties. In a previous study, we documented the important role of the carboxy proximal region in the functioning of Ca_v3.3 channels. Here, we explore the ability of a TAT-based cell penetrating peptide containing this carboxy proximal region (TAT-C3P) to modulate the activity of Ca_v3 channels. We show that chronic application of TAT-C3P on tsA-201 cells expressing Ca_v3 channels selectively inhibits Ca_v3.3 channels without affecting Ca_v3.1 and Ca_v3.2 channels. Therefore, the TAT-C3P peptide described in this study represents a new tool to address the specific physiological role of Ca_v3.3 channels, and to potentially enhance our understanding of Ca_v3.3 in disease.

SUBMITTER: Cmarko L

PROVIDER: S-EPMC7304182 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Selective inhibition of neuronal Cav3.3 T-type calcium channels by TAT-based channel peptide.

Cmarko Leos L Weiss Norbert N

Molecular brain 20200619 1

Low-voltage-activated Cav3 calcium channels (T-type) play an essential role in the functioning of the nervous system where they support oscillatory activities that relie on several channel molecular determinants that shape their unique gating properties. In a previous study, we documented the important role of the carboxy proximal region in the functioning of Cav3.3 channels. Here, we explore the ability of a TAT-based cell penetrating peptide containing this carboxy proxim ...[more]

PMID: 32560664

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