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Regulation of Cardiac Cav1.2 Channels by Calmodulin.

ABSTRACT: Cav1.2 Ca²⁺ channels, a type of voltage-gated L-type Ca²⁺ channel, are ubiquitously expressed, and the predominant Ca²⁺ channel type, in working cardiac myocytes. Cav1.2 channels are regulated by the direct interactions with calmodulin (CaM), a Ca²⁺-binding protein that causes Ca²⁺-dependent facilitation (CDF) and inactivation (CDI). Ca²⁺-free CaM (apoCaM) also contributes to the regulation of Cav1.2 channels. Furthermore, CaM indirectly affects channel activity by activating CaM-dependent enzymes, such as CaM-dependent protein kinase II and calcineurin (a CaM-dependent protein phosphatase). In this article, we review the recent progress in identifying the role of apoCaM in the channel 'rundown' phenomena and related repriming of channels, and CDF, as well as the role of Ca²⁺/CaM in CDI. In addition, the role of CaM in channel clustering is reviewed.

SUBMITTER: Kameyama M

PROVIDER: S-EPMC10094977 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature

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Regulation of Cardiac Cav1.2 Channels by Calmodulin.

Kameyama Masaki M Minobe Etsuko E Shao Dongxue D Xu Jianjun J Gao Qinghua Q Hao Liying L

International journal of molecular sciences 20230329 7

Cav1.2 Ca2+ channels, a type of voltage-gated L-type Ca2+ channel, are ubiquitously expressed, and the predominant Ca2+ channel type, in working cardiac myocytes. Cav1.2 channels are regulated by the direct interactions with calmodulin (CaM), a Ca2+-binding protein that causes Ca2+-dependent facilitation (CDF) and inactivation (CDI). Ca2+-free CaM (apoCaM) also contributes to the regulation of Cav1.2 channels. Furthermore, CaM ind ...[more]

PMID: 37047381

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