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A T-type channel-calmodulin complex triggers ?CaMKII activation.

ABSTRACT: Calmodulin (CaM) is an important signaling molecule that regulates a vast array of cellular functions by activating second messengers involved in cell function and plasticity. Low voltage-activated calcium channels of the Cav3 family have the important role of mediating low threshold calcium influx, but were not believed to interact with CaM. We find a constitutive association between CaM and the Cav3.1 channel at rest that is lost through an activity-dependent and Cav3.1 calcium-dependent CaM dissociation. Moreover, Cav3 calcium influx is sufficient to activate ?CaMKII in the cytoplasm in a manner that depends on an intact Cav3.1 C-terminus needed to support the CaM interaction. Our findings thus establish that T-type channel calcium influx invokes a novel dynamic interaction between CaM and Cav3.1 channels to trigger a signaling cascade that leads to ?CaMKII activation.

SUBMITTER: Asmara H

PROVIDER: S-EPMC5553682 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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A T-type channel-calmodulin complex triggers αCaMKII activation.

Asmara Hadhimulya H Micu Ileana I Rizwan Arsalan P AP Sahu Giriraj G Simms Brett A BA Zhang Fang-Xiong FX Engbers Jordan D T JDT Stys Peter K PK Zamponi Gerald W GW Turner Ray W RW

Molecular brain 20170811 1

Calmodulin (CaM) is an important signaling molecule that regulates a vast array of cellular functions by activating second messengers involved in cell function and plasticity. Low voltage-activated calcium channels of the Cav3 family have the important role of mediating low threshold calcium influx, but were not believed to interact with CaM. We find a constitutive association between CaM and the Cav3.1 channel at rest that is lost through an activity-dependent and Cav3.1 calcium-dependent CaM d ...[more]

PMID: 28800734

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