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C2-domain mediated nano-cluster formation increases calcium signaling efficiency.

ABSTRACT: Conventional protein kinase Cs (cPKCs) are key signaling proteins for transducing intracellular Ca²⁺ signals into downstream phosphorylation events. However, the lifetime of individual membrane-bound activated cPKCs is an order of magnitude shorter than the average time needed for target-protein phosphorylation. Here, we employed intermolecular Förster resonance energy transfer (FRET) in living cells combined with computational analysis to study the spatial organization of cPKCs bound to the plasma membrane. We discovered Ca²⁺-dependent cPKC nano-clusters that significantly extend cPKC's plasma-membrane residence time. These protein patterns resulted from self-assembly mediated by Ca²⁺-binding C2-domains, which are widely used for membrane-targeting of Ca²⁺-sensing proteins. We also established clustering of other unrelated C2-domain containing proteins, suggesting that nano-cluster formation is a key step for efficient cellular Ca²⁺-signaling.

SUBMITTER: Bonny M

PROVIDER: S-EPMC5093555 | biostudies-literature | 2016 Nov

REPOSITORIES: biostudies-literature

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C2-domain mediated nano-cluster formation increases calcium signaling efficiency.

Bonny Mike M Hui Xin X Schweizer Julia J Kaestner Lars L Zeug André A Kruse Karsten K Lipp Peter P

Scientific reports 20161103

Conventional protein kinase Cs (cPKCs) are key signaling proteins for transducing intracellular Ca<sup>2+</sup> signals into downstream phosphorylation events. However, the lifetime of individual membrane-bound activated cPKCs is an order of magnitude shorter than the average time needed for target-protein phosphorylation. Here, we employed intermolecular Förster resonance energy transfer (FRET) in living cells combined with computational analysis to study the spatial organization of cPKCs bound ...[more]

PMID: 27808106

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