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Neuronal Calcium Recording with an Engineered TEV Protease.

ABSTRACT: Technologies for measuring the transient Ca2+ spikes that accompany neural signaling have revolutionized our understanding of the brain. Nevertheless, microscopic visualization of Ca2+ spikes on the time scale of neural activity across large brain regions or in thick specimens remains a significant challenge. The recent development of stable integrators of Ca2+, instead of transient reporters, provides an avenue to investigate neural signaling in otherwise challenging systems. Here, we describe an engineered Ca2+-sensing enzyme consisting of a split Tobacco Etch Virus (TEV) protease with each half tethered to a calmodulin or M13 Ca2+ binding domain. This Split TEV, Ca2+ Activated Neuron Recorder (SCANR) remains separate and catalytically incompetent until a spike in cellular Ca2+ triggers its reconstitution and the subsequent turnover of a caged, genetically encoded reporter substrate. We report the identification of a successful Ca2+-sensing split TEV from a library of chimeras and deployment of the enzyme in primary rat hippocampal neurons.

SUBMITTER: O'Neill BK

PROVIDER: S-EPMC6905437 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature

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Neuronal Calcium Recording with an Engineered TEV Protease.

O'Neill Brianna K BK Laughlin Scott T ST

ACS chemical biology 20180502 5

Technologies for measuring the transient Ca2+ spikes that accompany neural signaling have revolutionized our understanding of the brain. Nevertheless, microscopic visualization of Ca2+ spikes on the time scale of neural activity across large brain regions or in thick specimens remains a significant challenge. The recent development of stable integrators of Ca2+, instead of transient reporters, provides an avenue to investigate neural signaling in otherwise challe ...[more]

PMID: 29701954

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