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Engineering and characterization of an enhanced fluorescent protein voltage sensor.

ABSTRACT: BACKGROUND: Fluorescent proteins have been used to generate a variety of biosensors to optically monitor biological phenomena in living cells. Among this class of genetically encoded biosensors, reporters for membrane potential have been a particular challenge. The use of presently known voltage sensor proteins is limited by incorrect subcellular localization and small or absent voltage responses in mammalian cells. RESULTS: Here we report on a fluorescent protein voltage sensor with superior targeting to the mammalian plasma membrane and high responsiveness to membrane potential signaling in excitable cells. CONCLUSIONS AND SIGNIFICANCE: This biosensor, which we termed VSFP2.1, is likely to lead to new methods of monitoring electrically active cells with cell type specificity, non-invasively and in large numbers, simultaneously.

SUBMITTER: Dimitrov D

PROVIDER: S-EPMC1857823 | biostudies-other | 2007

REPOSITORIES: biostudies-other

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Engineering and characterization of an enhanced fluorescent protein voltage sensor.

Dimitrov Dimitar D He You Y Mutoh Hiroki H Baker Bradley J BJ Cohen Lawrence L Akemann Walther W Knöpfel Thomas T

PloS one 20070509 5

<h4>Background</h4>Fluorescent proteins have been used to generate a variety of biosensors to optically monitor biological phenomena in living cells. Among this class of genetically encoded biosensors, reporters for membrane potential have been a particular challenge. The use of presently known voltage sensor proteins is limited by incorrect subcellular localization and small or absent voltage responses in mammalian cells.<h4>Results</h4>Here we report on a fluorescent protein voltage sensor wit ...[more]

PMID: 17487283

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