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Peptide Targeting of Fluorescein-Based Sensors to Discrete Intracellular Locales.

ABSTRACT: Fluorescein-based sensors are the most widely applied class of zinc probes but display adventitious localization in live cells. We present here a peptide-based localization strategy that affords precision in targeting of fluorescein-based zinc sensors. By appending the zinc-selective, reaction-based probe Zinpyr-1 diacetate (DA-ZP1) to the N-terminus of two different targeting peptides we achieve programmable localization and avoid unwanted sequestration within acidic vesicles. Furthermore, this approach can be generalized to other fluorescein-based sensors. When appended to a mitochondrial targeting peptide, the esterase-activated profluorophore 2',7'-dichlorofluorescein diacetate can be used effectively at concentrations four-times lower than previously reported for analogous, non-acetylated derivatives. These results demonstrate on-resin or in-solution esterification of fluorescein to be an effective strategy to facilitate peptide-based targeting in live cells.

SUBMITTER: Radford RJ

PROVIDER: S-EPMC4264632 | biostudies-literature | 2014 Nov

REPOSITORIES: biostudies-literature

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Peptide Targeting of Fluorescein-Based Sensors to Discrete Intracellular Locales.

Radford Robert J RJ Chyan Wen W Lippard Stephen J SJ

Chemical science 20141101 11

Fluorescein-based sensors are the most widely applied class of zinc probes but display adventitious localization in live cells. We present here a peptide-based localization strategy that affords precision in targeting of fluorescein-based zinc sensors. By appending the zinc-selective, reaction-based probe Zinpyr-1 diacetate (DA-ZP1) to the N-terminus of two different targeting peptides we achieve programmable localization and avoid unwanted sequestration within acidic vesicles. Furthermore, this ...[more]

PMID: 25512838

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