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A photoactivatable push-pull fluorophore for single-molecule imaging in live cells.

ABSTRACT: We have reengineered a red-emitting dicyanomethylenedihydrofuran push-pull fluorophore so that it is dark until photoactivated with a short burst of low-intensity violet light. Photoactivation of the dark fluorogen leads to conversion of an azide to an amine, which shifts the absorption to long wavelengths. After photoactivation, the fluorophore is bright and photostable enough to be imaged on the single-molecule level in living cells. This proof-of-principle demonstration provides a new class of bright photoactivatable fluorophores, as are needed for super-resolution imaging schemes that require active control of single molecule emission.

SUBMITTER: Lord SJ

PROVIDER: S-EPMC2688641 | biostudies-literature | 2008 Jul

REPOSITORIES: biostudies-literature

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A photoactivatable push-pull fluorophore for single-molecule imaging in live cells.

Lord Samuel J SJ Conley Nicholas R NR Lee Hsiao-lu D HL Samuel Reichel R Liu Na N Twieg Robert J RJ Moerner W E WE

Journal of the American Chemical Society 20080624 29

We have reengineered a red-emitting dicyanomethylenedihydrofuran push-pull fluorophore so that it is dark until photoactivated with a short burst of low-intensity violet light. Photoactivation of the dark fluorogen leads to conversion of an azide to an amine, which shifts the absorption to long wavelengths. After photoactivation, the fluorophore is bright and photostable enough to be imaged on the single-molecule level in living cells. This proof-of-principle demonstration provides a new class o ...[more]

PMID: 18572940

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