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Light-mediated spatial control via photolabile fluorescently quenched peptide cassettes.

ABSTRACT: Light-regulatable compounds are finding increasing utility as spatial and temporal probes of biological behavior. An independent measure of successful light-induced structural change is possible when alteration (e.g., activation, deactivation, etc.) of the bioprobe can be directly linked to a fluorescent readout. We have identified a series of photolabile fluorescently quenched cassettes that display extraordinarily large fluorescence enhancements upon photolysis. A pair of cassettes has been inserted into mitochondrial localization sequences to assess an organelle-targeted light-mediated release strategy for controlling biological activity. The peptide constructs are readily absorbed by mitochondria and subsequently can be cleaved in a light-dependent fashion as assessed by the predicted changes in absorbance and fluorescence.

SUBMITTER: Lee HM

PROVIDER: S-EPMC2819137 | biostudies-literature | 2010 Feb

REPOSITORIES: biostudies-literature

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Light-mediated spatial control via photolabile fluorescently quenched peptide cassettes.

Lee Hsien-Ming HM Priestman Melanie A MA Lawrence David S DS

Journal of the American Chemical Society 20100201 5

Light-regulatable compounds are finding increasing utility as spatial and temporal probes of biological behavior. An independent measure of successful light-induced structural change is possible when alteration (e.g., activation, deactivation, etc.) of the bioprobe can be directly linked to a fluorescent readout. We have identified a series of photolabile fluorescently quenched cassettes that display extraordinarily large fluorescence enhancements upon photolysis. A pair of cassettes has been in ...[more]

PMID: 20073458

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