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Fluorogenic Substrates for In Situ Monitoring of Caspase-3 Activity in Live Cells.

ABSTRACT: The in situ detection of caspase-3 activity has applications in the imaging and monitoring of multiple pathologies, notably cancer. A series of cell penetrating FRET-based fluorogenic substrates were designed and synthesised for the detection of caspase-3 in live cells. A variety of modifications of the classical caspase-3 and caspase-7 substrate sequence Asp-Glu-Val-Asp were carried out in order to increase caspase-3 affinity and eliminate caspase-7 cross-reactivity. To allow cellular uptake and good solubility, the substrates were conjugated to a cationic peptoid. The most selective fluorogenic substrate 27, FAM-Ahx-Asp-Leu-Pro-Asp-Lys(MR)-Ahx, conjugated to the cell penetrating peptoid at the C-terminus, was able to detect and quantify caspase-3 activity in apoptotic cells without cross-reactivity by caspase-7.

SUBMITTER: Perez-Lopez AM

PROVIDER: S-EPMC4864350 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature

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Fluorogenic Substrates for In Situ Monitoring of Caspase-3 Activity in Live Cells.

Pérez-López Ana M AM Soria-Gila M Lourdes ML Marsden Emma R ER Lilienkampf Annamaria A Bradley Mark M

PloS one 20160511 5

The in situ detection of caspase-3 activity has applications in the imaging and monitoring of multiple pathologies, notably cancer. A series of cell penetrating FRET-based fluorogenic substrates were designed and synthesised for the detection of caspase-3 in live cells. A variety of modifications of the classical caspase-3 and caspase-7 substrate sequence Asp-Glu-Val-Asp were carried out in order to increase caspase-3 affinity and eliminate caspase-7 cross-reactivity. To allow cellular uptake an ...[more]

PMID: 27168077

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