Fluorogenic Substrates for In Situ Monitoring of Caspase-3 Activity in Live Cells Pérez-López, Ana M. Soria-Gila, M. Lourdes Marsden, Emma R. Lilienkampf, Annamaria Bradley, Mark Apoptosis Fluorescence imaging Flow cytometry Cross reactivity Peptide synthesis Apoptotic signaling cascade High performance liquid chromatography 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. 2017-02-08T13:44:19Z 2017-02-08T13:44:19Z 2016 info:eu-repo/semantics/article Pérez-López, A.M.; et al. Fluorogenic Substrates for In Situ Monitoring of Caspase-3 Activity in Live Cells. Plos One, 11(5): e0153209 (2016). [http://hdl.handle.net/10481/44744] 1932-6203 http://hdl.handle.net/10481/44744 10.1371/journal.pone.0153209 eng http://creativecommons.org/licenses/by-nc-nd/3.0/ info:eu-repo/semantics/openAccess Creative Commons Attribution-NonCommercial-NoDerivs 3.0 License Public Library of Science (PLOS)