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bioRxiv · 10.1101/775627

The Activome: multiplexed probing of activity of proteolytic enzymes using mass cytometry-compatible activity-based probes (TOF-probes)

Poreba, M.·Groborz, K.·Rut, W.·Pore, M.·Snipas, S. J.·Vizovisek, M.·Turk, B.·Drag, M.·Salvesen, G. S.
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Abstract

The activome can be considered as a subset of the proteome that contains enzymes in their catalytically active form and can be interrogated by using probes targeted towards individual specific enzymes. A subset of such enzymes are proteases that are frequently studied with activity-based probes, small inhibitors equipped with a detectable tag, commonly a fluorophore. Due to the spectral overlap of these commonly used fluorophores, simultaneous analysis becomes limited. To overcome this, we developed a series of protease-selective lanthanide-labeled probes compatible with mass cytometry. Using lanthanide-based tags instead of fluorophores gives us the ability to monitor the activity of multiple proteases in parallel. As proof of concept we developed a panel of cathepsin and legumain specific probes and showed that we were able to identify an activome of these proteases in two cell lines and peripheral blood mononuclear cells, providing a framework for the use of mass cytometry for multiplexed enzyme activity detection.

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Poreba, M., Groborz, K., Rut, W., Pore, M., Snipas, S. J., Vizovisek, M., Turk, B., Drag, M., Salvesen, G. S.. 2019-09-23. The Activome: multiplexed probing of activity of proteolytic enzymes using mass cytometry-compatible activity-based probes (TOF-probes). https://doi.org/10.1101/775627

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