An optimized activity-based probe for the study of caspase-6 activation

Laura Edgington-Mitchell, Bram J. Van Raam, Martijn Verdoes, Christoph Wierschem, Guy S. Salvesen, Matthew Bogyo

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44 Citations (Scopus)

Abstract

Although significant efforts have been made to understand the mechanisms of caspase activation during apoptosis, many questions remain regarding how and when executioner caspases get activated. We describe the design and synthesis of an activity-based probe that labels caspase-3/-6/-7, allowing direct monitoring of all executioner caspases simultaneously. This probe has enhanced in vivo properties and reduced cross-reactivity compared to our previously reported probe, AB50. Using this probe, we find that caspase-6 undergoes a conformational change and can bind substrates even in the absence of cleavage of the proenzyme. We also demonstrate that caspase-6 activation does not require active caspase-3/-7, suggesting that it may autoactivate or be cleaved by other proteases. Together, our results suggest that caspase-6 activation proceeds through a unique mechanism that may be important for its diverse biological functions.

Original languageEnglish
Pages (from-to)340-352
Number of pages13
JournalChemistry and Biology
Volume19
Issue number3
DOIs
Publication statusPublished - 23 Mar 2012
Externally publishedYes

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