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Development of activity-based probes for cathepsin X.

ABSTRACT: Cathepsin X is a lysosomal cysteine protease that functions as a carboxypeptidase with broad substrate specificity. Cathepsin X was discovered only recently, and its physiological roles are still not well understood. A number of studies suggest that cathepsin X may be involved in a variety of biological processes, including cancer, aging and degenerative conditions of the brain, inflammation, and cellular communication. Here we present the synthesis and characterization of several activity-based probes (ABPs) that target active cathepsin X. These ABPs were used to label cathepsin X in complex lysates, whole cells, and in vivo. Furthermore, we have developed a method for selectively labeling and visualizing active cathepsin X in vitro and in vivo. Overall, the probes developed in this study are valuable tools for the study of cathepsin X function.

SUBMITTER: Paulick MG

PROVIDER: S-EPMC3117957 | biostudies-literature | 2011 Jun

REPOSITORIES: biostudies-literature

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Development of activity-based probes for cathepsin X.

Paulick Margot G MG Bogyo Matthew M

ACS chemical biology 20110228 6

Cathepsin X is a lysosomal cysteine protease that functions as a carboxypeptidase with broad substrate specificity. Cathepsin X was discovered only recently, and its physiological roles are still not well understood. A number of studies suggest that cathepsin X may be involved in a variety of biological processes, including cancer, aging and degenerative conditions of the brain, inflammation, and cellular communication. Here we present the synthesis and characterization of several activity-based ...[more]

PMID: 21322635

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