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Updated: Aug 11, 2026

Measuring Enzymatic Activity of Neurodevelopmental Disorder-Associated Deubiquitylating Enzymes via an In Vitro Ubiquitin Chain Cleavage Assay
Published on: September 27, 2024
Analysis of Nedd8-associated polypeptides: a model for deciphering the pathway for ubiquitin-like modifications
Jessica A Norman1, Ramin Shiekhattar
1Department of Cell and Molecular Biology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104, USA.
Abstract:
Ubiquitin-like proteins modify target proteins, altering their activities or causing them to be slated for degradation. These modifications are used to efficiently regulate key events in the cell. To explore the set of proteins modified by a small ubiquitin-like protein, we have developed a proteomic approach. Affinity purification of an epitope-tagged Nedd8 allowed the identification of the majority of proteins known to be involved with the neddylation pathway. This purification not only isolated the known targets of neddylation but also the constellation of enzymes and complexes known to regulate neddylation and deneddylation, including the COP9 signalosome, Nub1, and enzymes in the neddylation cascade. This purification scheme can be applied to other small ubiquitin-like proteins, especially those with limited protein targets such as the SUMOs (1, 2, and 3), Isg15, or FAT10.
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