Identification of active deubiquitinases in dendritic cells under unstimulated and activated conditions.

Morgan, H. B.; Villadangos, J. A.; Edgington-Mitchell, L. E.; Mintern, J. D.

doi:10.64898/2026.10.08.757166

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bioRxiv · 10.64898/2026.10.08.757166

Identification of active deubiquitinases in dendritic cells under unstimulated and activated conditions.

Morgan, H. B.·Villadangos, J. A.·Edgington-Mitchell, L. E.·Mintern, J. D.

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Abstract

Ubiquitination is a post-translational modification with well described roles in the regulation of immune cell function, such as dendritic cells (DCs). DCs are crucial initiators and regulators of T cell-mediated immune responses. In this study, we use activity-based probes and proteomics to systematically profile DUBs in a DC line. Using the lysate-based biotin(bio)-Ubiquitin(Ub)-propargylamide(Prg) probe and proteomics, the activity and abundance of deubiquitinases was measured in unstimulated and CpG-stimulated MutuDCs to simulate responses to bacteria. This analysis was complemented with profiling using the cell-permeable DUB activity-based probe IMP-2373. The combined analysis with bio-Ub-Prg and IMP-2373 provided insights into the dynamics of DUB activity and abundance in DCs following stimulation and identified several DUBs for further study.

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Morgan, H. B., Villadangos, J. A., Edgington-Mitchell, L. E., Mintern, J. D.. 2026-10-09. Identification of active deubiquitinases in dendritic cells under unstimulated and activated conditions.. https://doi.org/10.64898/2026.10.08.757166

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