Engineering a cell-based orthogonal ubiquitin transfer cascade for profiling the substrates of RBR E3 Parkin.

ABSTRACT: The E3 ubiquitin (UB) ligase Parkin utilizes a Ring-Between-Ring (RBR) domain to mediate UB transfer to substrate proteins, and mutations affecting Parkin catalysis promote cancer and are associated with Parkinson's disease. An essential role of Parkin is to initiate mitophagy by ubiquitinating mitochondrial proteins. Still, it is unclear how Parkin carries out other cellular functions, such as the regulation of the cell cycle, metabolism, and the neuronal synapse. Here, we used phage display to engineer the RBR domain of Parkin and assembled an orthogonal ubiquitin transfer (OUT) cascade to profile Parkin substrates in living cells. Guided by the substrate profile from the OUT screen, we verified a panel of Rab GTPases and CDK5 as Parkin substrates. We also showed mitophagy stimulation en

SUBMITTER: Fang S 

PROVIDER: S-EPMC12271601 | biostudies-literature | 2025 Jul

REPOSITORIES: biostudies-literature