Ubiquitin carboxyl-terminal hydrolase 1 (UCHL1)

Ubiquitin carboxyl-terminal hydrolase 1 (UCHL1) is a deubiquitinating enzyme (DUB) that plays a critical role in the ubiquitin–proteasome system (UPS). It is highly expressed in neurons and cells of the diffuse neuroendocrine system. UCHL1 has hydrolase and ligase activities, maintaining cellular homeostasis by recycling ubiquitin molecules. Mutations or altered expression are implicated in neurodegenerative diseases like Parkinson’s and cancer. It localizes to nucleus, cytoplasm, endoplasmic reticulum, plasma membrane and mitochondria, showing its involvement in multiple aspects of intracellular protein regulation. By cleaving short peptide fragments from the C terminus of ubiquitinated substrates (~10 residues), it increases available monomeric ubiquitin pools necessary for ongoing proteasomal degradation cycles. It also stabilizes other important signaling molecules such as EGFR by preventing their degradation via deubiquitination pathways.

Other names

UCH-L1PGP9.5PARK5Neuron cytoplasmic protein 9.5HEL-117NDGOASPG79

Inhibition of deubiquitinase activity, modulation of ubiquitin levels