Ubiquitin C-terminal hydrolase L1 (UCHL1)

Ubiquitin C-terminal hydrolase L1 (UCHL1) is a deubiquitinating enzyme (DUB) and a thiol protease that plays a crucial role in the ubiquitin-proteasome system. It primarily functions by hydrolyzing small C-terminal adducts of ubiquitin, thereby generating and maintaining a stable pool of monoubiquitin, which is essential for protein degradation and cellular homeostasis. UCHL1 is highly expressed in neurons and is involved in critical biological processes such as maintaining synaptic function, regulating inflammatory responses, and modulating oxidative activity. Dysregulation of UCHL1 is implicated in a wide range of diseases, including neurodegenerative disorders like Parkinson's and Alzheimer's disease, traumatic brain injury, and various cancers such as lung, breast, and neuroendocrine carcinomas. In cancer, UCHL1 can act as an oncogene, promoting tumor growth and metastasis by stabilizing key proteins. Consequently, UCHL1 is considered a promising therapeutic target, with inhibitors like LDN-57444 and IMP-1710 being developed to modulate its activity. Furthermore, UCHL1 serves as a valuable biomarker for diagnosing and monitoring conditions like traumatic brain injury and neuroendocrine carcinomas. However, therapeutic targeting presents challenges due to potential off-target effects of inhibitors and the complex, sometimes dual, role of UCHL1 in disease pathogenesis.

Other names

UCH-L1HEL-117NDGOAPARK5PGP 9.5PGP9.5PGP95Uch-L1HEL-S-53ubiquitin C-terminal hydrolase L1SPG79UCHL-1MSY1neuron cytoplastic protein 9.5ubiquitin carboxyl-terminal esterase L1 (ubiquitin thiolesterase)ubiquitin thiolesteraseUBL1UCHL1_HUMANUbiquitin carboxyl-terminal hydrolase isozyme L1Neuron cytoplasmic protein 9.5Ubiquitin thioesterase L1epididymis luminal protein 117epididymis secretory protein Li 53

Inhibitors of Ubiquitin C-terminal hydrolase L1 primarily function by blocking its deubiquitinase activity, which prevents the hydrolysis of ubiquitin C-terminal adducts and the recycling of ubiquitin monomers. This can lead to the accumulation of ubiquitinated proteins or a reduction in the available pool of free ubiquitin, thereby disrupting the ubiquitin-proteasome system. In some cancer contexts, UCHL1 inhibitors can prevent the stabilization of oncogenic transcription factors like Twist1 by allowing their degradation.