USP10 Protein
Overview
USP10 (ubiquitin-specific protease 10) is a deubiquitinating enzyme belonging to the ubiquitin-specific protease (USP) family, a large class of cysteine proteases that remove ubiquitin modifications from target proteins. The USP10 gene is located on chromosome 16 and encodes a 78 kDa protein with multiple functional domains including an ubiquitin-binding domain and a catalytic domain. As a deubiquitinase, USP10 plays a critical role in regulating protein stability, localization, and function by catalyzing the removal of polyubiquitin chains from substrate proteins. This enzymatic activity makes USP10 a key regulator of cellular proteostasis—the maintenance of proper protein balance within cells—a process fundamentally disrupted in neurodegenerative diseases.
Function/Biology
USP10 functions as a hydrolase that cleaves isopeptide bonds between ubiquitin molecules and target proteins, primarily removing lysine-63 (K63) linked polyubiquitin chains, though it can also process K48-linked chains and monoubiquitinated substrates depending on cellular context. The protein localizes to both the cytoplasm and nucleus, with subcellular distribution regulated by post-translational modifications and protein-protein interactions.
...USP10 Protein
Overview
USP10 (ubiquitin-specific protease 10) is a deubiquitinating enzyme belonging to the ubiquitin-specific protease (USP) family, a large class of cysteine proteases that remove ubiquitin modifications from target proteins. The USP10 gene is located on chromosome 16 and encodes a 78 kDa protein with multiple functional domains including an ubiquitin-binding domain and a catalytic domain. As a deubiquitinase, USP10 plays a critical role in regulating protein stability, localization, and function by catalyzing the removal of polyubiquitin chains from substrate proteins. This enzymatic activity makes USP10 a key regulator of cellular proteostasis—the maintenance of proper protein balance within cells—a process fundamentally disrupted in neurodegenerative diseases.
Function/Biology
USP10 functions as a hydrolase that cleaves isopeptide bonds between ubiquitin molecules and target proteins, primarily removing lysine-63 (K63) linked polyubiquitin chains, though it can also process K48-linked chains and monoubiquitinated substrates depending on cellular context. The protein localizes to both the cytoplasm and nucleus, with subcellular distribution regulated by post-translational modifications and protein-protein interactions.
The catalytic activity of USP10 requires a conserved catalytic triad consisting of cysteine, histidine, and aspartic acid residues. Upon ubiquitin substrate binding, these residues facilitate nucleophilic attack on the ubiquitin-substrate isopeptide bond, releasing free ubiquitin and regenerating the deubiquitinated protein substrate. This deubiquitination activity is reversible by E3 ligases, allowing cells to dynamically regulate protein ubiquitination status in response to cellular conditions.
USP10 regulates multiple cellular processes including protein trafficking, transcriptional regulation, signal transduction, and stress responses. The protein interacts with various cellular proteins and can be itself modified by ubiquitination, phosphorylation, and other post-translational modifications that modulate its activity and localization.
Role in Neurodegeneration
USP10 has emerged as an important regulator in multiple neurodegenerative pathways. Research has identified USP10 as a critical modulator of p53 stability and function. The tumor suppressor protein p53 accumulates under cellular stress and triggers protective mechanisms; however, excessive p53 activation can promote neuronal apoptosis. USP10-mediated deubiquitination of p53 regulates its stability, and dysregulation of this pathway contributes to neuronal death observed in Parkinson's disease and other conditions.
USP10 also plays a role in regulating tau protein metabolism. Tau hyperphosphorylation and aggregation characterize Alzheimer's disease pathology, and USP10-mediated deubiquitination influences tau protein stability and clearance mechanisms. Additionally, USP10 regulates autophagy through modulation of autophagy-related proteins, affecting the clearance of misfolded protein aggregates that accumulate in Alzheimer's disease, Parkinson's disease, and other proteinopathies.
In ALS (amyotrophic lateral sclerosis), USP10 regulates TDP-43 protein processing and turnover. TDP-43 mislocalization and aggregation characterize most ALS cases, and USP10 activity influences TDP-43 ubiquitination status and consequent protein degradation through the proteasome and autophagy pathways.
Molecular Mechanisms
USP10 exerts neuroprotective effects through several interconnected mechanisms. The protein suppresses p53-mediated apoptosis by removing ubiquitin modifications that target p53 for degradation, thereby modulating p53 protein levels to maintain a balance between protective and pro-apoptotic functions. Under genotoxic or proteotoxic stress, USP10 activity can be dynamically altered to allow appropriate p53 responses.
USP10 also regulates cellular stress responses through modulation of heat shock factor 1 (HSF1) and heat shock proteins, which are critical for protein folding and disaggregation. By controlling the ubiquitination status of these proteins, USP10 influences the cellular heat shock response capacity, affecting neuronal resilience to proteotoxic insults.
The protein functions within broader ubiquitin signaling networks, competing with ubiquitinating enzymes and interacting with ubiquitin-binding proteins to determine the ultimate fate of substrates—including proteasomal degradation, autophagy-mediated clearance, or functional modification.
Clinical/Research Significance
USP10 represents a therapeutic target for neurodegenerative diseases. Modulating USP10 activity could enhance cellular protein quality control, reduce accumulation of pathogenic protein aggregates, and limit neuronal apoptosis. Pharmacological USP10 inhibitors or activators are under investigation as potential disease-modifying treatments.
Genetic studies have explored USP10 polymorphisms and expression levels in neurodegenerative disease cohorts, seeking associations with disease risk and progression. Understanding how USP10 dysfunction contributes to neurodegen