Deubiquitinating enzyme (DUB) that controls levels of cellular ubiquitin through processing of ubiquitin precursors and ubiquitinated proteins. Thiol protease that recognizes and hydrolyzes a peptide bond at the C-terminal glycine of either ubiquitin or NEDD8. Has a 10-fold preference for Arg and Lys at position P3", and exhibits a preference towards 'Lys-48'-linked Ubiquitin chains. Deubiquitinates ENAC in apical compartments, thereby regulating apical membrane recycling. Indirectly increases the phosphorylation of IGFIR, AKT and FOXO1 and promotes insulin-signaling and insulin-induced adipogenesis. Required for stress-response retinal, skeletal muscle and germ cell maintenance. May be involved in working memory. Can hydrolyze UBB(+1), a mutated form of ubiquitin which is not effectively degraded by the proteasome and is associated with neurogenerative disorders.
Mutant ubiquitin (UBB(+1)) accumulates in the hallmarks of tauopathies and polyglutamine diseases. We show that the deubiquitinating enzyme YUH1 of Saccharomyces cerevisiae and its mouse and human ortholog UCH-L3 are able to hydrolyze the C-terminal extension of UBB(+1). This yields another dysfunctional ubiquitin molecule (UB(G76Y)) with biochemical properties similar to full length UBB(+1). UBB(+1) may be detected in post-mortem tissue due to impaired C-terminal truncation of UBB(+1). Although the level of UCH-L3 protein in several neurodegenerative diseases is unchanged, we show that in vitro oxidation of recombinant UCH-L3 impairs its deubiquitinating activity. We postulate that impaired UCH-L3 function may contribute to the accumulation of full length UBB(+1) in various pathologies.
NEDD8 is a novel ubiquitin-like protein that has been shown to conjugate to nuclear proteins in a manner analogous to ubiquitination and sentrinization. To identify proteins that are involved in the NEDD8-conjugation and de-conjugation pathway, the yeast two-hybrid system was used to screen a human heart cDNA library using NEDD8 as a bait. Seven strongly positive clones were found to contain a cDNA insert encoding the ubiquitin C-terminal hydrolase, UCH-L3. In vitro GST pull-down assay demonstrated that UCH-L3 bound to both NEDD8 and ubiquitin. In contrast, UCH-L3 did not bind to sentrin-1, sentrin-2, or sentrin-3. Recombinant UCH-L3, but not UCH-L1, was able to cleave the C-terminus of NEDD8. Thus, UCH-L3 can function as a C-terminal hydrolase for both NEDD8 and ubiquitin. UCH-L3 may play a physiologically significant role in the cleavage of the C-terminus of NEDD8, which is required for NEDD8 to conjugate to target proteins.
A complementary DNA (cDNA) for ubiquitin carboxyl-terminal hydrolase isozyme L3 was cloned from human B cells. The cDNA encodes a protein of 230 amino acids with a molecular mass of 26.182 daltons. The human protein is very similar to the bovine homolog, with only three amino acids differing in over 100 residues compared. The amino acid sequence deduced from the cDNA was 54% identical to that of the neuron-specific protein PGP 9.5. Purification of bovine PGP 9.5 confirmed that it is also a ubiquitin carboxyl-terminal hydrolase. These results suggest that a family of such related proteins exists and that their expression is tissue-specific.
Ubiquitin (Ub) carboxy terminal hydrolase (UCH)-L1 and UCH-L3 are two of the deubiquitinating enzymes expressed in the brain. Both gad mice, which lack UCH-L1 expression and Uchl3 knockout mice exhibit neurodegeneration, although at distinct areas. These phenotypes indicate the importance of UCH-L1 and UCH-L3 in the regulation of the central nervous system. However, molecular substrates and the molecular regulators of UCH-L1 and UCH-L3 remain poorly identified. Here we show that Ub dimers interact non-covalently with UCH-L3 in vitro and in cells. These interactions were not observed with UCH-L1 in cells. In vitro, K48-linked Ub dimers pronouncedly inhibited the hydrolase activity of UCH-L3, while mono-Ub, a previously identified interacting protein, inhibited the hydrolase activity of UCH-L1. These results indicate that mono-Ub and Ub dimers may regulate the enzymatic functions of UCH-L1 and UCH-L3, respectively, in vivo.
Catalysis of the hydrolysis of peptide bonds in a polypeptide chain by a mechanism in which the sulfhydryl group of a cysteine residue at the active center acts as a nucleophile.
Catalysis of the hydrolysis of a peptide bond. A peptide bond is a covalent bond formed when the carbon atom from the carboxyl group of one amino acid shares electrons with the nitrogen atom from the amino group of a second amino acid.
Mutant ubiquitin (UBB(+1)) accumulates in the hallmarks of tauopathies and polyglutamine diseases. We show that the deubiquitinating enzyme YUH1 of Saccharomyces cerevisiae and its mouse and human ortholog UCH-L3 are able to hydrolyze the C-terminal extension of UBB(+1). This yields another dysfunctional ubiquitin molecule (UB(G76Y)) with biochemical properties similar to full length UBB(+1). UBB(+1) may be detected in post-mortem tissue due to impaired C-terminal truncation of UBB(+1). Although the level of UCH-L3 protein in several neurodegenerative diseases is unchanged, we show that in vitro oxidation of recombinant UCH-L3 impairs its deubiquitinating activity. We postulate that impaired UCH-L3 function may contribute to the accumulation of full length UBB(+1) in various pathologies.
Interacting selectively and non-covalently with ubiquitin, a protein that when covalently bound to other cellular proteins marks them for proteolytic degradation.
Ubiquitin (Ub) carboxy terminal hydrolase (UCH)-L1 and UCH-L3 are two of the deubiquitinating enzymes expressed in the brain. Both gad mice, which lack UCH-L1 expression and Uchl3 knockout mice exhibit neurodegeneration, although at distinct areas. These phenotypes indicate the importance of UCH-L1 and UCH-L3 in the regulation of the central nervous system. However, molecular substrates and the molecular regulators of UCH-L1 and UCH-L3 remain poorly identified. Here we show that Ub dimers interact non-covalently with UCH-L3 in vitro and in cells. These interactions were not observed with UCH-L1 in cells. In vitro, K48-linked Ub dimers pronouncedly inhibited the hydrolase activity of UCH-L3, while mono-Ub, a previously identified interacting protein, inhibited the hydrolase activity of UCH-L1. These results indicate that mono-Ub and Ub dimers may regulate the enzymatic functions of UCH-L1 and UCH-L3, respectively, in vivo.
Catalysis of the reaction: ubiquitin C-terminal thiolester + H2O = ubiquitin + a thiol. Hydrolysis of esters, including those formed between thiols such as dithiothreitol or glutathione and the C-terminal glycine residue of the polypeptide ubiquitin, and AMP-ubiquitin.
A complementary DNA (cDNA) for ubiquitin carboxyl-terminal hydrolase isozyme L3 was cloned from human B cells. The cDNA encodes a protein of 230 amino acids with a molecular mass of 26.182 daltons. The human protein is very similar to the bovine homolog, with only three amino acids differing in over 100 residues compared. The amino acid sequence deduced from the cDNA was 54% identical to that of the neuron-specific protein PGP 9.5. Purification of bovine PGP 9.5 confirmed that it is also a ubiquitin carboxyl-terminal hydrolase. These results suggest that a family of such related proteins exists and that their expression is tissue-specific.
The chemical reactions and pathways resulting in the breakdown of a protein by the destruction of the native, active configuration, with or without the hydrolysis of peptide bonds.
Mutant ubiquitin (UBB(+1)) accumulates in the hallmarks of tauopathies and polyglutamine diseases. We show that the deubiquitinating enzyme YUH1 of Saccharomyces cerevisiae and its mouse and human ortholog UCH-L3 are able to hydrolyze the C-terminal extension of UBB(+1). This yields another dysfunctional ubiquitin molecule (UB(G76Y)) with biochemical properties similar to full length UBB(+1). UBB(+1) may be detected in post-mortem tissue due to impaired C-terminal truncation of UBB(+1). Although the level of UCH-L3 protein in several neurodegenerative diseases is unchanged, we show that in vitro oxidation of recombinant UCH-L3 impairs its deubiquitinating activity. We postulate that impaired UCH-L3 function may contribute to the accumulation of full length UBB(+1) in various pathologies.
The chemical reactions and pathways resulting in the breakdown of a protein or peptide by hydrolysis of its peptide bonds, initiated by the covalent attachment of a ubiquitin group, or multiple ubiquitin groups, to the protein.
NASUniProtKB Annot
Enzymatic activity
This protein acts as an enzyme. It is known to catalyze the following reaction
EC 3.4.19.12: Thiol-dependent hydrolysis of ester, thioester, amide, peptide and isopeptide bonds formed by the C-terminal Gly of ubiquitin (a 76-residue protein attached to proteins as an intracellular targeting signal).
NEDD8 is a novel ubiquitin-like protein that has been shown to conjugate to nuclear proteins in a manner analogous to ubiquitination and sentrinization. To identify proteins that are involved in the NEDD8-conjugation and de-conjugation pathway, the yeast two-hybrid system was used to screen a human heart cDNA library using NEDD8 as a bait. Seven strongly positive clones were found to contain a cDNA insert encoding the ubiquitin C-terminal hydrolase, UCH-L3. In vitro GST pull-down assay demonstrated that UCH-L3 bound to both NEDD8 and ubiquitin. In contrast, UCH-L3 did not bind to sentrin-1, sentrin-2, or sentrin-3. Recombinant UCH-L3, but not UCH-L1, was able to cleave the C-terminus of NEDD8. Thus, UCH-L3 can function as a C-terminal hydrolase for both NEDD8 and ubiquitin. UCH-L3 may play a physiologically significant role in the cleavage of the C-terminus of NEDD8, which is required for NEDD8 to conjugate to target proteins.
Ubiquitin C-terminal hydrolase (UCH)-L3 is an enzyme with a strongly suggested de-ubiquitinating function by in vitro studies, but has poorly been investigated in vivo. In this study, we show that skeletal muscles of Uchl3(-/-) mice exhibit the up-regulation of cleaved ATF6, Grp78, and PDI as well as HSP27, HSP70, HSP90 and HSP110, which indicate the induction of stress responses. The prominent accumulation of polyubiquitinated proteins, one of the factors reported to induce stress responses, was observed in the skeletal muscle of Uchl3(-/-) mice. Mouse embryonic fibroblasts (MEFs) from Uchl3(-/-) mice also showed an accumulation of polyubiquitinated proteins. Moreover, the polyubiquitinated protein accumulation in Uchl3(-/-) MEFs was attenuated by the exogenous expression of wild-type, but not hydrolase activity deficient, UCH-L3. In addition, wild-type, but not its hydrolase activity or ubiquitin binding activity deficient UCH-L3 showed the ability to cleave ubiquitin from polyubiquitinated lysozyme in vitro. These results suggest that UCH-L3 functions as a de-ubiquitinating enzyme in vivo where lack of its hydrolase activity may result in the prominent accumulation of ubiquitinated proteins and subsequent induction of stress responses in skeletal muscle.
Ubiquitin C-terminal hydrolases (UCHs) comprise a family of small ubiquitin-specific proteases of uncertain function. Although no cellular substrates have been identified for UCHs, their highly tissue-specific expression patterns and the association of UCH-L1 mutations with human disease strongly suggest a critical role. The structure of the yeast UCH Yuh1-ubiquitin aldehyde complex identified an active site crossover loop predicted to limit the size of suitable substrates. We report the 1.45 A resolution crystal structure of human UCH-L3 in complex with the inhibitor ubiquitin vinylmethylester, an inhibitor that forms a covalent adduct with the active site cysteine of ubiquitin-specific proteases. This structure confirms the predicted mechanism of the inhibitor and allows the direct comparison of a UCH family enzyme in the free and ligand-bound state. We also show the efficient hydrolysis by human UCH-L3 of a 13-residue peptide in isopeptide linkage with ubiquitin, consistent with considerable flexibility in UCH substrate size. We propose a model for the catalytic cycle of UCH family members which accounts for the hydrolysis of larger ubiquitin conjugates.
Ubiquitin (Ub) carboxy terminal hydrolase (UCH)-L1 and UCH-L3 are two of the deubiquitinating enzymes expressed in the brain. Both gad mice, which lack UCH-L1 expression and Uchl3 knockout mice exhibit neurodegeneration, although at distinct areas. These phenotypes indicate the importance of UCH-L1 and UCH-L3 in the regulation of the central nervous system. However, molecular substrates and the molecular regulators of UCH-L1 and UCH-L3 remain poorly identified. Here we show that Ub dimers interact non-covalently with UCH-L3 in vitro and in cells. These interactions were not observed with UCH-L1 in cells. In vitro, K48-linked Ub dimers pronouncedly inhibited the hydrolase activity of UCH-L3, while mono-Ub, a previously identified interacting protein, inhibited the hydrolase activity of UCH-L1. These results indicate that mono-Ub and Ub dimers may regulate the enzymatic functions of UCH-L1 and UCH-L3, respectively, in vivo.
Protein involved in ubiquitin-like modifier processing, activation, conjugation or deconjugation such as Ubl-activating enzymes (E1s), Ubl-conjugating enzymes (E2s), Ubl-protein ligases (E3s), some thiol proteases (Ubiquitin carboxyl-terminal hydrolases (UCH), Ubiquitin- specific processing proteases (UBP) and ubiquitin-like proteases) and the ubiquitin-like modifier proteins. Besides signaling proteolysis, ubiquitination for example can be a signal for trafficking, kinase activation and other nonproteolytic fates.
Enzyme which catalyzes hydrolysis reaction, i.e. the addition of the hydrogen and hydroxyl ions of water to a molecule with its consequent splitting into two or more simpler molecules.
Proteolytic enzyme with a cysteine residue (Cys) in its active site. There are many families of thiol proteases. The most well known one is the papain family (C1 in MEROPS classification) which is known to exist in most eukaryotes.
A reference proteome is a set of protein sequences derived from a complete proteome which constitutes a defined standard for a particular user community. Reference proteomes are manually defined according to a number of criteria. They cover the proteomes of well- studied model organisms and other proteomes of interest for biomedical and biotechnological research. Reference proteomes have been selected to provide broad coverage of the tree of life, and constitute a representative cross-section of the taxonomic diversity to be found within UniProtKB.