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1
de Palma, Luigi, Mario Marinelli, Matteo Pavan, and Alessandro Orazi. "Rôle des ubiquitine ligases MuRF1 et MAFbx dans l’atrophie musculaire chez l’homme." Revue du Rhumatisme 75, no. 1 (January 2008): 56–60. http://dx.doi.org/10.1016/j.rhum.2007.04.021.
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Reboud-Ravaux, Michèle. "Dégradation induite des protéines par des molécules PROTAC et stratégies apparentées : développements à visée thérapeutique." Biologie Aujourd’hui 215, no. 1-2 (2021): 25–43. http://dx.doi.org/10.1051/jbio/2021007.
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Alors que, pour la plupart, les médicaments actuels sont de petites molécules inhibant l’action d’une protéine en bloquant un site d’interaction, la dégradation ciblée des protéines, découverte il y a une vingtaine d’années via les petites molécules PROTAC, connaît aujourd’hui un très grand développement, aussi bien au niveau universitaire qu’industriel. Cette dégradation ciblée permet de contrôler la concentration intracellulaire d’une protéine spécifique comme peuvent le faire les techniques basées sur les acides nucléiques (oligonucléotides antisens, ARNsi, CRISPR-Cas9). Les molécules PROTAC sont des chimères hétéro-bifonctionnelles capables de lier simultanément une protéine spécifique devant être dégradée et une E3 ubiquitine ligase. Les PROTAC sont donc capables de provoquer l’ubiquitinylation de la protéine ciblée et sa dégradation par le protéasome 26S. De nature peptidique, puis non peptidique, les PROTAC sont maintenant administrables par voie orale. Ce détournement du système ubiquitine protéasome permet aux molécules PROTAC d’élargir considérablement le champ des applications thérapeutiques puisque l’élimination de protéines dépourvues de poches ou de crevasses bien définies, dites difficiles à cibler, devient possible. Cette technologie versatile a conduit à la dégradation d’une grande variété de protéines comme des facteurs de transcription, des sérine/thréonine/tyrosine kinases, des protéines de structure, des protéines cytosoliques, des lecteurs épigénétiques. Certaines ligases telles que VHL, MDM2, cereblon et IAP sont couramment utilisées pour être recrutées par les PROTAC. Actuellement, le nombre de ligases pouvant être utilisées ainsi que la nature des protéines dégradées sont en constante augmentation. Deux PROTAC sont en étude clinique pour les cancers du sein (ARV471) et de la prostate (ARV110). La dégradation spécifique d’une protéine par le protéasome peut aussi être induite par d’autres types de molécules synthétiques : colles moléculaires, marqueurs hydrophobes, HaloPROTAC, homo-PROTAC. D’autres constituants cellulaires sont aussi éligibles à une dégradation induite : ARN-PROTAC pour les protéines se liant à l’ARN et RIBOTAC pour la dégradation de l’ARN lui-même comme celui du SARS-CoV-2. Des dégradations induites en dehors du protéasome sont aussi connues : LYTAC, pour des chimères détournant la dégradation de protéines extracellulaires vers les lysosomes, et MADTAC, pour des chimères détournant la dégradation par macroautophagie. Plusieurs techniques, en particulier des plates-formes de criblage, la modélisation mathématique et la conception computationnelle sont utilisées pour le développement de nouveaux PROTAC efficaces.
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Dumétier, Baptiste, Aymeric Zadoroznyj, and Laurence Dubrez. "IAP-Mediated Protein Ubiquitination in Regulating Cell Signaling." Cells 9, no. 5 (April 30, 2020): 1118. http://dx.doi.org/10.3390/cells9051118.
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Over the last decade, the E3-ubiquitine ligases from IAP (Inhibitor of Apoptosis) family have emerged as potent regulators of immune response. In immune cells, they control signaling pathways driving differentiation and inflammation in response to stimulation of tumor necrosis factor receptor (TNFR) family, pattern-recognition receptors (PRRs), and some cytokine receptors. They are able to control the activity, the cellular fate, or the stability of actors of signaling pathways, acting at different levels from components of receptor-associated multiprotein complexes to signaling effectors and transcription factors, as well as cytoskeleton regulators. Much less is known about ubiquitination substrates involved in non-immune signaling pathways. This review aimed to present IAP ubiquitination substrates and the role of IAP-mediated ubiquitination in regulating signaling pathways.
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Taillandier, Daniel. "Contrôle des voies métaboliques par les enzymes E3 ligases : une opportunité de ciblage thérapeutique." Biologie Aujourd’hui 215, no. 1-2 (2021): 45–57. http://dx.doi.org/10.1051/jbio/2021006.
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Depuis sa découverte, le Système Ubiquitine Protéasome (UPS) est reconnu pour son rôle majeur dans le contrôle de la plupart des voies métaboliques de la cellule. Outre son rôle primordial dans la dégradation des protéines, il intervient aussi dans l’adressage, la signalisation ou la réparation de l’ADN, ce qui en fait un acteur incontournable de l’homéostasie cellulaire. Bien que d’autres systèmes de contrôles existent dans la cellule, l’UPS est souvent considéré comme le chef d’orchestre. Au vu de son importance, toute dérégulation de l’UPS entraîne des désordres plus ou moins sévères pour la cellule et donc l’organisme. De fait, l’UPS est impliqué dans de nombreuses pathologies (cancer, maladie d’Alzheimer, de Huntington, etc.). L’UPS est composé de plus de 1000 protéines différentes dont les combinaisons permettent le ciblage fin de virtuellement toutes les protéines de l’organisme. L’UPS fait appel à une cascade enzymatique (E1, 2 isoformes ; E2 > 35 isoformes ; E3 > 800 isoformes) qui permet le transfert de l’ubiquitine, une petite protéine de 8,5 kDa, sur la protéine à cibler soit pour sa dégradation, soit pour modifier son activité. Ce signal d’ubiquitinylation est réversible et de nombreuses déubiquitinylases (DUB, ∼ 80 isoformes) jouent aussi un rôle important. Les enzymes E3 sont les plus nombreuses et leur fonction est de reconnaître la protéine cible, ce qui en fait des acteurs importants dans la spécificité d’action de l’UPS. La nature même des E3 et la complexité de leurs interactions avec différents partenaires offrent un champ d’investigation très large et donc des potentialités importantes pour le développement d’approches thérapeutiques. Sans être exhaustive, cette revue illustre les différentes stratégies ayant déjà été mises en œuvre pour lutter contre différentes pathologies (à l’exclusion des infections bactériennes ou virales).
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Lee, Jaeseok, Youngjun Lee, Young Mee Jung, Ju Hyun Park, Hyuk Sang Yoo, and Jongmin Park. "Discovery of E3 Ligase Ligands for Target Protein Degradation." Molecules 27, no. 19 (October 2, 2022): 6515. http://dx.doi.org/10.3390/molecules27196515.
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Target protein degradation has emerged as a promising strategy for the discovery of novel therapeutics during the last decade. Proteolysis-targeting chimera (PROTAC) harnesses a cellular ubiquitin-dependent proteolysis system for the efficient degradation of a protein of interest. PROTAC consists of a target protein ligand and an E3 ligase ligand so that it enables the target protein degradation owing to the induced proximity with ubiquitin ligases. Although a great number of PROTACs has been developed so far using previously reported ligands of proteins for their degradation, E3 ligase ligands have been mostly limited to either CRBN or VHL ligands. Those PROTACs showed their limitation due to the cell type specific expression of E3 ligases and recently reported resistance toward PROTACs with CRBN ligands or VHL ligands. To overcome these hurdles, the discovery of various E3 ligase ligands has been spotlighted to improve the current PROTAC technology. This review focuses on currently reported E3 ligase ligands and their application in the development of PROTACs.
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Del Prete, Dolores, Richard C. Rice, Anjali M. Rajadhyaksha, and Luciano D'Adamio. "Amyloid Precursor Protein (APP) May Act as a Substrate and a Recognition Unit for CRL4CRBN and Stub1 E3 Ligases Facilitating Ubiquitination of Proteins Involved in Presynaptic Functions and Neurodegeneration." Journal of Biological Chemistry 291, no. 33 (June 20, 2016): 17209–27. http://dx.doi.org/10.1074/jbc.m116.733626.
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The amyloid precursor protein (APP), whose mutations cause Alzheimer disease, plays an important in vivo role and facilitates transmitter release. Because the APP cytosolic region (ACR) is essential for these functions, we have characterized its brain interactome. We found that the ACR interacts with proteins that regulate the ubiquitin-proteasome system, predominantly with the E3 ubiquitin-protein ligases Stub1, which binds the NH2 terminus of the ACR, and CRL4CRBN, which is formed by Cul4a/b, Ddb1, and Crbn, and interacts with the COOH terminus of the ACR via Crbn. APP shares essential functions with APP-like protein-2 (APLP2) but not APP-like protein-1 (APLP1). Noteworthy, APLP2, but not APLP1, interacts with Stub1 and CRL4CRBN, pointing to a functional pathway shared only by APP and APLP2. In vitro ubiquitination/ubiquitome analysis indicates that these E3 ligases are enzymatically active and ubiquitinate the ACR residues Lys649/650/651/676/688. Deletion of Crbn reduces ubiquitination of Lys676 suggesting that Lys676 is physiologically ubiquitinated by CRL4CRBN. The ACR facilitated in vitro ubiquitination of presynaptic proteins that regulate exocytosis, suggesting a mechanism by which APP tunes transmitter release. Other dementia-related proteins, namely Tau and apoE, interact with and are ubiquitinated via the ACR in vitro. This, and the evidence that CRBN and CUL4B are linked to intellectual disability, prompts us to hypothesize a pathogenic mechanism, in which APP acts as a modulator of E3 ubiquitin-protein ligase(s), shared by distinct neuronal disorders. The well described accumulation of ubiquitinated protein inclusions in neurodegenerative diseases and the link between the ubiquitin-proteasome system and neurodegeneration make this concept plausible.
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Kim, Jong Hum, Seok Keun Cho, Tae Rin Oh, Moon Young Ryu, Seong Wook Yang, and Woo Taek Kim. "MPSR1 is a cytoplasmic PQC E3 ligase for eliminating emergent misfolded proteins in Arabidopsis thaliana." Proceedings of the National Academy of Sciences 114, no. 46 (October 30, 2017): E10009—E10017. http://dx.doi.org/10.1073/pnas.1713574114.
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Ubiquitin E3 ligases are crucial for eliminating misfolded proteins before they form cytotoxic aggregates that threaten cell fitness and survival. However, it remains unclear how emerging misfolded proteins in the cytoplasm can be selectively recognized and eliminated by E3 ligases in plants. We found that Misfolded Protein Sensing RING E3 ligase 1 (MPSR1) is an indispensable E3 ligase required for plant survival after protein-damaging stress. Under no stress, MPSR1 is prone to rapid degradation by the 26S proteasome, concealing its protein quality control (PQC) E3 ligase activity. Upon proteotoxic stress, MPSR1 directly senses incipient misfolded proteins and tethers ubiquitins for subsequent degradation. Furthermore, MPSR1 sustains the structural integrity of the proteasome complex at the initial stage of proteotoxic stress. Here, we suggest that the MPSR1 pathway is a constitutive mechanism for proteostasis under protein-damaging stress, as a front-line surveillance system in the cytoplasm.
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Windheim, Mark, Mark Peggie, and Philip Cohen. "Two different classes of E2 ubiquitin-conjugating enzymes are required for the mono-ubiquitination of proteins and elongation by polyubiquitin chains with a specific topology." Biochemical Journal 409, no. 3 (January 15, 2008): 723–29. http://dx.doi.org/10.1042/bj20071338.
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RING (really interesting new gene) and U-box E3 ligases bridge E2 ubiquitin-conjugating enzymes and substrates to enable the transfer of ubiquitin to a lysine residue on the substrate or to one of the seven lysine residues of ubiquitin for polyubiquitin chain elongation. Different polyubiquitin chains have different functions. Lys48-linked chains target proteins for proteasomal degradation, and Lys63-linked chains function in signal transduction, endocytosis and DNA repair. For this reason, chain topology must be tightly controlled. Using the U-box E3 ligase CHIP [C-terminus of the Hsc (heat-shock cognate) 70-interacting protein] and the RING E3 ligase TRAF6 (tumour-necrosis-factor-receptor-associated factor 6) with the E2s Ubc13 (ubiquitin-conjugating enzyme 13)–Uev1a (ubiquitin E2 variant 1a) and UbcH5a, in the present study we demonstrate that Ubc13–Uev1a supports the formation of free Lys63-linked polyubiquitin chains not attached to CHIP or TRAF6, whereas UbcH5a catalyses the formation of polyubiquitin chains linked to CHIP and TRAF6 that lack specificity for any lysine residue of ubiquitin. Therefore the abilities of these E2s to ubiquitinate a substrate and to elongate polyubiquitin chains of a specific topology appear to be mutually exclusive. Thus two different classes of E2 may be required to attach a polyubiquitin chain of a particular topology to a substrate: the properties of one E2 are designed to mono-ubiquitinate a substrate with no or little inherent specificity for an acceptor lysine residue, whereas the properties of the second E2 are tailored to the elongation of a polyubiquitin chain using a defined lysine residue of ubiquitin.
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Tracz, Michał, Ireneusz Górniak, Andrzej Szczepaniak, and Wojciech Białek. "E3 Ubiquitin Ligase SPL2 Is a Lanthanide-Binding Protein." International Journal of Molecular Sciences 22, no. 11 (May 27, 2021): 5712. http://dx.doi.org/10.3390/ijms22115712.
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The SPL2 protein is an E3 ubiquitin ligase of unknown function. It is one of only three types of E3 ligases found in the outer membrane of plant chloroplasts. In this study, we show that the cytosolic fragment of SPL2 binds lanthanide ions, as evidenced by fluorescence measurements and circular dichroism spectroscopy. We also report that SPL2 undergoes conformational changes upon binding of both Ca2+ and La3+, as evidenced by its partial unfolding. However, these structural rearrangements do not interfere with SPL2 enzymatic activity, as the protein retains its ability to auto-ubiquitinate in vitro. The possible applications of lanthanide-based probes to identify protein interactions in vivo are also discussed. Taken together, the results of this study reveal that the SPL2 protein contains a lanthanide-binding site, showing for the first time that at least some E3 ubiquitin ligases are also capable of binding lanthanide ions.
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Qian, Hao, Ying Zhang, Boquan Wu, Shaojun Wu, Shilong You, Naijin Zhang, and Yingxian Sun. "Structure and function of HECT E3 ubiquitin ligases and their role in oxidative stress." Journal of Translational Internal Medicine 8, no. 2 (June 30, 2020): 71–79. http://dx.doi.org/10.2478/jtim-2020-0012.
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AbstractUbiquitination is a modification after protein transcription that plays a vital role in maintaining the homeostasis of the cellular environment. The Homologous to E6AP C-terminus (HECT) family E3 ubiquitin ligases are a kind of E3 ubiquitin ligases with a C-terminal HECT domain that mediates the binding of ubiquitin to substrate proteins and a variable-length N-terminal extension. HECT-ubiquitinated ligases can be divided into three categories: NEDD4 superfamily, HERC superfamily, and other HECT superfamilies. HECT ubiquitin ligase plays an essential role in the development of many human diseases. In this review, we focus on the physiological and pathological processes involved in oxidative stress and the role of E3 ubiquitin ligase of the HECT family.
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Kelley, Dior R. "E3 Ubiquitin Ligases: Key Regulators of Hormone Signaling in Plants." Molecular & Cellular Proteomics 17, no. 6 (March 7, 2018): 1047–54. http://dx.doi.org/10.1074/mcp.mr117.000476.
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Ubiquitin-mediated control of protein stability is central to most aspects of plant hormone signaling. Attachment of ubiquitin to target proteins occurs via an enzymatic cascade with the final step being catalyzed by a family of enzymes known as E3 ubiquitin ligases, which have been classified based on their protein domains and structures. Although E3 ubiquitin ligases are conserved among eukaryotes, in plants they are well-known to fulfill unique roles as central regulators of phytohormone signaling, including hormone perception and regulation of hormone biosynthesis. This review will highlight up-to-date findings that have refined well-known E3 ligase-substrate interactions and defined novel E3 ligase substrates that mediate numerous hormone signaling pathways. Additionally, examples of how particular E3 ligases may mediate hormone crosstalk will be discussed as an emerging theme. Looking forward, promising experimental approaches and methods that will provide deeper mechanistic insight into the roles of E3 ubiquitin ligases in plants will be considered.
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Martin-Serrano, Juan, Scott W. Eastman, Wayne Chung, and Paul D. Bieniasz. "HECT ubiquitin ligases link viral and cellular PPXY motifs to the vacuolar protein-sorting pathway." Journal of Cell Biology 168, no. 1 (December 28, 2004): 89–101. http://dx.doi.org/10.1083/jcb.200408155.
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Many enveloped viruses exploit the class E vacuolar protein-sorting (VPS) pathway to bud from cells, and use peptide motifs to recruit specific class E VPS factors. Homologous to E6AP COOH terminus (HECT) ubiquitin ligases have been implicated as cofactors for PPXY motif–dependent budding, but precisely which members of this family are responsible, and how they access the VPS pathway is unclear. Here, we show that PPXY-dependent viral budding is unusually sensitive to inhibitory fragments derived from specific HECT ubiquitin ligases, namely WWP1 and WWP2. We also show that WWP1, WWP2, or Itch ubiquitin ligase recruitment promotes PPXY-dependent virion release, and that this function requires that the HECT ubiquitin ligase domain be catalytically active. Finally, we show that several mammalian HECT ubiquitin ligases, including WWP1, WWP2, and Itch are recruited to class E compartments induced by dominant negative forms of the class E VPS ATPase, VPS4. These data indicate that specific HECT ubiquitin ligases can link PPXY motifs to the VPS pathway to induce viral budding.
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Marblestone, Jeffrey G., K. G. Suresh Kumar, Michael J. Eddins, Craig A. Leach, David E. Sterner, Michael R. Mattern, and Benjamin Nicholson. "Novel Approach for Characterizing Ubiquitin E3 Ligase Function." Journal of Biomolecular Screening 15, no. 10 (September 23, 2010): 1220–28. http://dx.doi.org/10.1177/1087057110380456.
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The ubiquitin-proteasome system is central to the regulation of numerous cellular events, and dysregulation may lead to disease pathogenesis. E3 ubiquitin ligases typically function in concert with E1 and E2 enzymes to recruit specific substrates, thereby coordinating their ubiquitylation and subsequent proteasomal degradation or cellular activity. E3 ligases have been implicated in a wide range of pathologies, and monitoring their activity in a rapid and cost-effective manner would be advantageous in drug discovery. The relative lack of high-throughput screening (HTS)–compliant E3 ligase assays has significantly hindered the discovery of E3 inhibitors. Herein, the authors describe a novel HTS-compliant E3 ligase assay platform that takes advantage of a ubiquitin binding domain’s inherent affinity for polyubiquitin chains, permitting the analysis of ubiquitin chain formation in an E3 ligase-dependent manner. This assay has been used successfully with members of both the RING and HECT families, demonstrating the platform’s broad utility for analyzing a wide range of E3 ligases. The utility of the assay platform is demonstrated by the identification of inhibitors of the E3 ligase CARP2. As the number of E3 ligases associated with various disease states increases, the ability to quantitate the activity of these enzymes in an expeditious manner becomes imperative in drug discovery.
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Yoshida, Yukiko, Yasushi Saeki, Arisa Murakami, Junko Kawawaki, Hikaru Tsuchiya, Hidehito Yoshihara, Mayumi Shindo, and Keiji Tanaka. "A comprehensive method for detecting ubiquitinated substrates using TR-TUBE." Proceedings of the National Academy of Sciences 112, no. 15 (March 31, 2015): 4630–35. http://dx.doi.org/10.1073/pnas.1422313112.
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The identification of substrates for ubiquitin ligases has remained challenging, because most substrates are either immediately degraded by the proteasome or processed by deubiquitinating enzymes (DUBs) to remove polyubiquitin. Although a methodology that enables detection of ubiquitinated proteins using ubiquitin Lys-ε-Gly-Gly (diGly) remnant antibodies and MS has been developed, it is still insufficient for identification and characterization of the ubiquitin-modified proteome in cells overexpressing a particular ubiquitin ligase. Here, we show that exogenously expressed trypsin-resistant tandem ubiquitin-binding entity(ies) (TR-TUBE) protect polyubiquitin chains on substrates from DUBs and circumvent proteasome-mediated degradation in cells. TR-TUBE effectively associated with substrates ubiquitinated by an exogenously overexpressed ubiquitin ligase, allowing detection of the specific activity of the ubiquitin ligase and isolation of its substrates. Although the diGly antibody enabled effective identification of ubiquitinated proteins in cells, overexpression of an ubiquitin ligase and treatment with a proteasome inhibitor did not increase the level of diGly peptides specific for the ligase relative to the background level of diGly peptides, probably due to deubiquitination. By contrast, in TR-TUBE–expressing cells, the level of substrate-derived diGly peptides produced by the overexpressed ubiquitin ligase was significantly elevated. We developed a method for identifying the substrates of specific ubiquitin ligases using two enrichment strategies, TR-TUBE and diGly remnant antibodies, coupled with MS. Using this method, we identified target substrates of FBXO21, an uncharacterized F-box protein.
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Ibarra, Rebeca, Heather R. Borror, Bryce Hart, Richard G. Gardner, and Gary Kleiger. "The San1 Ubiquitin Ligase Avidly Recognizes Misfolded Proteins through Multiple Substrate Binding Sites." Biomolecules 11, no. 11 (November 2, 2021): 1619. http://dx.doi.org/10.3390/biom11111619.
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Cellular homeostasis depends on robust protein quality control (PQC) pathways that discern misfolded proteins from functional ones in the cell. One major branch of PQC involves the controlled degradation of misfolded proteins by the ubiquitin-proteasome system. Here ubiquitin ligases must recognize and bind to misfolded proteins with sufficient energy to form a complex and with an adequate half-life to achieve poly-ubiquitin chain formation, the signal for protein degradation, prior to its dissociation from the ligase. It is not well understood how PQC ubiquitin ligases accomplish these tasks. Employing a fully reconstituted enzyme and substrate system to perform quantitative biochemical experiments, we demonstrate that the yeast PQC ubiquitin ligase San1 contains multiple substrate binding sites along its polypeptide chain that appear to display specificity for unique misfolded proteins. The results are consistent with a model where these substrate binding sites enable San1 to bind to misfolded substrates avidly, resulting in high affinity ubiquitin ligase-substrate complexes.
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Sievers, Quinlan, Jessica Gasser, Glenn Cowley, John G. Doench, Eric Fischer, and Benjamin L. Ebert. "Genome-Scale Screen Reveals Genes Required for Lenalidomide-Mediated Degradation of Aiolos By CRL4-CRBN." Blood 128, no. 22 (December 2, 2016): 5139. http://dx.doi.org/10.1182/blood.v128.22.5139.5139.
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Abstract Lenalidomide exerts its therapeutic effects in the malignancy multiple myeloma by facilitating the degradation of the transcription factors Ikaros (IKZF1) and Aiolos (IKZF3) by the CRL4-CRBN E3 ubiquitin ligase. In the following study we utilized a positive selection, genome-scale CRISPR-Cas9 screen in the lenalidomide-sensitive myeloma cell line, MM1S, to further our understanding of the molecular machinery which regulates and is required for lenalidomide-mediated modulation of CRL4-CRBN. The gRNAs demonstrating the greatest enrichment following selection with lenalidomide belong to cereblon, the molecular target of lenalidomide and substrate receptor for the CRL4-CRBN ubiquitin ligase. Additionally, 20 of the top 30 genes highlighted by the screen are implicated in both the positive and negative regulation of cullin-ring ligases (CRLs), emphasizing both the importance of cereblon's E3 ligase function in mediating cell death as well as the equilibrium of forces required for proper function of CRLs. Among these genes were the ubiquitin-donor E2 enzymes UBE2D3 and UBE2G1; despite the relevance of E2s to E3 ligase biology it has been difficult to determine via traditional methods which of the ~35 E2 enzymes are utilized by a given E3 ligase. Here we demonstrate that G1 and D3 fulfill distinct functional roles and cooperate with the CRL4CRBN E3 ligase to ubiquitinate an aiolos reprorter with lysine-48 linkages. In aggregate these findings confirm the power of CRISPR-Cas9 positive selection screening to reveal drug mechanism-of-action and provides a paradigm for the identification and functional characterization of E2-E3 pairings. Disclosures Fischer: Novartis: Consultancy.
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Horn-Ghetko, Daniel, David T. Krist, J. Rajan Prabu, Kheewoong Baek, Monique P. C. Mulder, Maren Klügel, Daniel C. Scott, Huib Ovaa, Gary Kleiger, and Brenda A. Schulman. "Ubiquitin ligation to F-box protein targets by SCF–RBR E3–E3 super-assembly." Nature 590, no. 7847 (February 3, 2021): 671–76. http://dx.doi.org/10.1038/s41586-021-03197-9.
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AbstractE3 ligases are typically classified by hallmark domains such as RING and RBR, which are thought to specify unique catalytic mechanisms of ubiquitin transfer to recruited substrates1,2. However, rather than functioning individually, many neddylated cullin–RING E3 ligases (CRLs) and RBR-type E3 ligases in the ARIH family—which together account for nearly half of all ubiquitin ligases in humans—form E3–E3 super-assemblies3–7. Here, by studying CRLs in the SKP1–CUL1–F-box (SCF) family, we show how neddylated SCF ligases and ARIH1 (an RBR-type E3 ligase) co-evolved to ubiquitylate diverse substrates presented on various F-box proteins. We developed activity-based chemical probes that enabled cryo-electron microscopy visualization of steps in E3–E3 ubiquitylation, initiating with ubiquitin linked to the E2 enzyme UBE2L3, then transferred to the catalytic cysteine of ARIH1, and culminating in ubiquitin linkage to a substrate bound to the SCF E3 ligase. The E3–E3 mechanism places the ubiquitin-linked active site of ARIH1 adjacent to substrates bound to F-box proteins (for example, substrates with folded structures or limited length) that are incompatible with previously described conventional RING E3-only mechanisms. The versatile E3–E3 super-assembly may therefore underlie widespread ubiquitylation.
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Wang, Jinnan, Tianye Zhang, Aizhu Tu, Haoxin Xie, Haichao Hu, Jianping Chen, and Jian Yang. "Genome-Wide Identification and Analysis of APC E3 Ubiquitin Ligase Genes Family in Triticum aestivum." Genes 15, no. 3 (February 21, 2024): 271. http://dx.doi.org/10.3390/genes15030271.
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E3 ubiquitin ligases play a pivotal role in ubiquitination, a crucial post-translational modification process. Anaphase-promoting complex (APC), a large cullin-RING E3 ubiquitin ligase, regulates the unidirectional progression of the cell cycle by ubiquitinating specific target proteins and triggering plant immune responses. Several E3 ubiquitin ligases have been identified owing to advancements in sequencing and annotation of the wheat genome. However, the types and functions of APC E3 ubiquitin ligases in wheat have not been reported. This study identified 14 members of the APC gene family in the wheat genome and divided them into three subgroups (CCS52B, CCS52A, and CDC20) to better understand their functions. Promoter sequence analysis revealed the presence of several cis-acting elements related to hormone and stress responses in the APC E3 ubiquitin ligases in wheat. All identified APC E3 ubiquitin ligase family members were highly expressed in the leaves, and the expression of most genes was induced by the application of methyl jasmonate (MeJA). In addition, the APC gene family in wheat may play a role in plant defense mechanisms. This study comprehensively analyzes APC genes in wheat, laying the groundwork for future research on the function of APC genes in response to viral infections and expanding our understanding of wheat immunity mechanisms.
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Saravanan, Konda Mani, Muthu Kannan, Prabhakar Meera, Nagaraj Bharathkumar, and Thirunavukarasou Anand. "E3 ligases: a potential multi-drug target for different types of cancers and neurological disorders." Future Medicinal Chemistry 14, no. 3 (January 2022): 187–201. http://dx.doi.org/10.4155/fmc-2021-0157.
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Ubiquitylation is a posttranslational modification of proteins that is necessary for a variety of cellular processes. E1 ubiquitin activating enzyme, E2 ubiquitin conjugating enzyme, and E3 ubiquitin ligase are all involved in transferring ubiquitin to the target substrate to regulate cellular function. The objective of this review is to provide an overview of different aspects of E3 ubiquitin ligases that can lead to major biological system failure in several deadly diseases. The first part of this review covers the important characteristics of E3 ubiquitin ligases and their classification based on structural domains. Further, the authors provide some online resources that help researchers explore the data relevant to the enzyme. The following section delves into the involvement of E3 ubiquitin ligases in various diseases and biological processes, including different types of cancer and neurological disorders.
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Bhaduri, Utsa, and Giuseppe Merla. "Ubiquitination, Biotech Startups, and the Future of TRIM Family Proteins: A TRIM-Endous Opportunity." Cells 10, no. 5 (April 25, 2021): 1015. http://dx.doi.org/10.3390/cells10051015.
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Ubiquitination is a post-translational modification that has pivotal roles in protein degradation and diversified cellular processes, and for more than two decades it has been a subject of interest in the biotech or biopharmaceutical industry. Tripartite motif (TRIM) family proteins are known to have proven E3 ubiquitin ligase activities and are involved in a multitude of cellular and physiological events and pathophysiological conditions ranging from cancers to rare genetic disorders. Although in recent years many kinds of E3 ubiquitin ligases have emerged as the preferred choices of big pharma and biotech startups in the context of protein degradation and disease biology, from a surface overview it appears that TRIM E3 ubiquitin ligases are not very well recognized yet in the realm of drug discovery. This article will review some of the blockbuster scientific discoveries and technological innovations from the world of ubiquitination and E3 ubiquitin ligases that have impacted the biopharma community, from biotech colossuses to startups, and will attempt to evaluate the future of TRIM family proteins in the province of E3 ubiquitin ligase-based drug discovery.
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Rothweiler, Elisabeth M., Paul E. Brennan, and Kilian V. M. Huber. "Covalent fragment-based ligand screening approaches for identification of novel ubiquitin proteasome system modulators." Biological Chemistry 403, no. 4 (February 23, 2022): 391–402. http://dx.doi.org/10.1515/hsz-2021-0396.
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Abstract Ubiquitination is a key regulatory mechanism vital for maintenance of cellular homeostasis. Protein degradation is induced by E3 ligases via attachment of ubiquitin chains to substrates. Pharmacological exploitation of this phenomenon via targeted protein degradation (TPD) can be achieved with molecular glues or bifunctional molecules facilitating the formation of ternary complexes between an E3 ligase and a given protein of interest (POI), resulting in ubiquitination of the substrate and subsequent proteolysis by the proteasome. Recently, the development of novel covalent fragment screening approaches has enabled the identification of first-in-class ligands for E3 ligases and deubiquitinases revealing so far unexplored binding sites which highlights the potential of these methods to uncover and expand druggable space for new target classes.
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Sung, George. "Similar but Different: RBR E3 Ligases and their Domains that are Crucial for Function." McGill Science Undergraduate Research Journal 12, no. 1 (April 9, 2017): 50–53. http://dx.doi.org/10.26443/msurj.v12i1.45.
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Background: The E3 ubiquitin ligases can be subdivided into four distinct types (RING, HECT, U-box, and RBR type) based on their domain architecture and ubiquitin transfer mechanism. Recent structures of different RBR E3 ligases have been solved showing enzymes in their autoinhibited state. The only exception is HOIP/ HOIL-1L which was recently solved in its “active” conformation. This review discusses the structural and functional characteristics of three different members of the RBR E3 ubiquitin ligase family: Parkin, HOIP/HOIL-1L, and HHARI. Methods: Searches were performed using PubMed. Search term includes “RBR E3 Ligase”, “Parkin”, “HOIP/ HOIL-1L”, “HHARI”, “UbcH7”, and “E2”. In the end, 25 journal articles were selected as the foundation of this review. The structural coordinates of Parkin, HOIP, and HHARI were accessed from the PDB (www.rcsb.org) with the PDB IDs 4ZYN, 5EDV, and 4KBL, respectively. Summary: Currently, most solved RBR E3 ligase structures are only in their inactive forms, except for HOIP/ HOIL-1L, and these inactive forms provide valuable information on how these proteins are regulated in vivo. All the RBR E3 ligases have common domains, but their structures and functions are heavily dependent on their accessory domains, which serve as regulators that orchestrate certain ubiquitin chain syntheses and play a role in the autoinhibition of RBR E3 ligases. Although these domains are structurally different, they use distinct molecular interactions to achieve the same goal. While the regulation of most RBR E3 ligases has been extensively studied, more structural studies are required to further characterize the mechanism that these enzymes use to build different ubiquitin chains. Understanding the mechanisms underlying the formation of each type of ubiquitin chain could help elucidate their functions and related pathways.
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Conway, James A., Grant Kinsman, and Edgar R. Kramer. "The Role of NEDD4 E3 Ubiquitin–Protein Ligases in Parkinson’s Disease." Genes 13, no. 3 (March 14, 2022): 513. http://dx.doi.org/10.3390/genes13030513.
Full textAbstract:
Parkinson’s disease (PD) is a debilitating neurodegenerative disease that causes a great clinical burden. However, its exact molecular pathologies are not fully understood. Whilst there are a number of avenues for research into slowing, halting, or reversing PD, one central idea is to enhance the clearance of the proposed aetiological protein, oligomeric α-synuclein. Oligomeric α-synuclein is the main constituent protein in Lewy bodies and neurites and is considered neurotoxic. Multiple E3 ubiquitin-protein ligases, including the NEDD4 (neural precursor cell expressed developmentally downregulated protein 4) family, parkin, SIAH (mammalian homologues of Drosophila seven in absentia), CHIP (carboxy-terminus of Hsc70 interacting protein), and SCFFXBL5 SCF ubiquitin ligase assembled by the S-phase kinase-associated protein (SKP1), cullin-1 (Cul1), a zinc-binding RING finger protein, and the F-box domain/Leucine-rich repeat protein 5-containing protein FBXL5), have been shown to be able to ubiquitinate α-synuclein, influencing its subsequent degradation via the proteasome or lysosome. Here, we explore the link between NEDD4 ligases and PD, which is not only via α-synuclein but further strengthened by several additional substrates and interaction partners. Some members of the NEDD4 family of ligases are thought to crosstalk even with PD-related genes and proteins found to be mutated in familial forms of PD. Mutations in NEDD4 family genes have not been observed in PD patients, most likely because of their essential survival function during development. Following further in vivo studies, it has been thought that NEDD4 ligases may be viable therapeutic targets in PD. NEDD4 family members could clear toxic proteins, enhancing cell survival and slowing disease progression, or might diminish beneficial proteins, reducing cell survival and accelerating disease progression. Here, we review studies to date on the expression and function of NEDD4 ubiquitin ligases in the brain and their possible impact on PD pathology.
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Rittinger, Katrin. "Ubiquitin-dependent regulation of immune and inflammatory signaling pathways." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C241. http://dx.doi.org/10.1107/s2053273314097587.
Full textAbstract:
Modification of proteins with ubiquitin is a key mechanism for the regulation of a wide range of cellular functions. The outcome of the modification is determined by the way ubiquitin molecules are linked to each other. Linear (M1-linked) ubiquitin chains play an important role in the regulation of immune and inflammatory signaling pathways and contribute to the activation of NF-κB. They are synthesized by the E3 ubiquitin ligase LUBAC (linear ubiquitin chain assembly complex) that is composed of at least three subunits named HOIL-1L, HOIP and SHARPIN. LUBAC belongs to the RBR (RING-inbetween-RING) family of E3 ligases that combine the properties of RING and HECT ligases and act as RING/HECT hybrids. Indeed, we have recently shown that linear ubiquitin chain synthesis proceeds via ubiquitin thioester intermediate formed by the HOIP subunit before subsequent transfer onto the target. I will present a combination of structural and biochemical data that provide a molecular explanation how this unusual E3 ligase complex promotes the synthesis of linear ubiquitin chains with high specificity, regardless of the E2 conjugating enzyme it works with.
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Pu, Zuo-Xian, Jun-Li Wang, Yu-Yang Li, Luo-Yu Liang, Yi-Ting Tan, Ze-Hui Wang, Bao-Lin Li, Guang-Qin Guo, Li Wang, and Lei Wu. "A Bacterial Platform for Studying Ubiquitination Cascades Anchored by SCF-Type E3 Ubiquitin Ligases." Biomolecules 14, no. 10 (September 25, 2024): 1209. http://dx.doi.org/10.3390/biom14101209.
Full textAbstract:
Ubiquitination is one of the most important post-translational modifications in eukaryotes. The ubiquitination cascade includes ubiquitin-activating enzymes (E1), ubiquitin-conjugating enzymes (E2), and ubiquitin ligases (E3). The E3 ligases, responsible for substrate recognition, are the most abundant and varied proteins in the cascade and the most studied. SKP1-CUL1-F-Box (SCF)-type E3 ubiquitin ligases are multi-subunit RING (Really Interesting New Gene) E3 ubiquitin ligases, composed of CUL1 (Cullin 1), RBX1 (RING BOX 1), SKP1 (S-phase Kinase-associated Protein 1), and F-box proteins. In vitro ubiquitination assays, used for studying the specific recognition of substrate proteins by E3 ubiquitin ligases, require the purification of all components involved in the cascade, and for assays with SCF-type E3 ligases, additional proteins (several SCF complex subunits). Here, the Duet expression system was used to co-express E1, E2, ubiquitin, ubiquitylation target (substrate), and the four subunits of a SCF-type E3 ligase in E. coli. When these proteins co-exist in bacterial cells, ubiquitination occurs and can be detected by Western Blot. The effectiveness of this bacterial system for detecting ubiquitination cascade activity was demonstrated by replicating both AtSCFTIR1-mediated and human SCFFBXO28-mediated ubiquitylation in bacteria. This system provides a basic but adaptable platform for the study of SCF-type E3 ubiquitin ligases.
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Zhu, Liguo, Ying Li, Longyuan Zhou, Guang Yang, Ying Wang, Jing Han, Li Li, and Shenghong Zhang. "Role of RING-Type E3 Ubiquitin Ligases in Inflammatory Signalling and Inflammatory Bowel Disease." Mediators of Inflammation 2020 (August 10, 2020): 1–10. http://dx.doi.org/10.1155/2020/5310180.
Full textAbstract:
Ubiquitination is a three-step enzymatic cascade for posttranslational protein modification. It includes the ubiquitin-activating enzyme (E1), ubiquitin-conjugating enzyme (E2), and ubiquitin ligase (E3). RING-type E3 ubiquitin ligases catalyse the posttranslational proteolytic and nonproteolytic functions in various physiological and pathological processes, such as inflammation-associated signal transduction. Resulting from the diversity of substrates and functional mechanisms, RING-type ligases regulate microbe recognition and inflammation by being involved in multiple inflammatory signalling pathways. These processes also occur in autoimmune diseases, especially inflammatory bowel disease (IBD). To understand the importance of RING-type ligases in inflammation, we have discussed their functional mechanisms in multiple inflammation-associated pathways and correlation between RING-type ligases and IBD. Owing to the limited data on the biology of RING-type ligases, there is an urgent need to analyse their potential as biomarkers and therapeutic targets in IBD in the future.
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Giardina, Sarah F., Elena Valdambrini, Michael Peel, Manny D. Bacolod, Mace L. Rothenberg, Richard B. Lanman, J. David Warren, and Francis Barany. "Cure-PROs: Next-generation targeted protein degraders." Journal of Clinical Oncology 41, no. 16_suppl (June 1, 2023): e15101-e15101. http://dx.doi.org/10.1200/jco.2023.41.16_suppl.e15101.
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e15101 Background: Many proteins, including transcription factors and scaffolding proteins, are not amenable to targeting by traditional small molecule inhibitors due to the lack of a well-defined binding pocket or active site. Proteolysis-Targeting Chimeras (PROTACs) are a new class of hetero-bifunctional molecules that bind both a target protein and an E3 ubiquitin ligase, bringing the two into proximity for appending ubiquitin, and subsequently marking the target protein for proteasomal degradation. Currently, thirteen PROTACs are in clinical trials for oncology indications. However, the clinical utility of PROTACs is challenged by their large size and long development timelines. Also, resistance mutations in the E3 ligase or transporter overexpression inevitably evolve. Thus, a new platform for small-molecule degraders that enables ultra-rapid drug development timelines, efficient cellular uptake, and can be developed to overcome innate and acquired drug resistance is needed. Methods: Coferons, developed in our laboratory, are small molecules that self-assemble upon binding to a target, where they form reversible covalent dimers through bio-orthogonal linker chemistries. We have combined features of the Coferon platform and PROTACs to generate CURE-PROs (Combinatorial Ubiquitination REal-time PROteolysis), consisting of one target protein ligand and one E3 ligase ligand that form reversible heterodimers that lead to targeted protein degradation within cells. By modifying known ligands for BRD4, and the E3 ubiquitin ligases Cereblon, VHL, and MDM2, with linkers able to reversibly join the BRD4 to the ligase ligands, we synthesized libraries of CURE-PRO monomers that can be combined to create thousands of CURE-PRO dimer combinations. We explored whether this platform could yield meaningful BRD4 degradation in vitro and in vivo. Results: Rapid combinatorial cell-based screening identified several BRD4-E3 ligase CURE-PRO combinations that induced greater than 50% BRD4 degradation, with the most promising CURE-PRO pairs achieving more than 95% protein degradation. Consistent with a PROTAC mechanism-of-action, successful CURE-PRO combinations confirmed significant protein degradation which was inhibited by proteasome inhibitors or competition with parent ligands. Significant BRD4 degradation was also observed in mice bearing bilateral human xenograft tumors, confirming CURE-PRO proof-of-mechanism in vivo. Conclusions: The combinatorial nature of our platform has the potential to significantly reduce synthesis time and effort to identify the optimal linker length and E3 ligase for each target protein. The CURE-PRO platform consists of expanding libraries of monomers for both additional oncoprotein targets as well as E3 ligases, which can be redeployed to shorten lead development timelines.
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Spratt, Donald E., Helen Walden, and Gary S. Shaw. "RBR E3 ubiquitin ligases: new structures, new insights, new questions." Biochemical Journal 458, no. 3 (February 28, 2014): 421–37. http://dx.doi.org/10.1042/bj20140006.
Full textAbstract:
The RBR (RING-BetweenRING-RING) or TRIAD [two RING fingers and a DRIL (double RING finger linked)] E3 ubiquitin ligases comprise a group of 12 complex multidomain enzymes. This unique family of E3 ligases includes parkin, whose dysfunction is linked to the pathogenesis of early-onset Parkinson's disease, and HOIP (HOIL-1-interacting protein) and HOIL-1 (haem-oxidized IRP2 ubiquitin ligase 1), members of the LUBAC (linear ubiquitin chain assembly complex). The RBR E3 ligases share common features with both the larger RING and HECT (homologous with E6-associated protein C-terminus) E3 ligase families, directly catalysing ubiquitin transfer from an intrinsic catalytic cysteine housed in the C-terminal domain, as well as recruiting thioester-bound E2 enzymes via a RING domain. Recent three-dimensional structures and biochemical findings of the RBRs have revealed novel protein domain folds not previously envisioned and some surprising modes of regulation that have raised many questions. This has required renaming two of the domains in the RBR E3 ligases to more accurately reflect their structures and functions: the C-terminal Rcat (required-for-catalysis) domain, essential for catalytic activity, and a central BRcat (benign-catalytic) domain that adopts the same fold as the Rcat, but lacks a catalytic cysteine residue and ubiquitination activity. The present review discusses how three-dimensional structures of RBR (RING1-BRcat-Rcat) E3 ligases have provided new insights into our understanding of the biochemical mechanisms of these important enzymes in ubiquitin biology.
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Tan, Xu, and Ning Zheng. "Hormone signaling through protein destruction: a lesson from plants." American Journal of Physiology-Endocrinology and Metabolism 296, no. 2 (February 2009): E223—E227. http://dx.doi.org/10.1152/ajpendo.90807.2008.
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Ubiquitin-dependent protein degradation has emerged as a major pathway regulating eukaryotic biology. By employing a variety of ubiquitin ligases to target specific cellular proteins, the ubiquitin-proteasome system controls physiological processes in a highly regulated fashion. Recent studies on a plant hormone auxin have unveiled a novel paradigm of signal transduction in which ubiquitin ligases function as hormone receptors. Perceived by the F-box protein subunit of the SCFTIR1 ubiquitin ligase, auxin directly promotes the recruitment of a family of transcriptional repressors for ubiquitination, thereby activating extensive transcriptional programs. Structural studies have revealed that auxin functions through a “molecular glue” mechanism to enhance protein-protein interactions with the assistance of another small molecule cofactor, inositol hexakisphosphate. Given the extensive repertoire of similar ubiquitin ligases in eukaryotic cells, this novel and widely adopted hormone-signaling mechanism in plants may also exist in other organisms.
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Cooper, Jonathan A., Tomonori Kaneko, and Shawn S. C. Li. "Cell Regulation by Phosphotyrosine-Targeted Ubiquitin Ligases." Molecular and Cellular Biology 35, no. 11 (March 16, 2015): 1886–97. http://dx.doi.org/10.1128/mcb.00098-15.
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Three classes of E3 ubiquitin ligases, members of the Cbl, Hakai, and SOCS-Cul5-RING ligase families, stimulate the ubiquitination of phosphotyrosine-containing proteins, including receptor and nonreceptor tyrosine kinases and their phosphorylated substrates. Because ubiquitination frequently routes proteins for degradation by the lysosome or proteasome, these E3 ligases are able to potently inhibit tyrosine kinase signaling. Their loss or mutational inactivation can contribute to cancer, autoimmunity, or endocrine disorders, such as diabetes. However, these ligases also have biological functions that are independent of their ubiquitination activity. Here we review relevant literature and then focus on more-recent developments in understanding the structures, substrates, and pathways through which the phosphotyrosine-specific ubiquitin ligases regulate diverse aspects of cell biology.
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Zhang, Ting, Yue Xu, Yanfen Liu, and Yihong Ye. "gp78 functions downstream of Hrd1 to promote degradation of misfolded proteins of the endoplasmic reticulum." Molecular Biology of the Cell 26, no. 24 (December 2015): 4438–50. http://dx.doi.org/10.1091/mbc.e15-06-0354.
Full textAbstract:
Eukaryotic cells eliminate misfolded proteins from the endoplasmic reticulum (ER) via a conserved process termed ER-associated degradation (ERAD). Central regulators of the ERAD system are membrane-bound ubiquitin ligases, which are thought to channel misfolded proteins through the ER membrane during retrotranslocation. Hrd1 and gp78 are mammalian ubiquitin ligases homologous to Hrd1p, an ubiquitin ligase essential for ERAD in Saccharomyces cerevisiae. However, the functional relevance of these proteins to Hrd1p is unclear. In this paper, we characterize the gp78-containing ubiquitin ligase complex and define its functional interplay with Hrd1 using biochemical and recently developed CRISPR-based genetic tools. Our data show that transient inactivation of the gp78 complex by short hairpin RNA–mediated gene silencing causes significant stabilization of both luminal and membrane ERAD substrates, but unlike Hrd1, which plays an essential role in retrotranslocation and ubiquitination of these ERAD substrates, knockdown of gp78 does not affect either of these processes. Instead, gp78 appears to act downstream of Hrd1 to promote ERAD via cooperation with the BAG6 chaperone complex. We conclude that the Hrd1 complex forms an essential retrotranslocation module that is evolutionarily conserved, but the mammalian ERAD system uses additional ubiquitin ligases to assist Hrd1 during retrotranslocation.
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Li, Zhongyan, Jingting Wan, Shangfu Li, Yun Tang, Yang-Chi-Dung Lin, Jie Ni, Xiaoxuan Cai, Jinhan Yu, Hsien-Da Huang, and Tzong-Yi Lee. "Multi-Omics Characterization of E3 Regulatory Patterns in Different Cancer Types." International Journal of Molecular Sciences 25, no. 14 (July 11, 2024): 7639. http://dx.doi.org/10.3390/ijms25147639.
Full textAbstract:
Ubiquitination, a post-translational modification, refers to the covalent attachment of ubiquitin molecules to substrates. This modification plays a critical role in diverse cellular processes such as protein degradation. The specificity of ubiquitination for substrates is regulated by E3 ubiquitin ligases. Dysregulation of ubiquitination has been associated with numerous diseases, including cancers. In our study, we first investigated the protein expression patterns of E3 ligases across 12 cancer types. Our findings indicated that E3 ligases tend to be up-regulated and exhibit reduced tissue specificity in tumors. Moreover, the correlation of protein expression between E3 ligases and substrates demonstrated significant changes in cancers, suggesting that E3-substrate specificity alters in tumors compared to normal tissues. By integrating transcriptome, proteome, and ubiquitylome data, we further characterized the E3-substrate regulatory patterns in lung squamous cell carcinoma. Our analysis revealed that the upregulation of the SKP2 E3 ligase leads to excessive degradation of BRCA2, potentially promoting tumor cell proliferation and metastasis. Furthermore, the upregulation of E3 ubiquitin–protein ligase TRIM33 was identified as a biomarker associated with a favorable prognosis by inhibiting the cell cycle. This work exemplifies how leveraging multi-omics data to analyze E3 ligases across various cancers can unveil prognosis biomarkers and facilitate the identification of potential drug targets for cancer therapy.
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Fredrickson, Eric K., Joel C. Rosenbaum, Melissa N. Locke, Thomas I. Milac, and Richard G. Gardner. "Exposed hydrophobicity is a key determinant of nuclear quality control degradation." Molecular Biology of the Cell 22, no. 13 (July 2011): 2384–95. http://dx.doi.org/10.1091/mbc.e11-03-0256.
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Protein quality control (PQC) degradation protects the cell by preventing the toxic accumulation of misfolded proteins. In eukaryotes, PQC degradation is primarily achieved by ubiquitin ligases that attach ubiquitin to misfolded proteins for proteasome degradation. To function effectively, PQC ubiquitin ligases must distinguish misfolded proteins from their normal counterparts by recognizing an attribute of structural abnormality commonly shared among misfolded proteins. However, the nature of the structurally abnormal feature recognized by most PQC ubiquitin ligases is unknown. Here we demonstrate that the yeast nuclear PQC ubiquitin ligase San1 recognizes exposed hydrophobicity in its substrates. San1 recognition is triggered by exposure of as few as five contiguous hydrophobic residues, which defines the minimum window of hydrophobicity required for San1 targeting. We also find that the exposed hydrophobicity recognized by San1 can cause aggregation and cellular toxicity, underscoring the fundamental protective role for San1-mediated PQC degradation of misfolded nuclear proteins.
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Lukashchuk, Natalia, and Karen H. Vousden. "Ubiquitination and Degradation of Mutant p53." Molecular and Cellular Biology 27, no. 23 (October 1, 2007): 8284–95. http://dx.doi.org/10.1128/mcb.00050-07.
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ABSTRACT While wild-type p53 is normally a rapidly degraded protein, mutant forms of p53 are stabilized and accumulate to high levels in tumor cells. In this study, we show that mutant and wild-type p53 proteins are ubiquitinated and degraded through overlapping but distinct pathways. While Mdm2 can drive the degradation of both mutant and wild-type p53, our data suggest that the ability of Mdm2 to function as a ubiquitin ligase is less important in the degradation of mutant p53, which is heavily ubiquitinated in an Mdm2-independent manner. Our initial attempts to identify ubiquitin ligases that are responsible for the ubiquitination of mutant p53 have suggested a role for the chaperone-associated ubiquitin ligase CHIP (C terminus of Hsc70-interacting protein), although other unidentified ubiquitin ligases also appear to contribute. The contribution of Mdm2 to the degradation of mutant p53 may reflect the ability of Mdm2 to deliver the ubiquitinated mutant p53 to the proteasome.
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Mintis, Dimitris G., Anastasia Chasapi, Konstantinos Poulas, George Lagoumintzis, and Christos T. Chasapis. "Assessing the Direct Binding of Ark-Like E3 RING Ligases to Ubiquitin and Its Implication on Their Protein Interaction Network." Molecules 25, no. 20 (October 19, 2020): 4787. http://dx.doi.org/10.3390/molecules25204787.
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The ubiquitin pathway required for most proteins’ targeted degradation involves three classes of enzymes: E1-activating enzyme, E2-conjugating enzyme, and E3-ligases. The human Ark2C is the single known E3 ligase that adopts an alternative, Ub-dependent mechanism for the activation of Ub transfer in the pathway. Its RING domain binds both E2-Ub and free Ub with high affinity, resulting in a catalytic active UbR-RING-E2-UbD complex formation. We examined potential changes in the conformational plasticity of the Ark2C RING domain and its ligands in their complexed form within the ubiquitin pathway through molecular dynamics (MD). Three molecular mechanics force fields compared to previous NMR relaxation studies of RING domain of Arkadia were used for effective and accurate assessment of MDs. Our results suggest the Ark2C Ub-RING docking site has a substantial impact on maintaining the conformational rigidity of E2-E3 assembly, necessary for the E3’s catalytic activity. In the UbR-RING-E2-UbD catalytic complex, the UbR molecule was found to have greater mobility than the other Ub, bound to E2. Furthermore, network-based bioinformatics helped us identify E3 RING ligase candidates which potentially exhibit similar structural modules as Ark2C, along with predicted substrates targeted by the Ub-binding RING Ark2C. Our findings could trigger a further exploration of related unrevealed functions of various other E3 RING ligases.
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Fuseya, Yasuhiro, and Kazuhiro Iwai. "Biochemistry, Pathophysiology, and Regulation of Linear Ubiquitination: Intricate Regulation by Coordinated Functions of the Associated Ligase and Deubiquitinase." Cells 10, no. 10 (October 9, 2021): 2706. http://dx.doi.org/10.3390/cells10102706.
Full textAbstract:
The ubiquitin system modulates protein functions by decorating target proteins with ubiquitin chains in most cases. Several types of ubiquitin chains exist, and chain type determines the mode of regulation of conjugated proteins. LUBAC is a ubiquitin ligase complex that specifically generates N-terminally Met1-linked linear ubiquitin chains. Although linear ubiquitin chains are much less abundant than other types of ubiquitin chains, they play pivotal roles in cell survival, proliferation, the immune response, and elimination of bacteria by selective autophagy. Because linear ubiquitin chains regulate inflammatory responses by controlling the proinflammatory transcription factor NF-κB and programmed cell death (including apoptosis and necroptosis), abnormal generation of linear chains can result in pathogenesis. LUBAC consists of HOIP, HOIL-1L, and SHARPIN; HOIP is the catalytic center for linear ubiquitination. LUBAC is unique in that it contains two different ubiquitin ligases, HOIP and HOIL-1L, in the same ligase complex. Furthermore, LUBAC constitutively interacts with the deubiquitinating enzymes (DUBs) OTULIN and CYLD, which cleave linear ubiquitin chains generated by LUBAC. In this review, we summarize the current status of linear ubiquitination research, and we discuss the intricate regulation of LUBAC-mediated linear ubiquitination by coordinate function of the HOIP and HOIL-1L ligases and OTULIN. Furthermore, we discuss therapeutic approaches to targeting LUBAC-mediated linear ubiquitin chains.
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Ren, Jihui, Younghoon Kee, Jon M. Huibregtse, and Robert C. Piper. "Hse1, a Component of the Yeast Hrs-STAM Ubiquitin-sorting Complex, Associates with Ubiquitin Peptidases and a Ligase to Control Sorting Efficiency into Multivesicular Bodies." Molecular Biology of the Cell 18, no. 1 (January 2007): 324–35. http://dx.doi.org/10.1091/mbc.e06-06-0557.
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Ubiquitinated integral membrane proteins are delivered to the interior of the lysosome/vacuole for degradation. This process relies on specific ubiquitination of potential cargo and recognition of that Ub-cargo by sorting receptors at multiple compartments. We show that the endosomal Hse1-Vps27 sorting receptor binds to ubiquitin peptidases and the ubiquitin ligase Rsp5. Hse1 is linked to Rsp5 directly via a PY element within its C-terminus and through a novel protein Hua1, which recruits a complex of Rsp5, Rup1, and Ubp2. The SH3 domain of Hse1 also binds to the deubiquitinating protein Ubp7. Functional analysis shows that when both modes of Rsp5 association with Hse1 are altered, sorting of cargo that requires efficient ubiquitination for entry into the MVB is blocked, whereas sorting of cargo containing an in-frame addition of ubiquitin is normal. Further deletion of Ubp7 restores sorting of cargo when the Rsp5:Hse1 interaction is compromised suggesting that both ubiquitin ligases and peptidases associate with the Hse1-Vps27 sorting complex to control the ubiquitination status and sorting efficiency of cargo proteins. Additionally, we find that disruption of UBP2 and RUP1 inhibits MVB sorting of some cargos suggesting that Rsp5 requires association with Ubp2 to properly ubiquitinate cargo for efficient MVB sorting.
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Antoniou, Nikolaos, Nefeli Lagopati, Dimitrios Ilias Balourdas, Michail Nikolaou, Alexandros Papalampros, Panagiotis V. S. Vasileiou, Vassilios Myrianthopoulos, et al. "The Role of E3, E4 Ubiquitin Ligase (UBE4B) in Human Pathologies." Cancers 12, no. 1 (December 24, 2019): 62. http://dx.doi.org/10.3390/cancers12010062.
Full textAbstract:
The genome is exposed daily to many deleterious factors. Ubiquitination is a mechanism that regulates several crucial cellular functions, allowing cells to react upon various stimuli in order to preserve their homeostasis. Ubiquitin ligases act as specific regulators and actively participate among others in the DNA damage response (DDR) network. UBE4B is a newly identified member of E3 ubiquitin ligases that appears to be overexpressed in several human neoplasms. The aim of this review is to provide insights into the role of UBE4B ubiquitin ligase in DDR and its association with p53 expression, shedding light particularly on the molecular mechanisms of carcinogenesis.
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Kelsall, Ian R., Jiazhen Zhang, Axel Knebel, J. Simon C. Arthur, and Philip Cohen. "The E3 ligase HOIL-1 catalyses ester bond formation between ubiquitin and components of the Myddosome in mammalian cells." Proceedings of the National Academy of Sciences 116, no. 27 (June 17, 2019): 13293–98. http://dx.doi.org/10.1073/pnas.1905873116.
Full textAbstract:
The linear ubiquitin assembly complex (LUBAC) comprises 3 components: HOIP, HOIL-1, and Sharpin, of which HOIP and HOIL-1 are both members of the RBR subfamily of E3 ubiquitin ligases. HOIP catalyses the formation of Met1-linked ubiquitin oligomers (also called linear ubiquitin), but the function of the E3 ligase activity of HOIL-1 is unknown. Here, we report that HOIL-1 is an atypical E3 ligase that forms oxyester bonds between the C terminus of ubiquitin and serine and threonine residues in its substrates. Exploiting the sensitivity of HOIL-1–generated oxyester bonds to cleavage by hydroxylamine, and macrophages from knock-in mice expressing the E3 ligase-inactive HOIL-1[C458S] mutant, we identify IRAK1, IRAK2, and MyD88 as physiological substrates of the HOIL-1 E3 ligase during Toll-like receptor signaling. HOIL-1 is a monoubiquitylating E3 ubiquitin ligase that initiates the de novo synthesis of polyubiquitin chains that are attached to these proteins in macrophages. HOIL-1 also catalyses its own monoubiquitylation in cells and most probably the monoubiquitylation of Sharpin, in which ubiquitin is also attached by an oxyester bond. Our study establishes that oxyester-linked ubiquitylation is used as an intracellular signaling mechanism.
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Cabana, Valérie C., and Marc P. Lussier. "From Drosophila to Human: Biological Function of E3 Ligase Godzilla and Its Role in Disease." Cells 11, no. 3 (January 23, 2022): 380. http://dx.doi.org/10.3390/cells11030380.
Full textAbstract:
The ubiquitin–proteasome system is of fundamental importance in all fields of biology due to its impact on proteostasis and in regulating cellular processes. Ubiquitination, a type of protein post-translational modification, involves complex enzymatic machinery, such as E3 ubiquitin ligases. The E3 ligases regulate the covalent attachment of ubiquitin to a target protein and are involved in various cellular mechanisms, including the cell cycle, cell division, endoplasmic reticulum stress, and neurotransmission. Because the E3 ligases regulate so many physiological events, they are also associated with pathologic conditions, such as cancer, neurological disorders, and immune-related diseases. This review focuses specifically on the protease-associated transmembrane-containing the Really Interesting New Gene (RING) subset of E3 ligases. We describe the structure, partners, and physiological functions of the Drosophila Godzilla E3 ligase and its human homologues, RNF13, RNF167, and ZNRF4. Also, we summarize the information that has emerged during the last decade regarding the association of these E3 ligases with pathophysiological conditions, such as cancer, asthma, and rare genetic disorders. We conclude by highlighting the limitations of the current knowledge and pinpointing the unresolved questions relevant to RNF13, RNF167, and ZNRF4 ubiquitin ligases.
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Márquez-Cantudo, Laura, Ana Ramos, Claire Coderch, and Beatriz de Pascual-Teresa. "Proteasomal Degradation of Zn-Dependent Hdacs: The E3-Ligases Implicated and the Designed Protacs that Enable Degradation." Molecules 26, no. 18 (September 15, 2021): 5606. http://dx.doi.org/10.3390/molecules26185606.
Full textAbstract:
Protein degradation by the Ubiquitin-Proteasome System is one of the main mechanisms of the regulation of cellular proteostasis, and the E3 ligases are the key effectors for the protein recognition and degradation. Many E3 ligases have key roles in cell cycle regulation, acting as checkpoints and checkpoint regulators. One of the many important proteins involved in the regulation of the cell cycle are the members of the Histone Deacetylase (HDAC) family. The importance of zinc dependent HDACs in the regulation of chromatin packing and, therefore, gene expression, has made them targets for the design and synthesis of HDAC inhibitors. However, achieving potency and selectivity has proven to be a challenge due to the homology between the zinc dependent HDACs. PROteolysis TArgeting Chimaera (PROTAC) design has been demonstrated to be a useful strategy to inhibit and selectively degrade protein targets. In this review, we attempt to summarize the E3 ligases that naturally ubiquitinate HDACs, analyze their structure, and list the known ligands that can bind to these E3 ligases and be used for PROTAC design, as well as the already described HDAC-targeted PROTACs.
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Wei, Wei, Jian-ye Chen, Ze-xiang Zeng, Jian-fei Kuang, Wang-jin Lu, and Wei Shan. "The Ubiquitin E3 Ligase MaLUL2 Is Involved in High Temperature-Induced Green Ripening in Banana Fruit." International Journal of Molecular Sciences 21, no. 24 (December 9, 2020): 9386. http://dx.doi.org/10.3390/ijms21249386.
Full textAbstract:
Harvested banana fruit ripened under warm temperatures above 24 °C remain green peel, leading to severe economic loss. E3 ubiquitin-ligases, as the major components in the ubiquitination pathway, have been implicated to play important roles in temperature-stress responses. However, the molecular mechanism underlying high temperature-triggered stay-green ripening bananas in association with E3 ubiquitin-ligases, remains largely unknown. In this study, a RING-type E3 ubiquitin ligase termed MaLUL2, was isolated and characterized from banana fruit. The MaLUL2 gene contains 1095 nucleotides and encodes a protein with 365 amino acids. The MaLUL2 protein contains a domain associated with RING2 (DAR2) and a RING domain, which are the typical characteristics of RING-type E3 ligases. MaLUL2 expression was up-regulated during high temperature-induced green ripening. Subcellular localization showed that MaLUL2 localized in the nucleus, cytoplasm, and plasma membrane. MaLUL2 displayed E3 ubiquitin ligase activity in vitro. More importantly, transient overexpression of MaLUL2 in banana fruit peel increased the level of ubiquitination in vivo and led to a stay-green phenotype, accompanying with decreased expression of chlorophyll catabolic genes. Collectively, these findings suggest that MaLUL2 might act as a negative regulator of chlorophyll degradation and provide novel insights into the regulatory mechanism of high temperature-induced green ripening bananas.
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Palomba, Tommaso, Giusy Tassone, Carmine Vacca, Matteo Bartalucci, Aurora Valeri, Cecilia Pozzi, Simon Cross, Lydia Siragusa, and Jenny Desantis. "Exploiting ELIOT for Scaffold-Repurposing Opportunities: TRIM33 a Possible Novel E3 Ligase to Expand the Toolbox for PROTAC Design." International Journal of Molecular Sciences 23, no. 22 (November 17, 2022): 14218. http://dx.doi.org/10.3390/ijms232214218.
Full textAbstract:
The field of targeted protein degradation, through the control of the ubiquitin–proteasome system (UPS), is progressing considerably; to exploit this new therapeutic modality, the proteolysis targeting chimera (PROTAC) technology was born. The opportunity to use PROTACs engaging of new E3 ligases that can hijack and control the UPS system could greatly extend the applicability of degrading molecules. To this end, here we show a potential application of the ELIOT (E3 LIgase pocketOme navigaTor) platform, previously published by this group, for a scaffold-repurposing strategy to identify new ligands for a novel E3 ligase, such as TRIM33. Starting from ELIOT, a case study of the cross-relationship using GRID Molecular Interaction Field (MIF) similarities between TRIM24 and TRIM33 binding sites was selected. Based on the assumption that similar pockets could bind similar ligands and considering that TRIM24 has 12 known co-crystalised ligands, we applied a scaffold-repurposing strategy for the identification of TRIM33 ligands exploiting the scaffold of TRIM24 ligands. We performed a deeper computational analysis to identify pocket similarities and differences, followed by docking and water analysis; selected ligands were synthesised and subsequently tested against TRIM33 via HTRF binding assay, and we obtained the first-ever X-ray crystallographic complexes of TRIM33α with three of the selected compounds.
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Toma-Fukai, Sachiko, and Toshiyuki Shimizu. "Structural Diversity of Ubiquitin E3 Ligase." Molecules 26, no. 21 (November 4, 2021): 6682. http://dx.doi.org/10.3390/molecules26216682.
Full textAbstract:
The post-translational modification of proteins regulates many biological processes. Their dysfunction relates to diseases. Ubiquitination is one of the post-translational modifications that target lysine residue and regulate many cellular processes. Three enzymes are required for achieving the ubiquitination reaction: ubiquitin-activating enzyme (E1), ubiquitin-conjugating enzyme (E2), and ubiquitin ligase (E3). E3s play a pivotal role in selecting substrates. Many structural studies have been conducted to reveal the molecular mechanism of the ubiquitination reaction. Recently, the structure of PCAF_N, a newly categorized E3 ligase, was reported. We present a review of the recent progress toward the structural understanding of E3 ligases.
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Oswald, Jessica, Mathew Constantine, Adedolapo Adegbuyi, Esosa Omorogbe, Anna J. Dellomo, and Elana S. Ehrlich. "E3 Ubiquitin Ligases in Gammaherpesviruses and HIV: A Review of Virus Adaptation and Exploitation." Viruses 15, no. 9 (September 15, 2023): 1935. http://dx.doi.org/10.3390/v15091935.
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For productive infection and replication to occur, viruses must control cellular machinery and counteract restriction factors and antiviral proteins. Viruses can accomplish this, in part, via the regulation of cellular gene expression and post-transcriptional and post-translational control. Many viruses co-opt and counteract cellular processes via modulation of the host post-translational modification machinery and encoding or hijacking kinases, SUMO ligases, deubiquitinases, and ubiquitin ligases, in addition to other modifiers. In this review, we focus on three oncoviruses, Epstein–Barr virus (EBV), Kaposi’s sarcoma herpesvirus (KSHV), and human immunodeficiency virus (HIV) and their interactions with the ubiquitin–proteasome system via viral-encoded or cellular E3 ubiquitin ligase activity.
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Zeng, Ruiyin, Yuan Xiong, Ze Lin, Adriana C. Panayi, Yun Sun, Faqi Cao, and Guohui Liu. "E3 Ubiquitin Ligases: Potential Therapeutic Targets for Skeletal Pathology and Degeneration." Stem Cells International 2022 (September 27, 2022): 1–13. http://dx.doi.org/10.1155/2022/6948367.
Full textAbstract:
The ubiquitination-proteasome system (UPS) is crucial in regulating a variety of cellular processes including proliferation, differentiation, and survival. Ubiquitin protein ligase E3 is the most critical molecule in the UPS system. Dysregulation of the UPS system is associated with many conditions. Over the past few decades, there have been an increasing number of studies focusing on the UPS system and how it affects bone metabolism. Multiple E3 ubiquitin ligases have been found to mediate osteogenesis or osteolysis through a variety of pathways. In this review, we describe the mechanisms of UPS, especially E3 ubiquitin ligases on bone metabolism. To date, many E3 ubiquitin ligases have been found to regulate osteogenesis or osteoclast differentiation. We review the classification of these E3 enzymes and the mechanisms that influence upstream and downstream molecules and transduction pathways. Finally, this paper reviews the discovery of the relevant UPS inhibitors, drug molecules, and noncoding RNAs so far and prospects the future research and treatment.
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Fukumoto, Yasunori, Naoshi Dohmae, and Fumio Hanaoka. "Schizosaccharomyces pombe Ddb1 Recruits Substrate-Specific Adaptor Proteins through a Novel Protein Motif, the DDB-Box." Molecular and Cellular Biology 28, no. 22 (September 15, 2008): 6746–56. http://dx.doi.org/10.1128/mcb.00757-08.
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ABSTRACT DDB1 was isolated as a UV-damaged DNA-binding protein, but recent studies established that it plays a role as a component of cullin 4A ubiquitin ligases. Cullin-RING complexes are the largest known ubiquitin ligase family, with hundreds of substrate-specific adaptor subunits and which are defined by characteristic motifs. A common motif for DDB1/cullin 4 ubiquitin ligases, a WDXR motif, was recently reported. Here, we show that Schizosaccharomyces pombe Ddb1 associates with several WD40 repeat proteins that share a novel protein motif designated the DDB-box, a motif essential for interaction with Ddb1 and independent of WD40 repeats, unlike the WDXR motif. We also show that ddb1 + and the putative CSA homolog ckn1 + are involved in transcription-coupled nucleotide excision repair and that the DDB-box is essential for the ckn1 + function in vivo. These data indicate that the DDB-box is another common motif which defines adaptor proteins for DDB1/cullin 4 ubiquitin ligases.
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Medvar, Barbara, Viswanathan Raghuram, Trairak Pisitkun, Abhijit Sarkar, and Mark A. Knepper. "Comprehensive database of human E3 ubiquitin ligases: application to aquaporin-2 regulation." Physiological Genomics 48, no. 7 (July 1, 2016): 502–12. http://dx.doi.org/10.1152/physiolgenomics.00031.2016.
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Aquaporin-2 (AQP2) is regulated in part via vasopressin-mediated changes in protein half-life that are in turn dependent on AQP2 ubiquitination. Here we addressed the question, “What E3 ubiquitin ligase is most likely to be responsible for AQP2 ubiquitination?” using large-scale data integration based on Bayes' rule. The first step was to bioinformatically identify all E3 ligase genes coded by the human genome. The 377 E3 ubiquitin ligases identified in the human genome, consisting predominant of HECT, RING, and U-box proteins, have been used to create a publically accessible and downloadable online database ( https://hpcwebapps.cit.nih.gov/ESBL/Database/E3-ligases/ ). We also curated a second database of E3 ligase accessory proteins that included BTB domain proteins, cullins, SOCS-box proteins, and F-box proteins. Using Bayes' theorem to integrate information from multiple large-scale proteomic and transcriptomic datasets, we ranked these 377 E3 ligases with respect to their probability of interaction with AQP2. Application of Bayes' rule identified the E3 ligases most likely to interact with AQP2 as (in order of probability): NEDD4 and NEDD4L (tied for first), AMFR, STUB1, ITCH, ZFPL1. Significantly, the two E3 ligases tied for top rank have also been studied extensively in the reductionist literature as regulatory proteins in renal tubule epithelia. The concordance of conclusions from reductionist and systems-level data provides strong motivation for further studies of the roles of NEDD4 and NEDD4L in the regulation of AQP2 protein turnover.
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Kolesar, Peter, Karel Stejskal, David Potesil, Johanne M. Murray, and Jan J. Palecek. "Role of Nse1 Subunit of SMC5/6 Complex as a Ubiquitin Ligase." Cells 11, no. 1 (January 4, 2022): 165. http://dx.doi.org/10.3390/cells11010165.
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Structural Maintenance of Chromosomes (SMC) complexes are important for many aspects of the chromosomal organization. Unlike cohesin and condensin, the SMC5/6 complex contains a variant RING domain carried by its Nse1 subunit. RING domains are characteristic for ubiquitin ligases, and human NSE1 has been shown to possess ubiquitin-ligase activity in vitro. However, other studies were unable to show such activity. Here, we confirm Nse1 ubiquitin-ligase activity using purified Schizosaccharomyces pombe proteins. We demonstrate that the Nse1 ligase activity is stimulated by Nse3 and Nse4. We show that Nse1 specifically utilizes Ubc13/Mms2 E2 enzyme and interacts directly with ubiquitin. We identify the Nse1 mutation (R188E) that specifically disrupts its E3 activity and demonstrate that the Nse1-dependent ubiquitination is particularly important under replication stress. Moreover, we determine Nse4 (lysine K181) as the first known SMC5/6-associated Nse1 substrate. Interestingly, abolition of Nse4 modification at K181 leads to suppression of DNA-damage sensitivity of other SMC5/6 mutants. Altogether, this study brings new evidence for Nse1 ubiquitin ligase activity, significantly advancing our understanding of this enigmatic SMC5/6 function.
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Zhang, Gui, Yunfang Zhang, Luxuan Chen, Langxia Liu, and Xuejuan Gao. "E3 ubiquitin ligase-dependent regulatory mechanism of TRIM family in carcinogenesis." Cancer Insight 2, no. 1 (June 28, 2023): 102–30. http://dx.doi.org/10.58567/ci02010007.
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Tripartite motif-containing (TRIM) proteins consist of over 80 proteins, the majority of which exhibit E3 ubiquitin ligase activity. E3 ligases have a critical role in various cellular processes by specifically recognizing and ubiquitinating substrate proteins to promote their proteasomal degradation or alter their activities. Numerous studies have indicated that TRIMs are involved in carcinogenesis through various mechanisms. However, the regulatory mechanisms delimitating TRIMs’ function as E3 ligases has not yet been specifically addressed in a previous review article. In this review, we focus on recent advancements in understanding how certain TRIMs function solely as E3 ligases during cancer cell proliferation, apoptosis, and metastasis. We comprehensively summarize the target proteins of TRIMs involved in disordered signaling pathways such as Wnt/β-catenin, PI3K/AKT, NF-κB, p53, ERK, and STAT3, as well as those regulating the cell cycle and glycolysis. Following ubiquitination modification by TRIM E3 ligases, these target proteins either undergo proteasome-mediating degradation, maintain steady levels, or get activated/inactivated. This review provides a foundation for the development of E3 ligase-based cancer treatments.