1
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Gu J, Chen C, He P, Du Y, Zhu B. Unraveling the Immune Regulatory Functions of USP5: Implications for Disease Therapy. Biomolecules 2024; 14:683. [PMID: 38927085 PMCID: PMC11201890 DOI: 10.3390/biom14060683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2024] [Revised: 05/30/2024] [Accepted: 06/08/2024] [Indexed: 06/28/2024] Open
Abstract
Ubiquitin-specific protease 5 (USP5) belongs to the ubiquitin-specific protease (USP) family, which uniquely recognizes unanchored polyubiquitin chains to maintain the homeostasis of monoubiquitin chains. USP5 participates in a wide range of cellular processes by specifically cleaving isopeptide bonds between ubiquitin and substrate proteins or ubiquitin itself. In the process of immune regulation, USP5 affects important cellular signaling pathways, such as NF-κB, Wnt/β-catenin, and IFN, by regulating ubiquitin-dependent protein degradation. These pathways play important roles in immune regulation and inflammatory responses. In addition, USP5 regulates the activity and function of immunomodulatory signaling pathways via the deubiquitination of key proteins, thereby affecting the activity of immune cells and the regulation of immune responses. In the present review, the structure and function of USP5, its role in immune regulation, and the mechanism by which USP5 affects the development of diseases by regulating immune signaling pathways are comprehensively overviewed. In addition, we also introduce the latest research progress of targeting USP5 in the treatment of related diseases, calling for an interdisciplinary approach to explore the therapeutic potential of targeting USP5 in immune regulation.
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Affiliation(s)
- Jinyi Gu
- Institute of Pathogen Biology, School of Basic Medical Sciences, Lanzhou University, Lanzhou 730030, China; (J.G.); (P.H.); (Y.D.)
- Gansu Provincial Key Laboratory of Evidence Based Medicine and Clinical Translation, Lanzhou 730030, China
- Clinical Laboratory, Affiliated Hospital of Yunnan University, Kunming 650032, China
| | - Changshun Chen
- Department of Orthopedics, Lanzhou University Second Hospital, Lanzhou 730030, China;
- Department of Orthopedics and Trauma Surgery, Affiliated Hospital of Yunnan University, Kunming 650032, China
| | - Pu He
- Institute of Pathogen Biology, School of Basic Medical Sciences, Lanzhou University, Lanzhou 730030, China; (J.G.); (P.H.); (Y.D.)
- Gansu Provincial Key Laboratory of Evidence Based Medicine and Clinical Translation, Lanzhou 730030, China
| | - Yunjie Du
- Institute of Pathogen Biology, School of Basic Medical Sciences, Lanzhou University, Lanzhou 730030, China; (J.G.); (P.H.); (Y.D.)
- Gansu Provincial Key Laboratory of Evidence Based Medicine and Clinical Translation, Lanzhou 730030, China
| | - Bingdong Zhu
- Institute of Pathogen Biology, School of Basic Medical Sciences, Lanzhou University, Lanzhou 730030, China; (J.G.); (P.H.); (Y.D.)
- Gansu Provincial Key Laboratory of Evidence Based Medicine and Clinical Translation, Lanzhou 730030, China
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2
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Gao ST, Xin X, Wang ZY, Hu YY, Feng Q. USP5: Comprehensive insights into structure, function, biological and disease-related implications, and emerging therapeutic opportunities. Mol Cell Probes 2024; 73:101944. [PMID: 38049041 DOI: 10.1016/j.mcp.2023.101944] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 11/27/2023] [Accepted: 11/28/2023] [Indexed: 12/06/2023]
Abstract
Ubiquitin specific protease 5 (USP5) is a vital deubiquitinating enzyme that regulates various physiological functions by removing ubiquitin chains from target proteins. This review provides an overview of the structural and functional characteristics of USP5. Additionally, we discuss the role of USP5 in regulating diverse cellular processes, including cell proliferation, apoptosis, DNA double-strand damage, methylation, heat stress, and protein quality control, by targeting different substrates. Furthermore, we describe the involvement of USP5 in several pathological conditions such as tumors, pathological pain, developmental abnormalities, inflammatory diseases, and virus infection. Finally, we introduce newly developed inhibitors of USP5. In conclusion, investigating the novel functions and substrates of USP5, elucidating the underlying mechanisms of USP5-substrate interactions, intensifying the development of inhibitors, and exploring the upstream regulatory mechanisms of USP5 in detail can provide a new theoretical basis for the treatment of various diseases, including cancer, which is a promising research direction with considerable potential. Overall, USP5 plays a critical role in regulating various physiological and pathological processes, and investigating its novel functions and regulatory mechanisms may have significant implications for the development of therapeutic strategies for cancer and other diseases.
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Affiliation(s)
- Si-Ting Gao
- Institute of Liver Diseases, Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Xin Xin
- Key Laboratory of Liver and Kidney Diseases, Shanghai University of Traditional Chinese Medicine, Ministry of Education, Shanghai, China
| | - Zhuo-Yuan Wang
- Institute of Liver Diseases, Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Yi-Yang Hu
- Institute of Liver Diseases, Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai, China; Key Laboratory of Liver and Kidney Diseases, Shanghai University of Traditional Chinese Medicine, Ministry of Education, Shanghai, China; Shanghai Key Laboratory of Traditional Chinese Clinical Medicine, Shanghai, China.
| | - Qin Feng
- Institute of Liver Diseases, Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai, China; Key Laboratory of Liver and Kidney Diseases, Shanghai University of Traditional Chinese Medicine, Ministry of Education, Shanghai, China; Central Laboratory, ShuGuang Hospital Affiliated to Shanghai University of Chinese Traditional Medicine, Shanghai, China; Shanghai Key Laboratory of Traditional Chinese Clinical Medicine, Shanghai, China.
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3
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Pai YL, Lin YJ, Peng WH, Huang LT, Chou HY, Wang CH, Chien CT, Chen GC. The deubiquitinase Leon/USP5 interacts with Atg1/ULK1 and antagonizes autophagy. Cell Death Dis 2023; 14:540. [PMID: 37607937 PMCID: PMC10444890 DOI: 10.1038/s41419-023-06062-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 07/21/2023] [Accepted: 08/14/2023] [Indexed: 08/24/2023]
Abstract
Accumulating evidence has shown that the quality of proteins must be tightly monitored and controlled to maintain cellular proteostasis. Misfolded proteins and protein aggregates are targeted for degradation through the ubiquitin proteasome (UPS) and autophagy-lysosome systems. The ubiquitination and deubiquitinating enzymes (DUBs) have been reported to play pivotal roles in the regulation of the UPS system. However, the function of DUBs in the regulation of autophagy remain to be elucidated. In this study, we found that knockdown of Leon/USP5 caused a marked increase in the formation of autophagosomes and autophagic flux under well-fed conditions. Genetic analysis revealed that overexpression of Leon suppressed Atg1-induced cell death in Drosophila. Immunoblotting assays further showed a strong interaction between Leon/USP5 and the autophagy initiating kinase Atg1/ULK1. Depletion of Leon/USP5 led to increased levels of Atg1/ULK1. Our findings indicate that Leon/USP5 is an autophagic DUB that interacts with Atg1/ULK1, negatively regulating the autophagic process.
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Affiliation(s)
- Yueh-Ling Pai
- Institute of Biological Chemistry, Academia Sinica, Taipei, 115, Taiwan
| | - Yuchieh Jay Lin
- Institute of Biochemical Sciences, College of Life Science, National Taiwan University, Taipei, 106, Taiwan
- Chemical Biology and Molecular Biophysics, Taiwan International Graduate Program, Academia Sinica, Taipei, 115, Taiwan
| | - Wen-Hsin Peng
- Institute of Biological Chemistry, Academia Sinica, Taipei, 115, Taiwan
| | - Li-Ting Huang
- Institute of Biochemical Sciences, College of Life Science, National Taiwan University, Taipei, 106, Taiwan
| | - He-Yen Chou
- Institute of Biological Chemistry, Academia Sinica, Taipei, 115, Taiwan
| | - Chien-Hsiang Wang
- Institute of Molecular Biology, Academia Sinica, Taipei, 115, Taiwan
| | - Cheng-Ting Chien
- Institute of Molecular Biology, Academia Sinica, Taipei, 115, Taiwan
| | - Guang-Chao Chen
- Institute of Biological Chemistry, Academia Sinica, Taipei, 115, Taiwan.
- Institute of Biochemical Sciences, College of Life Science, National Taiwan University, Taipei, 106, Taiwan.
- Chemical Biology and Molecular Biophysics, Taiwan International Graduate Program, Academia Sinica, Taipei, 115, Taiwan.
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4
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Yan B, Guo J, Wang Z, Ning J, Wang H, Shu L, Hu K, Chen L, Shi Y, Zhang L, Liu S, Tao Y, Xiao D. The ubiquitin-specific protease 5 mediated deubiquitination of LSH links metabolic regulation of ferroptosis to hepatocellular carcinoma progression. MedComm (Beijing) 2023; 4:e337. [PMID: 37492786 PMCID: PMC10363799 DOI: 10.1002/mco2.337] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 06/20/2023] [Accepted: 06/26/2023] [Indexed: 07/27/2023] Open
Abstract
Epigenetic regulators and posttranslational modifications of proteins play important roles in various kinds of cancer cell death, including ferroptosis, a non-apoptotic form of cell death. However, the interplay of chromatin modifiers and deubiquitinase (DUB) in ferroptosis remains unclear. Here, we found that ubiquitin-specific protease 5 (USP5) is regarded as a bona fide DUB of lymphoid-specific helicase (LSH), a DNA methylation repressor, in hepatocellular carcinoma (HCC). Functional studies reveal that USP5 interacts with LSH and stabilizes LSH by a deubiquitylation activity-dependent process. Furthermore, the USP5-mediated deubiquitination of LSH facilitates the tumorigenesis of HCC by upregulating solute carrier family 7 member 11 (SLC7A11) to suppress ferroptosis of liver cancer cells. Moreover, the USP5 inhibitor degrasyn inhibits DUB activities of USP5 to LSH to suppress the progression of HCC. Additionally, USP5 and LSH are positively correlated and both are overexpressed and linked to poor prognosis in HCC patients. Together, our findings show that USP5 interacts with LSH directly and enhances LSH protein stability through deubiquitination, which, in turn, promotes the development of HCC by suppressing ferroptosis of liver cancer cells, suggesting that USP5 may be a potential therapeutic target for HCC.
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Affiliation(s)
- Bokang Yan
- Department of PathologyZhuzhou Hospital Affiliated to Xiangya School of MedicineCentral South UniversityZhuzhouHunanChina
- Department of PathologyXiangya HospitalCentral South UniversityChangshaHunanChina
- NHC Key Laboratory of Carcinogenesis (Central South University), Key Laboratory of Carcinogenesis and Cancer Invasion (Ministry of Education)Cancer Research Institute and School of Basic MedicineCentral South UniversityChangshaHunanChina
| | - Jiaxing Guo
- Department of PathologyXiangya HospitalCentral South UniversityChangshaHunanChina
- NHC Key Laboratory of Carcinogenesis (Central South University), Key Laboratory of Carcinogenesis and Cancer Invasion (Ministry of Education)Cancer Research Institute and School of Basic MedicineCentral South UniversityChangshaHunanChina
| | - Zuli Wang
- Department of PathologyXiangya HospitalCentral South UniversityChangshaHunanChina
- NHC Key Laboratory of Carcinogenesis (Central South University), Key Laboratory of Carcinogenesis and Cancer Invasion (Ministry of Education)Cancer Research Institute and School of Basic MedicineCentral South UniversityChangshaHunanChina
| | - Jieling Ning
- NHC Key Laboratory of Carcinogenesis (Central South University), Key Laboratory of Carcinogenesis and Cancer Invasion (Ministry of Education)Cancer Research Institute and School of Basic MedicineCentral South UniversityChangshaHunanChina
| | - Haiyan Wang
- Department of PathologyXiangya HospitalCentral South UniversityChangshaHunanChina
- NHC Key Laboratory of Carcinogenesis (Central South University), Key Laboratory of Carcinogenesis and Cancer Invasion (Ministry of Education)Cancer Research Institute and School of Basic MedicineCentral South UniversityChangshaHunanChina
| | - Long Shu
- NHC Key Laboratory of Carcinogenesis (Central South University), Key Laboratory of Carcinogenesis and Cancer Invasion (Ministry of Education)Cancer Research Institute and School of Basic MedicineCentral South UniversityChangshaHunanChina
| | - Kuan Hu
- NHC Key Laboratory of Carcinogenesis (Central South University), Key Laboratory of Carcinogenesis and Cancer Invasion (Ministry of Education)Cancer Research Institute and School of Basic MedicineCentral South UniversityChangshaHunanChina
- Department of Hepatobiliary SurgeryXiangya HospitalCentral South UniversityChangshaHunanChina
| | - Ling Chen
- Department of PathologyXiangya HospitalCentral South UniversityChangshaHunanChina
- NHC Key Laboratory of Carcinogenesis (Central South University), Key Laboratory of Carcinogenesis and Cancer Invasion (Ministry of Education)Cancer Research Institute and School of Basic MedicineCentral South UniversityChangshaHunanChina
| | - Ying Shi
- Department of PathologyXiangya HospitalCentral South UniversityChangshaHunanChina
- NHC Key Laboratory of Carcinogenesis (Central South University), Key Laboratory of Carcinogenesis and Cancer Invasion (Ministry of Education)Cancer Research Institute and School of Basic MedicineCentral South UniversityChangshaHunanChina
| | - Lingqiang Zhang
- State Key Laboratory of ProteomicsBeijing Proteome Research CenterBeijing Institute of Radiation MedicineCollaborative Innovation Center for Cancer MedicineBeijingChina
| | - Shuang Liu
- Department of OncologyInstitute of Medical SciencesNational Clinical Research Center for Geriatric DisordersXiangya HospitalCentral South UniversityChangshaHunanChina
| | - Yongguang Tao
- Department of PathologyXiangya HospitalCentral South UniversityChangshaHunanChina
- NHC Key Laboratory of Carcinogenesis (Central South University), Key Laboratory of Carcinogenesis and Cancer Invasion (Ministry of Education)Cancer Research Institute and School of Basic MedicineCentral South UniversityChangshaHunanChina
- Department of Thoracic SurgeryHunan Key Laboratory of Early Diagnosis and Precision Therapy in Lung CancerSecond Xiangya HospitalCentral South UniversityChangshaHunanChina
| | - Desheng Xiao
- Department of PathologyXiangya HospitalCentral South UniversityChangshaHunanChina
- Department of PathologySchool of Basic MedicineCentral South UniversityChangshaHunanChina
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5
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Yan B, Guo J, Deng S, Chen D, Huang M. A pan-cancer analysis of the role of USP5 in human cancers. Sci Rep 2023; 13:8972. [PMID: 37268697 DOI: 10.1038/s41598-023-35793-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2023] [Accepted: 05/24/2023] [Indexed: 06/04/2023] Open
Abstract
Posttranslational modifications (PTM) such as acetylation, deubiquitination, and phosphorylation of proteins, play important roles in various kinds of cancer progression. Ubiquitin-specific proteinase 5 (USP5), a unique member of deubiquitinating enzymes (DUBs) which recognizes unanchored polyubiquitin specifically, could regulate the stability of many tumorigenesis-associated proteins to influence cancer initiation and progression. However, the diverse biological significance of USP5 in pan-cancer has not been systematically and comprehensively studied. Here, we explored the role of USP5 in pan-cancer using The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx) database, and we also acquired and analyzed data via various software and web platforms such as R, GEPIA2.0, HPA, TISIDB, cBioPortal, UALCAN, TIMER 2.0, CancerSEA and BioGRID. USP5 expression was high in most cancers and differed significantly in different molecular and immune subtypes of cancers. In addition, USP5 had certain diagnostic value in multiple cancers, and high expression of USP5 generally predicted poor prognosis for cancer patients. We also found that the most frequent genetic alterations type of USP5 was mutation, and the DNA methylation level of USP5 decreased in various cancers. Furthermore, USP5 expression correlated with cancer-associated fibroblasts (CAFs), endothelial cells (EC) and genetic markers of immunodulators in cancers. Moreover, the result from single cell sequencing showed that USP5 could regulate several tumor biological behaviors such as apoptosis, DNA damage and metastasis. Gene enrichment analysis indicated "spliceosome" and "RNA splicing" may be the critical mechanism for USP5 to involve in cancer. Taken together, our study elucidates the biological significance of USP5 in the diagnosis, prognosis and immune in human pan-cancer.
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Affiliation(s)
- Bokang Yan
- Department of Pathology, Zhuzhou Hospital Affiliated to Xiangya School of Medicine, Central South University, Zhuzhou, 412007, Hunan, China
| | - Jiaxing Guo
- Department of Hematology, Zhuzhou Hospital Affiliated to Xiangya School of Medicine, Central South University, Zhuzhou, 412007, Hunan, China
| | - Shuang Deng
- Department of Pathology, Zhuzhou Hospital Affiliated to Xiangya School of Medicine, Central South University, Zhuzhou, 412007, Hunan, China
| | - Dongliang Chen
- Department of Pathology, Zhuzhou Hospital Affiliated to Xiangya School of Medicine, Central South University, Zhuzhou, 412007, Hunan, China.
| | - Meiyuan Huang
- Department of Pathology, Zhuzhou Hospital Affiliated to Xiangya School of Medicine, Central South University, Zhuzhou, 412007, Hunan, China.
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6
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Hayashi T, Tomomizu T, Sushida T, Akiyama M, Ei SI, Sato M. Tiling mechanisms of the Drosophila compound eye through geometrical tessellation. Curr Biol 2022; 32:2101-2109.e5. [PMID: 35390281 DOI: 10.1016/j.cub.2022.03.046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 02/16/2022] [Accepted: 03/15/2022] [Indexed: 11/29/2022]
Abstract
Tiling patterns are observed in many biological structures. The compound eye is an interesting example of tiling and is often constructed by hexagonal arrays of ommatidia, the optical unit of the compound eye. Hexagonal tiling may be common due to mechanical restrictions such as structural robustness, minimal boundary length, and space-filling efficiency. However, some insects exhibit tetragonal facets.1-4 Some aquatic crustaceans, such as shrimp and lobsters, have evolved with tetragonal facets.5-8 Mantis shrimp is an insightful example as its compound eye has a tetragonal midband region sandwiched between hexagonal hemispheres.9,10 This casts doubt on the naive explanation that hexagonal tiles recur in nature because of their mechanical stability. Similarly, tetragonal tiling patterns are also observed in some Drosophila small-eye mutants, whereas the wild-type eyes are hexagonal, suggesting that the ommatidial tiling is not simply explained by such mechanical restrictions. If so, how are the hexagonal and tetragonal patterns controlled during development? Here, we demonstrate that geometrical tessellation determines the ommatidial tiling patterns. In small-eye mutants, the hexagonal pattern is transformed into a tetragonal pattern as the relative positions of neighboring ommatidia are stretched along the dorsal-ventral axis. We propose that the regular distribution of ommatidia and their uniform growth collectively play an essential role in the establishment of tetragonal and hexagonal tiling patterns in compound eyes.
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Affiliation(s)
- Takashi Hayashi
- Mathematical Neuroscience Unit, Institute for Frontier Science Initiative, Kanazawa University, 13-1 Takaramachi, Kanazawa, Ishikawa 920-8640, Japan.
| | - Takeshi Tomomizu
- Graduate School of Frontier Science Initiative, Kanazawa University, 13-1 Takaramachi, Kanazawa, Ishikawa 920-8640, Japan
| | - Takamichi Sushida
- Department of Computer Science and Technology, Salesian Polytechnic, 4-6-8 Oyamagaoka, Machida, Tokyo 194-0215, Japan
| | - Masakazu Akiyama
- Faculty of Science, Academic Assembly, University of Toyama, 3190 Gofuku, Toyama 930-8555, Japan
| | - Shin-Ichiro Ei
- Department of Mathematics, Faculty of Science, Hokkaido University, Kita 10, Nishi 8, Kita-Ku, Sapporo, Hokkaido 060-0810, Japan
| | - Makoto Sato
- Mathematical Neuroscience Unit, Institute for Frontier Science Initiative, Kanazawa University, 13-1 Takaramachi, Kanazawa, Ishikawa 920-8640, Japan.
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7
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Lee CS, Kim S, Hwang G, Song J. Deubiquitinases: Modulators of Different Types of Regulated Cell Death. Int J Mol Sci 2021; 22:4352. [PMID: 33919439 PMCID: PMC8122337 DOI: 10.3390/ijms22094352] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Revised: 04/16/2021] [Accepted: 04/19/2021] [Indexed: 02/06/2023] Open
Abstract
The mechanisms and physiological implications of regulated cell death (RCD) have been extensively studied. Among the regulatory mechanisms of RCD, ubiquitination and deubiquitination enable post-translational regulation of signaling by modulating substrate degradation and signal transduction. Deubiquitinases (DUBs) are involved in diverse molecular pathways of RCD. Some DUBs modulate multiple modalities of RCD by regulating various substrates and are powerful regulators of cell fate. However, the therapeutic targeting of DUB is limited, as the physiological consequences of modulating DUBs cannot be predicted. In this review, the mechanisms of DUBs that regulate multiple types of RCD are summarized. This comprehensive summary aims to improve our understanding of the complex DUB/RCD regulatory axis comprising various molecular mechanisms for diverse physiological processes. Additionally, this review will enable the understanding of the advantages of therapeutic targeting of DUBs and developing strategies to overcome the side effects associated with the therapeutic applications of DUB modulators.
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Affiliation(s)
- Choong-Sil Lee
- Integrated OMICS for Biomedical Science, World Class University, Yonsei University, Seoul 120-749, Korea;
| | - Seungyeon Kim
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Korea; (S.K.); (G.H.)
| | - Gyuho Hwang
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Korea; (S.K.); (G.H.)
| | - Jaewhan Song
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Korea; (S.K.); (G.H.)
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8
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Jia P, Zhang W, Xiang Y, Lu X, Liu W, Jia K, Yi M. Ubiquitin-specific protease 5 was involved in the interferon response to RGNNV in sea perch (Lateolabrax japonicus). FISH & SHELLFISH IMMUNOLOGY 2020; 103:239-247. [PMID: 32437860 DOI: 10.1016/j.fsi.2020.04.065] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Revised: 03/25/2020] [Accepted: 04/29/2020] [Indexed: 06/11/2023]
Abstract
Deubiquitinases are widely involved in the regulation of the virus-triggered type I interferon (IFN) signaling. Here, we found sea perch (Lateolabrax japonicus) ubiquitin-specific protease 5 (LjUSP5) was a negative regulatory factor of the red-spotted grouper nervous necrosis virus (RGNNV)-triggered IFN response. LjUSP5 encoded a polypeptide of 830 amino acids, containing a zinc finger UBP domain (residues 197-270 aa), two ubiquitin-associated domains (residues 593-607 aa; 628-665 aa), and one UBP domain (residues 782-807 aa), and shared the closest genetic relationship with the USP5 of Larimichthys crocea. Quantitative RT-PCR analysis showed that LjUSP5 was ubiquitously expressed and up-regulated significantly in all inspected tissues post RGNNV infection, and its transcripts significantly increased in brain, liver and kidney tissues post RGNNV infection. LjUSP5 was up-regulated in cultured LJB cells after poly I:C and RGNNV treatments. In addition, overexpression of LjUSP5 significantly inhibited the activation of zebrafish IFN 1 promoter and promoted RGNNV replication in vitro. Furthermore, LjUSP5 inhibited the activation of zebrafish IFN 1 promoter induced by key genes of retinoic acid-inducible gene I-like receptors signaling pathway. Our findings provides useful information for further elucidating the mechanism underlying NNV infection.
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Affiliation(s)
- Peng Jia
- School of Marine Sciences, Sun Yat-sen University, Guangzhou, Guangdong, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, Guangdong, China; Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, Guangdong, China.
| | - Wanwan Zhang
- School of Marine Sciences, Sun Yat-sen University, Guangzhou, Guangdong, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, Guangdong, China; Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, Guangdong, China.
| | - Yangxi Xiang
- School of Marine Sciences, Sun Yat-sen University, Guangzhou, Guangdong, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, Guangdong, China; Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, Guangdong, China.
| | - Xiaobing Lu
- School of Marine Sciences, Sun Yat-sen University, Guangzhou, Guangdong, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, Guangdong, China; Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, Guangdong, China.
| | - Wei Liu
- School of Marine Sciences, Sun Yat-sen University, Guangzhou, Guangdong, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, Guangdong, China; Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, Guangdong, China.
| | - Kuntong Jia
- School of Marine Sciences, Sun Yat-sen University, Guangzhou, Guangdong, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, Guangdong, China; Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, Guangdong, China.
| | - Meisheng Yi
- School of Marine Sciences, Sun Yat-sen University, Guangzhou, Guangdong, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, Guangdong, China; Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, Guangdong, China.
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9
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Qian G, Zhu L, Huang C, Liu Y, Ren Y, Ding Y, Qian W, Xu Q, Zheng H, Lv H. Ubiquitin specific protease 5 negatively regulates the IFNs-mediated antiviral activity via targeting SMURF1. Int Immunopharmacol 2020; 87:106763. [PMID: 32683298 DOI: 10.1016/j.intimp.2020.106763] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Revised: 06/03/2020] [Accepted: 06/28/2020] [Indexed: 02/06/2023]
Abstract
Type I interferons are broadly used for antiviral therapy in clinical. However, the IFNs-mediated antiviral efficacy is commonly restricted by negative regulators. Here, we show that the ubiquitin-specific protease 5 (USP5) inhibits the IFNs-induced p-STAT1 activation (phosphorylation at tyrosine site of STAT1) and its downstream antiviral genes expression. We clarify that USP5 physically interacts with SMURF1 (Smad ubiquitination regulating factor 1) and IFNs signaling regulates the interaction and turnover of both proteins. USP5 enhances the stability and turnover of SMURF1 via decreasing its polyubiquitin expression level, which caused STAT1 to decrease. Importantly, USP5 is also involved in the SMURF1-mediated antiviral response, and its small-molecule inhibitor PYR41 remarkably enhances the IFNs antiviral efficacy. These findings reveal a previously unrecognized function of the USP5 and USP5-SMURF1 axis in regulating the IFNs-mediated antiviral activity.
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Affiliation(s)
- Guanghui Qian
- Institute of Pediatric Research, Children's Hospital of Soochow University, Suzhou, Jiangsu Province 215025, China
| | - Liyan Zhu
- Medical College of Soochow University, Suzhou 215123, China
| | - Chengcheng Huang
- Institute of Pediatric Research, Children's Hospital of Soochow University, Suzhou, Jiangsu Province 215025, China
| | - Ying Liu
- Institute of Pediatric Research, Children's Hospital of Soochow University, Suzhou, Jiangsu Province 215025, China
| | - Ying Ren
- Medical College of Soochow University, Suzhou 215123, China
| | - Yueyue Ding
- Institute of Pediatric Research, Children's Hospital of Soochow University, Suzhou, Jiangsu Province 215025, China
| | - Weiguo Qian
- Institute of Pediatric Research, Children's Hospital of Soochow University, Suzhou, Jiangsu Province 215025, China
| | - Qiuqin Xu
- Institute of Pediatric Research, Children's Hospital of Soochow University, Suzhou, Jiangsu Province 215025, China
| | - Hui Zheng
- Medical College of Soochow University, Suzhou 215123, China.
| | - Haitao Lv
- Institute of Pediatric Research, Children's Hospital of Soochow University, Suzhou, Jiangsu Province 215025, China.
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10
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Du Y, Lin J, Zhang R, Yang W, Quan H, Zang L, Han Y, Li B, Sun H, Wu J. Ubiquitin specific peptidase 5 promotes ovarian cancer cell proliferation through deubiquitinating HDAC2. Aging (Albany NY) 2019; 11:9778-9793. [PMID: 31727867 PMCID: PMC6874447 DOI: 10.18632/aging.102425] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Accepted: 10/28/2019] [Indexed: 12/14/2022]
Abstract
Globally, epithelial ovarian cancer (EOC) is the most common gynecological malignancy with poor prognosis. The expression and oncogenic roles of ubiquitin specific peptidase 5 (USP5) have been reported in several cancers except EOC. In the current study, USP5 amplification was highly prevalent in patients with EOC and associated with higher mRNA expression of USP5. USP5 amplification and overexpression was positively correlated with poor prognosis of patients of ovarian serous carcinomas. Disruption of USP5 profoundly repressed cell proliferation by inducing cell cycle G0/G1 phase arrest in ovarian cancer cells. Additionally, USP5 knockdown inhibited xenograft growth in nude mice. Knockdown of USP5 decreased histone deacetylase 2 (HDAC2) expression and increased p27 (an important cell cycle inhibitor) expression in vitro and in vivo. The promoting effects of USP5 overexpression on cell proliferation and cell cycle transition, as well as the inhibitory effects of USP5 overexpression on p27 expression were mediated by HDAC2. Moreover, USP5 interacted with HDAC2, and disruption of USP5 enhanced the ubiquitination of HDAC2. HDAC2 protein was positively correlated USP5 protein, and negatively correlated with p27 protein in ovarian serous carcinomas tissues. Collectively, our data suggest the oncogenic function of USP5 and the potential regulatory mechanisms in ovarian carcinogenesis.
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Affiliation(s)
- Yanhua Du
- Department of Gynecology, Obstetrics and Gynecology Hospital of Fudan University, Shanghai 200011, P. R. China.,Shanghai Key Laboratory of Female Reproductive Endocrine Related Diseases, Shanghai 200011, P. R. China
| | - Jun Lin
- Pathology Center, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080, P. R. China
| | - Rulin Zhang
- Department of Laboratory Medicine, Shanghai General Hospital, Shanghai Jiao Tong University, Shanghai 200080, P. R. China
| | - Wanli Yang
- Department of Biochemistry and Molecular Cell Biology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, P. R. China
| | - Heng Quan
- Department of Laboratory Medicine, Shanghai General Hospital, Shanghai Jiao Tong University, Shanghai 200080, P. R. China
| | - Lijuan Zang
- Pathology Center, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080, P. R. China
| | - Yaqin Han
- Pathology Center, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080, P. R. China
| | - Bing Li
- Department of Biochemistry and Molecular Cell Biology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, P. R. China
| | - Hong Sun
- Department of Gynecology, Obstetrics and Gynecology Hospital of Fudan University, Shanghai 200011, P. R. China
| | - Jun Wu
- Department of Laboratory Medicine, Shanghai General Hospital, Shanghai Jiao Tong University, Shanghai 200080, P. R. China
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11
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USP5 promotes tumorigenesis and progression of pancreatic cancer by stabilizing FoxM1 protein. Biochem Biophys Res Commun 2017; 492:48-54. [PMID: 28807830 DOI: 10.1016/j.bbrc.2017.08.040] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2017] [Accepted: 08/10/2017] [Indexed: 02/08/2023]
Abstract
Increased ubiquitin-specific protease 5 (USP5) has been associated with tumorigenesis of malignancy including glioblastoma, melanoma and hepatocellular carcinoma. However, the role of USP5 in tumorigenesis of pancreatic ductal adenocarcinoma (PDAC) has not been studied yet. In this study, we demonstrated that USP5 was significantly upregulated in a panel of PDAC cell lines and correlated with FoxM1 protein expression. USP5 knockdown inhibited proliferation of PANC-1 and SW1990, two PDAC cell lines. In the mouse xenografted pancreatic tumor model, suppression of USP5 significantly decreased tumor growth, correlated with down regulation of FoxM1. Additionally, we found that overexpression of USP5 stabilized the FoxM1 protein in PDAC cells. Overexpression of USP5 extended the half-life of FoxM1. Knockdown of USP5 in PANC-1 cells decreased FoxM1 protein level while the proteasome inhibitor MG-132 treatment restored FoxM1 expression. We also found that endogenous USP5 was coimmunoprecipitated with an endogenous FoxM1 from PANC-1 cells while FoxM1 was also coimmunoprecipitated with USP5. Furthermore, we also confirmed that USP5 regulated proliferation of PDAC via FoxM1 by rescuing the inhibitory effect of USP5 knockdown with ectopic expression of FoxM1 in USP5-depleted cells. Taken together, our study demonstrates that USP5 plays a critical role in tumorigenesis and progression of pancreatic cancer by stabilizing FoxM1 protein, and provides a rationale for USP5 being a potential therapeutic approach against PDAC.
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12
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Wang CH, Huang YC, Chen PY, Cheng YJ, Kao HH, Pi H, Chien CT. USP5/Leon deubiquitinase confines postsynaptic growth by maintaining ubiquitin homeostasis through Ubiquilin. eLife 2017; 6. [PMID: 28489002 PMCID: PMC5438252 DOI: 10.7554/elife.26886] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Accepted: 05/09/2017] [Indexed: 12/14/2022] Open
Abstract
Synapse formation and growth are tightly controlled processes. How synaptic growth is terminated after reaching proper size remains unclear. Here, we show that Leon, the Drosophila USP5 deubiquitinase, controls postsynaptic growth. In leon mutants, postsynaptic specializations of neuromuscular junctions are dramatically expanded, including the subsynaptic reticulum, the postsynaptic density, and the glutamate receptor cluster. Expansion of these postsynaptic features is caused by a disruption of ubiquitin homeostasis with accumulation of free ubiquitin chains and ubiquitinated substrates in the leon mutant. Accumulation of Ubiquilin (Ubqn), the ubiquitin receptor whose human homolog ubiquilin 2 is associated with familial amyotrophic lateral sclerosis, also contributes to defects in postsynaptic growth and ubiquitin homeostasis. Importantly, accumulations of postsynaptic proteins cause different aspects of postsynaptic overgrowth in leon mutants. Thus, the deubiquitinase Leon maintains ubiquitin homeostasis and proper Ubqn levels, preventing postsynaptic proteins from accumulation to confine postsynaptic growth. DOI:http://dx.doi.org/10.7554/eLife.26886.001
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Affiliation(s)
- Chien-Hsiang Wang
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan.,Institute of Neuroscience, National Yang Ming University, Taipei, Taiwan
| | - Yi-Chun Huang
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan.,Department of Biomedical Sciences, Chang Gung University, Taoyuan, Taiwan
| | - Pei-Yi Chen
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan.,Institute of Neuroscience, National Yang Ming University, Taipei, Taiwan
| | - Ying-Ju Cheng
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Hsiu-Hua Kao
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Haiwei Pi
- Department of Biomedical Sciences, Chang Gung University, Taoyuan, Taiwan
| | - Cheng-Ting Chien
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan.,Institute of Neuroscience, National Yang Ming University, Taipei, Taiwan
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13
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Usp5 functions as an oncogene for stimulating tumorigenesis in hepatocellular carcinoma. Oncotarget 2017; 8:50655-50664. [PMID: 28881591 PMCID: PMC5584183 DOI: 10.18632/oncotarget.16901] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Accepted: 03/28/2017] [Indexed: 12/30/2022] Open
Abstract
As deubiquitinases, several ubiquitin specific protease members have been reported to mediate tumorigenesis. Although ubiquitin specific protease 5 (Usp5) was previously demonstrated to suppress p53 transcriptional activity and DNA repair, its role in carcinogenesis remains elusive. In this study, we sought to define a novel role of Usp5 in tumorigenesis. It was found that Usp5 was significantly upregulated in hepatocellular carcinoma (HCC) cells and most clinical specimens. Further functional investigation also showed that Usp5 knockdown suppressed cell proliferation, migration, drug resistance and induced apoptosis; on the other hand, Usp5 overexpression promoted colony formation, migration, drug resistance and tumorigenesis. Additionally, the inactivated p14ARF-p53 signaling was observed in Usp5 overexpressed HCC cells, while this signaling was activated by Usp5 knockdown. Therefore, our data demonstrated that Usp5 contributed to hepatocarcinogenesis by acting as an oncogene, which provides new insights into the pathogenesis of HCC and explores a promising molecular target for HCC diagnosis and therapy.
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14
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Ling X, Huang Q, Xu Y, Jin Y, Feng Y, Shi W, Ye X, Lin Y, Hou L, Lin X. The deubiquitinating enzyme Usp5 regulates Notch and RTK signaling duringDrosophilaeye development. FEBS Lett 2017; 591:875-888. [PMID: 28140449 DOI: 10.1002/1873-3468.12580] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Revised: 01/24/2017] [Accepted: 01/25/2017] [Indexed: 12/16/2022]
Affiliation(s)
- Xuemei Ling
- School of Optometry and Ophthalmology and Eye Hospital; Wenzhou Medical University; Zhejiang China
| | - Qinzhu Huang
- Taizhou Hospital of Zhejiang Province; Wenzhou Medical University; Linhai Zhejiang China
| | - Yanqin Xu
- School of Optometry and Ophthalmology and Eye Hospital; Wenzhou Medical University; Zhejiang China
| | - Yuxiao Jin
- School of Optometry and Ophthalmology and Eye Hospital; Wenzhou Medical University; Zhejiang China
| | - Ying Feng
- School of Optometry and Ophthalmology and Eye Hospital; Wenzhou Medical University; Zhejiang China
| | - Weijie Shi
- School of Optometry and Ophthalmology and Eye Hospital; Wenzhou Medical University; Zhejiang China
| | - Xiaolei Ye
- School of Optometry and Ophthalmology and Eye Hospital; Wenzhou Medical University; Zhejiang China
| | - Yi Lin
- School of Optometry and Ophthalmology and Eye Hospital; Wenzhou Medical University; Zhejiang China
| | - Ling Hou
- School of Optometry and Ophthalmology and Eye Hospital; Wenzhou Medical University; Zhejiang China
| | - Xinhua Lin
- School of Optometry and Ophthalmology and Eye Hospital; Wenzhou Medical University; Zhejiang China
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15
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Qian G, Ren Y, Zuo Y, Yuan Y, Zhao P, Wang X, Cheng Q, Liu J, Zhang L, Guo T, Liu C, Zheng H. Smurf1 represses TNF-α production through ubiquitination and destabilization of USP5. Biochem Biophys Res Commun 2016; 474:491-496. [DOI: 10.1016/j.bbrc.2016.04.135] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Accepted: 04/26/2016] [Indexed: 02/02/2023]
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16
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Kovács L, Nagy O, Pál M, Udvardy A, Popescu O, Deák P. Role of the deubiquitylating enzyme DmUsp5 in coupling ubiquitin equilibrium to development and apoptosis in Drosophila melanogaster. PLoS One 2015; 10:e0120875. [PMID: 25806519 PMCID: PMC4373725 DOI: 10.1371/journal.pone.0120875] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Accepted: 01/27/2015] [Indexed: 01/07/2023] Open
Abstract
Protein ubiquitylation is a dynamic process that affects the function and stability of proteins and controls essential cellular processes ranging from cell proliferation to cell death. This process is regulated through the balanced action of E3 ubiquitin ligases and deubiquitylating enzymes (DUB) which conjugate ubiquitins to, and remove them from target proteins, respectively. Our genetic analysis has revealed that the deubiquitylating enzyme DmUsp5 is required for maintenance of the ubiquitin equilibrium, cell survival and normal development in Drosophila. Loss of the DmUsp5 function leads to late larval lethality accompanied by the induction of apoptosis. Detailed analyses at a cellular level demonstrated that DmUsp5 mutants carry multiple abnormalities, including a drop in the free monoubiquitin level, the excessive accumulation of free polyubiquitins, polyubiquitylated proteins and subunits of the 26S proteasome. A shortage in free ubiquitins results in the induction of a ubiquitin stress response previously described only in the unicellular budding yeast. It is characterized by the induction of the proteasome-associated deubiquitylase DmUsp14 and sensitivity to cycloheximide. Removal of DmUsp5 also activates the pro-apoptotic machinery thereby resulting in widespread apoptosis, indicative of an anti-apoptotic role of DmUsp5. Collectively, the pleiotropic effects of a loss of DmUsp5 function can be explained in terms of the existence of a limited pool of free monoubiquitins which makes the ubiquitin-dependent processes mutually interdependent.
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Affiliation(s)
- Levente Kovács
- Department of Genetics, University of Szeged, Szeged, Hungary
- Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - Olga Nagy
- Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - Margit Pál
- Department of Genetics, University of Szeged, Szeged, Hungary
- Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - Andor Udvardy
- Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - Octavian Popescu
- Molecular Biology Center, Interdisciplinary Research Institute on Bio-Nano-Sciences, Babes-Bolyai University, Cluj-Napoca, Romania
| | - Péter Deák
- Department of Genetics, University of Szeged, Szeged, Hungary
- Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
- * E-mail:
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17
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Wang CH, Chen GC, Chien CT. The deubiquitinase Leon/USP5 regulates ubiquitin homeostasis during Drosophila development. Biochem Biophys Res Commun 2014; 452:369-75. [PMID: 25152394 DOI: 10.1016/j.bbrc.2014.08.069] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Accepted: 08/14/2014] [Indexed: 01/09/2023]
Abstract
Ubiquitination and the reverse process deubiquitination regulate protein stability and function during animal development. The Drosophila USP5 homolog Leon functions as other family members of unconventional deubiquitinases, disassembling free, substrate-unconjugated polyubiquitin chains to replenish the pool of mono-ubiquitin, and maintaining cellular ubiquitin homeostasis. However, the significance of Leon/USP5 in animal development is still unexplored. In this study, we generated leon mutants to show that Leon is essential for animal viability and tissue integrity during development. Both free and substrate-conjugated polyubiquitin chains accumulate in leon mutants, suggesting that abnormal ubiquitin homeostasis caused tissue disorder and lethality in leon mutants. Further analysis of protein expression profiles in leon mutants shows that the levels of all proteasomal subunits were elevated. Also, proteasomal enzymatic activities were elevated in leon mutants. However, proteasomal degradation of ubiquitinated substrates was impaired. Thus, aberrant ubiquitin homeostasis in leon mutants disrupts normal proteasomal degradation, which is compensated by elevating the levels of proteasomal subunits and activities. Ultimately, the failure to fully compensate the dysfunctional proteasome in leon mutants leads to animal lethality and tissue disorder.
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Affiliation(s)
- Chien-Hsiang Wang
- Institute of Neuroscience, National Yang-Ming University, Taipei 112, Taiwan; Institute of Molecular Biology, Academia Sinica, Taipei 115, Taiwan
| | - Guang-Chao Chen
- Institute of Biological Chemistry, Academia Sinica, Taipei 115, Taiwan
| | - Cheng-Ting Chien
- Institute of Neuroscience, National Yang-Ming University, Taipei 112, Taiwan; Institute of Molecular Biology, Academia Sinica, Taipei 115, Taiwan.
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