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Nakauma-González JA, Rijnders M, Noordsij MTW, Martens JWM, van der Veldt AAM, Lolkema MPJ, Boormans JL, van de Werken HJG. Whole-genome mapping of APOBEC mutagenesis in metastatic urothelial carcinoma identifies driver hotspot mutations and a novel mutational signature. CELL GENOMICS 2024; 4:100528. [PMID: 38552621 PMCID: PMC11019362 DOI: 10.1016/j.xgen.2024.100528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Revised: 12/22/2023] [Accepted: 03/06/2024] [Indexed: 04/13/2024]
Abstract
Apolipoprotein B mRNA-editing enzyme catalytic polypeptide-like (APOBEC) enzymes mutate specific DNA sequences and hairpin-loop structures, challenging the distinction between passenger and driver hotspot mutations. Here, we characterized 115 whole genomes of metastatic urothelial carcinoma (mUC) to identify APOBEC mutagenic hotspot drivers. APOBEC-associated mutations were detected in 92% of mUCs and were equally distributed across the genome, while APOBEC hotspot mutations (ApoHMs) were enriched in open chromatin. Hairpin loops were frequent targets of didymi (twins in Greek), two hotspot mutations characterized by the APOBEC SBS2 signature, in conjunction with an uncharacterized mutational context (Ap[C>T]). Next, we developed a statistical framework that identified ApoHMs as drivers in coding and non-coding genomic regions of mUCs. Our results and statistical framework were validated in independent cohorts of 23 non-metastatic UCs and 3,744 samples of 17 metastatic cancers, identifying cancer-type-specific drivers. Our study highlights the role of APOBEC in cancer development and may contribute to developing novel targeted therapy options for APOBEC-driven cancers.
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Affiliation(s)
- J Alberto Nakauma-González
- Cancer Computational Biology Center, Erasmus MC Cancer Institute, University Medical Center Rotterdam, 3015 GD Rotterdam, the Netherlands; Department of Urology, Erasmus MC Cancer Institute, University Medical Center Rotterdam, 3015 GD Rotterdam, the Netherlands; Department of Medical Oncology, Erasmus MC Cancer Institute, University Medical Center Rotterdam, 3015 GD Rotterdam, the Netherlands.
| | - Maud Rijnders
- Department of Medical Oncology, Erasmus MC Cancer Institute, University Medical Center Rotterdam, 3015 GD Rotterdam, the Netherlands
| | - Minouk T W Noordsij
- Cancer Computational Biology Center, Erasmus MC Cancer Institute, University Medical Center Rotterdam, 3015 GD Rotterdam, the Netherlands
| | - John W M Martens
- Department of Medical Oncology, Erasmus MC Cancer Institute, University Medical Center Rotterdam, 3015 GD Rotterdam, the Netherlands
| | - Astrid A M van der Veldt
- Department of Medical Oncology, Erasmus MC Cancer Institute, University Medical Center Rotterdam, 3015 GD Rotterdam, the Netherlands; Department of Radiology & Nuclear Medicine, Erasmus MC, University Medical Center Rotterdam, 3015 GD Rotterdam, the Netherlands
| | - Martijn P J Lolkema
- Department of Medical Oncology, Erasmus MC Cancer Institute, University Medical Center Rotterdam, 3015 GD Rotterdam, the Netherlands
| | - Joost L Boormans
- Department of Urology, Erasmus MC Cancer Institute, University Medical Center Rotterdam, 3015 GD Rotterdam, the Netherlands
| | - Harmen J G van de Werken
- Cancer Computational Biology Center, Erasmus MC Cancer Institute, University Medical Center Rotterdam, 3015 GD Rotterdam, the Netherlands; Department of Urology, Erasmus MC Cancer Institute, University Medical Center Rotterdam, 3015 GD Rotterdam, the Netherlands; Department of Immunology, Erasmus MC Cancer Institute, University Medical Center Rotterdam, 3015 GD Rotterdam, the Netherlands.
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Gao F, Zhou H, Huang X, Xie H, Zhou L, Chen J, Zheng S. WDR74 serves as a novel therapeutic target by its oncogenic role in hepatocellular carcinoma. Pathol Res Pract 2023; 248:154622. [PMID: 37331183 DOI: 10.1016/j.prp.2023.154622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2023] [Revised: 05/15/2023] [Accepted: 06/13/2023] [Indexed: 06/20/2023]
Abstract
BACKGROUND Hepatocellular carcinoma (HCC) is one of the most refractory human malignancies. WD repeat-containing protein 74 (WDR74) is involved in the tumorigenesis of various cancers, however, its clinical implications and biological function in HCC have yet to be clearly determined. METHODS Bioinformatics analysis was conducted using various databases, including The Cancer Genome Atlas (TCGA), Gene Expression Omnibus (GEO) and UALCAN. The expression of WDR74 was confirmed in HCC tumor samples and the corresponding adjacent nontumor samples by qRT-PCR, western blot and immunohistochemistry. Functional enrichment analysis was used for the biological function prediction. In vitro experiments were performed to determine the effects of WDR74 on HCC cell proliferation. RESULTS Our findings revealed that WDR74 was markedly upregulated in HCC tissues. Increased WDR74 expression had an unfavorable overall survival (OS). Multivariate Cox regression analysis demonstrated that WDR74 was an independent prognostic factor for OS in patients with HCC. Functional enrichment analysis suggested a significant correlation with cytokine-cytokine receptor interaction pathway in both TCGA-LIHC and GSE112790 datasets. Gene set enrichment analysis showed that WDR74 is probably involved in several pathways, such as MYC targets, ribosome, translation, and cell cycle. Finally, WDR74 knockdown reduced HCC cell proliferation by restraining the G1/S cell cycle transition and inducing apoptosis. CONCLUSIONS The current study demonstrates that elevated WDR74 expression is linked to an accelerated rate of tumor cell proliferation and is indicative of a poorer outcome in patients with HCC. Therefore, WDR74 could be used as a reliable prognostic biomarker and is a potential therapeutic target for HCC.
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Affiliation(s)
- Feng Gao
- Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, China; NHC Key Laboratory of Combined Multi-organ Transplantation, China; Key Laboratory of the diagnosis and treatment of organ Transplantation, Research Unit of Collaborative Diagnosis and Treatment for Hepatobiliary and Pancreatic Cancer, Chinese Academy of Medical Sciences (2019RU019), China; Key Laboratory of Organ Transplantation, Research Center for Diagnosis and Treatment of Hepatobiliary Diseases, Zhejiang Province, Hangzhou 310003, China
| | - Hui Zhou
- College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Xiaosong Huang
- Department of Pharmacy, The Fourth Affiliated Hospital, Zhejiang University School of Medicine, Yiwu 322000, China
| | - Haiyang Xie
- NHC Key Laboratory of Combined Multi-organ Transplantation, China; Key Laboratory of the diagnosis and treatment of organ Transplantation, Research Unit of Collaborative Diagnosis and Treatment for Hepatobiliary and Pancreatic Cancer, Chinese Academy of Medical Sciences (2019RU019), China; Key Laboratory of Organ Transplantation, Research Center for Diagnosis and Treatment of Hepatobiliary Diseases, Zhejiang Province, Hangzhou 310003, China
| | - Lin Zhou
- NHC Key Laboratory of Combined Multi-organ Transplantation, China; Key Laboratory of the diagnosis and treatment of organ Transplantation, Research Unit of Collaborative Diagnosis and Treatment for Hepatobiliary and Pancreatic Cancer, Chinese Academy of Medical Sciences (2019RU019), China; Key Laboratory of Organ Transplantation, Research Center for Diagnosis and Treatment of Hepatobiliary Diseases, Zhejiang Province, Hangzhou 310003, China
| | - Junru Chen
- Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, China; NHC Key Laboratory of Combined Multi-organ Transplantation, China.
| | - Shusen Zheng
- Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, China; NHC Key Laboratory of Combined Multi-organ Transplantation, China; Key Laboratory of the diagnosis and treatment of organ Transplantation, Research Unit of Collaborative Diagnosis and Treatment for Hepatobiliary and Pancreatic Cancer, Chinese Academy of Medical Sciences (2019RU019), China; Key Laboratory of Organ Transplantation, Research Center for Diagnosis and Treatment of Hepatobiliary Diseases, Zhejiang Province, Hangzhou 310003, China.
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3
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Dörner K, Ruggeri C, Zemp I, Kutay U. Ribosome biogenesis factors-from names to functions. EMBO J 2023; 42:e112699. [PMID: 36762427 PMCID: PMC10068337 DOI: 10.15252/embj.2022112699] [Citation(s) in RCA: 37] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 12/13/2022] [Accepted: 01/19/2023] [Indexed: 02/11/2023] Open
Abstract
The assembly of ribosomal subunits is a highly orchestrated process that involves a huge cohort of accessory factors. Most eukaryotic ribosome biogenesis factors were first identified by genetic screens and proteomic approaches of pre-ribosomal particles in Saccharomyces cerevisiae. Later, research on human ribosome synthesis not only demonstrated that the requirement for many of these factors is conserved in evolution, but also revealed the involvement of additional players, reflecting a more complex assembly pathway in mammalian cells. Yet, it remained a challenge for the field to assign a function to many of the identified factors and to reveal their molecular mode of action. Over the past decade, structural, biochemical, and cellular studies have largely filled this gap in knowledge and led to a detailed understanding of the molecular role that many of the players have during the stepwise process of ribosome maturation. Such detailed knowledge of the function of ribosome biogenesis factors will be key to further understand and better treat diseases linked to disturbed ribosome assembly, including ribosomopathies, as well as different types of cancer.
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Affiliation(s)
- Kerstin Dörner
- Department of Biology, Institute of Biochemistry, ETH Zurich, Zurich, Switzerland.,Molecular Life Sciences Ph.D. Program, Zurich, Switzerland
| | - Chiara Ruggeri
- Department of Biology, Institute of Biochemistry, ETH Zurich, Zurich, Switzerland.,RNA Biology Ph.D. Program, Zurich, Switzerland
| | - Ivo Zemp
- Department of Biology, Institute of Biochemistry, ETH Zurich, Zurich, Switzerland
| | - Ulrike Kutay
- Department of Biology, Institute of Biochemistry, ETH Zurich, Zurich, Switzerland
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4
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Kocaman S, Lo YH, Krahn JM, Sobhany M, Dandey VP, Petrovich ML, Etigunta SK, Williams JG, Deterding LJ, Borgnia MJ, Stanley RE. Communication network within the essential AAA-ATPase Rix7 drives ribosome assembly. PNAS NEXUS 2022; 1:pgac118. [PMID: 36090660 PMCID: PMC9437592 DOI: 10.1093/pnasnexus/pgac118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 07/08/2022] [Indexed: 02/06/2023]
Abstract
Rix7 is an essential AAA+ ATPase that functions during the early stages of ribosome biogenesis. Rix7 is composed of three domains including an N-terminal domain (NTD) and two AAA+ domains (D1 and D2) that assemble into an asymmetric stacked hexamer. It was recently established that Rix7 is a presumed protein translocase that removes substrates from preribosomes by translocating them through its central pore. However, how the different domains of Rix7 coordinate their activities within the overall hexameric structure was unknown. We captured cryo-electron microscopy (EM) structures of single and double Walker B variants of full length Rix7. The disordered NTD was not visible in the cryo-EM reconstructions, but cross-linking mass spectrometry revealed that the NTD can associate with the central channel in vitro. Deletion of the disordered NTD enabled us to obtain a structure of the Rix7 hexamer to 2.9 Å resolution, providing high resolution details of critical motifs involved in substrate translocation and interdomain communication. This structure coupled with cell-based assays established that the linker connecting the D1 and D2 domains as well as the pore loops lining the central channel are essential for formation of the large ribosomal subunit. Together, our work shows that Rix7 utilizes a complex communication network to drive ribosome biogenesis.
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Affiliation(s)
- Seda Kocaman
- Department of Health and Human Services, Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, 111 T. W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Yu-Hua Lo
- Department of Health and Human Services, Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, 111 T. W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Juno M Krahn
- Department of Health and Human Services, Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, 111 T. W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Mack Sobhany
- Department of Health and Human Services, Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, 111 T. W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Venkata P Dandey
- Department of Health and Human Services, Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, 111 T. W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Matthew L Petrovich
- Department of Health and Human Services, Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, 111 T. W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Suhas K Etigunta
- Department of Health and Human Services, Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, 111 T. W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Jason G Williams
- Department of Health and Human Services, Epigenetics and Stem Cell Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, 111 T. W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Leesa J Deterding
- Department of Health and Human Services, Epigenetics and Stem Cell Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, 111 T. W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Mario J Borgnia
- Department of Health and Human Services, Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, 111 T. W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Robin E Stanley
- Department of Health and Human Services, Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, 111 T. W. Alexander Drive, Research Triangle Park, NC 27709, USA
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5
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Wu X, Song P, Wang S, Qian Z, Ying J, Gao S, Li W. A Pan-Cancer Analysis of the Oncogenic Role of WD Repeat Domain 74 in Multiple Tumors. Front Genet 2022; 13:860940. [PMID: 35559034 PMCID: PMC9086290 DOI: 10.3389/fgene.2022.860940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Accepted: 03/21/2022] [Indexed: 11/17/2022] Open
Abstract
Although emerging patient-derived samples and cellular-based evidence support the relationship between WDR74 (WD Repeat Domain 74) and carcinogenesis in multiple cancers, no systematic pan-cancer analysis is available. Our preliminary research demonstrated that WDR74 is over-expressed in lung squamous cell carcinoma (LUSC) and related with worse survival. We thus investigated the potential oncogenic roles of WDR74 across 33 tumors based on the database of TCGA (The Cancer Genome Atlas) and GEO (Gene Expression Omnibus). WDR74 is highly expressed in most cancers and correlated with poor prognosis in several cancers (all p < 0.05). Mutation analysis demonstrated that WDR74 is frequently mutated in promoter regions of lung cancer. Moreover, we found that CD8+ T-cells and the fibroblast infiltration level increased in WDR74 over-expressed cancer cells. The GO (Gene Ontology) enrichment analysis of the WDR74 pathway revealed its participation in cellular biogenesis of the RNA metabolism and its critical role in cancer initiation and progression through the tumor cell energy metabolism. Our first pan-cancer study inferred a relatively comprehensive understanding of the oncogenic roles of WDR74 across various cancers.
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Affiliation(s)
- Xiaoxuan Wu
- Department of Pathology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Peng Song
- Department of Thoracic Surgical Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Shun Wang
- Beidou Academic and Research Center, Beidou Life Science, Guangzhou, China
| | - Zhirong Qian
- Beidou Academic and Research Center, Beidou Life Science, Guangzhou, China.,Guangdong Provincial Key Laboratory of Digestive Cancer Research, Scientific Research Center, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, China.,Department of Radiation Oncology, Fujian Medical University Union Hospital, Fuzhou, China
| | - Jianming Ying
- Department of Pathology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Shugeng Gao
- Department of Thoracic Surgical Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Wenbin Li
- Department of Pathology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
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6
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Cai Z, Mei Y, Jiang X, Shi X. WDR74 promotes proliferation and metastasis in colorectal cancer cells through regulating the Wnt/β-catenin signaling pathway. Open Life Sci 2021; 16:920-929. [PMID: 34553072 PMCID: PMC8422980 DOI: 10.1515/biol-2021-0096] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 07/22/2021] [Accepted: 07/23/2021] [Indexed: 12/13/2022] Open
Abstract
Colon cancer (CRC) is a common type of cancer and has a high incidence worldwide. Protein 74 (WDR74), which consists of the WD repetition sequence, has been previously associated with tumor tumorigenesis. However, its mechanism of action in CRC remains unclear. Here, we found that WDR74 expression was upregulated in CRC tissues and cells. Downregulation of WDR74 repressed the proliferation and cell cycles in CRC cells. In addition, WDR74 knockdown induced cell apoptosis and suppressed both cell metastasis and invasion. Mechanistically, WDR74 decreased the phosphorylation of β-catenin and induced nuclear β-catenin accumulation, activating the Wnt/β-catenin signaling pathway in CRC cells. Further investigation showed that blocking the Wnt/β-catenin signaling pathway by XAV-939 reversed the effects of WDR74 on cell proliferation, migration, and invasion in HCT116 cells. Overall, WDR74 induced β-catenin translocation to the nucleus and activated the Wnt/β-Catenin, thus facilitated CRC cell proliferation and metastasis. In summary, WDR74 could be a potential target for the intervention of CRC.
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Affiliation(s)
- Zhou Cai
- Department of Medical, Wuhan City College, Wuhan City, Hubei Province, 430083, China
| | - Yan Mei
- Department of Medical, Wuhan City College, Wuhan City, Hubei Province, 430083, China
| | - Xiaoye Jiang
- Department of Medical, Wuhan City College, Wuhan City, Hubei Province, 430083, China
| | - Xingfeng Shi
- Department of Colorectal Surgery, The Ninth People's Hospital of Chongqing, No. 69, Jialing Village, Beibei District, Chongqing City, 400700, China
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7
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Frazier MN, Pillon MC, Kocaman S, Gordon J, Stanley RE. Structural overview of macromolecular machines involved in ribosome biogenesis. Curr Opin Struct Biol 2021; 67:51-60. [PMID: 33099228 PMCID: PMC8058114 DOI: 10.1016/j.sbi.2020.09.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 09/04/2020] [Accepted: 09/08/2020] [Indexed: 12/17/2022]
Abstract
The production of ribosomes is essential for ensuring the translational capacity of cells. Because of its high energy demand ribosome production is subject to stringent cellular controls. Hundreds of ribosome assembly factors are required to facilitate assembly of nascent ribosome particles with high fidelity. Many ribosome assembly factors organize into macromolecular machines that drive complex steps of the production pathway. Recent advances in structural biology, in particular cryo-EM, have provided detailed information about the structure and function of these higher order enzymatic assemblies. Here, we summarize recent structures revealing molecular insight into these macromolecular machines with an emphasis on the interplay between discrete active sites.
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Affiliation(s)
- Meredith N Frazier
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, 111 T. W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Monica C Pillon
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, 111 T. W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Seda Kocaman
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, 111 T. W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Jacob Gordon
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, 111 T. W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Robin E Stanley
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, 111 T. W. Alexander Drive, Research Triangle Park, NC 27709, USA.
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8
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Li Y, Chen F, Shen W, Li B, Xiang R, Qu L, Zhang C, Li G, Xie H, Katanaev VL, Jia L. WDR74 induces nuclear β-catenin accumulation and activates Wnt-responsive genes to promote lung cancer growth and metastasis. Cancer Lett 2020; 471:103-115. [PMID: 31838084 DOI: 10.1016/j.canlet.2019.12.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Revised: 11/25/2019] [Accepted: 12/09/2019] [Indexed: 12/24/2022]
Abstract
Lung cancer has been notorious for its lack of advance in clinical therapy, urging for effective therapeutic targets. WD repeat-containing protein 74 (WDR74) has previously been implicated in tumorigenesis, but its mechanistic functions remain not well understood. Herein, WDR74 expression was observed to be increased upon lung cancer progression from healthy normal tissues to the primary cancer and further to the metastatic cancer. Through gain- and loss-of-function approaches, we found that WDR74 regulated lung cancer cell proliferation, cell cycle progression, chemoresistance and cell aggressiveness in vitro. Moreover, a xenograft mouse model disclosed that WDR74 knockout inhibited lung cancer growth and metastasis, whereas WDR74 overexpression reciprocally enhanced these characteristics. Mechanistically, WDR74 promoted nuclear β-catenin accumulation and drove downstream Wnt-responsive genes, thus revealing that WDR74 activated the Wnt/β-catenin signaling pathway. Collectively, WDR74 inducing nuclear β-catenin accumulation and driving the downstream Wnt-responsive genes expression facilitates lung cancer growth and metastasis. WDR74 can serve as a candidate target for the prevention and treatment of lung cancer in clinic.
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Affiliation(s)
- Yumei Li
- Cancer Metastasis Alert and Prevention Center, College of Chemistry; Fujian Provincial Key Laboratory of Cancer Metastasis Chemoprevention and Chemotherapy, Fuzhou University; Institute of Oceanography, Minjiang University, Fuzhou, Fujian, 350108, China
| | - Fan Chen
- Cancer Metastasis Alert and Prevention Center, College of Chemistry; Fujian Provincial Key Laboratory of Cancer Metastasis Chemoprevention and Chemotherapy, Fuzhou University; Institute of Oceanography, Minjiang University, Fuzhou, Fujian, 350108, China
| | - Weiyu Shen
- Cancer Metastasis Alert and Prevention Center, College of Chemistry; Fujian Provincial Key Laboratory of Cancer Metastasis Chemoprevention and Chemotherapy, Fuzhou University; Institute of Oceanography, Minjiang University, Fuzhou, Fujian, 350108, China
| | - Bifei Li
- Cancer Metastasis Alert and Prevention Center, College of Chemistry; Fujian Provincial Key Laboratory of Cancer Metastasis Chemoprevention and Chemotherapy, Fuzhou University; Institute of Oceanography, Minjiang University, Fuzhou, Fujian, 350108, China
| | - Rong Xiang
- Department of Pathology, Fuzhou General Hospital of Nanjing Military Command, Fuzhou, 350025, China
| | - Lijuan Qu
- Department of Pathology, Fuzhou General Hospital of Nanjing Military Command, Fuzhou, 350025, China
| | - Chen Zhang
- Cancer Metastasis Alert and Prevention Center, College of Chemistry; Fujian Provincial Key Laboratory of Cancer Metastasis Chemoprevention and Chemotherapy, Fuzhou University; Institute of Oceanography, Minjiang University, Fuzhou, Fujian, 350108, China
| | - Gao Li
- Cancer Metastasis Alert and Prevention Center, College of Chemistry; Fujian Provincial Key Laboratory of Cancer Metastasis Chemoprevention and Chemotherapy, Fuzhou University; Institute of Oceanography, Minjiang University, Fuzhou, Fujian, 350108, China
| | - Huanzhang Xie
- Cancer Metastasis Alert and Prevention Center, College of Chemistry; Fujian Provincial Key Laboratory of Cancer Metastasis Chemoprevention and Chemotherapy, Fuzhou University; Institute of Oceanography, Minjiang University, Fuzhou, Fujian, 350108, China
| | - Vladimir L Katanaev
- Cancer Metastasis Alert and Prevention Center, College of Chemistry; Fujian Provincial Key Laboratory of Cancer Metastasis Chemoprevention and Chemotherapy, Fuzhou University; Institute of Oceanography, Minjiang University, Fuzhou, Fujian, 350108, China; School of Biomedicine, Far Eastern Federal University, Vladivostok, Russia; Translational Research Center in Oncohaematology, Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Switzerland.
| | - Lee Jia
- Cancer Metastasis Alert and Prevention Center, College of Chemistry; Fujian Provincial Key Laboratory of Cancer Metastasis Chemoprevention and Chemotherapy, Fuzhou University; Institute of Oceanography, Minjiang University, Fuzhou, Fujian, 350108, China.
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9
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WDR74 modulates melanoma tumorigenesis and metastasis through the RPL5-MDM2-p53 pathway. Oncogene 2020; 39:2741-2755. [PMID: 32005977 DOI: 10.1038/s41388-020-1179-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2019] [Revised: 01/06/2020] [Accepted: 01/21/2020] [Indexed: 11/08/2022]
Abstract
The key molecules and underlying mechanisms of melanoma metastasis remain poorly understood. Using isobaric tag for relative and absolute quantitation (iTRAQ) proteomic screening, probing of patients' samples, functional verification, and mechanistic validation, we identified the important role of the WD repeat-containing protein 74 (WDR74) in melanoma progression and metastasis. Through gain- and loss-of-function approaches, WDR74 was found to promote cell proliferation, apoptosis resistance, and aggressive behavior in vitro. Moreover, WDR74 contributed to melanoma growth and metastasis in vivo. Mechanistically, WDR74 modulates RPL5 protein levels and consequently regulates MDM2 and insulates the ubiquitination degradation of p53 by MDM2. Our study is the first to reveal the oncogenic role of WDR74 in melanoma progression and the regulatory effect of WDR74 on the RPL5-MDM2-p53 pathway. Collectively, WDR74 can serve as a candidate target for the prevention and treatment of melanoma in the clinic.
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10
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Shaping the Nascent Ribosome: AAA-ATPases in Eukaryotic Ribosome Biogenesis. Biomolecules 2019; 9:biom9110715. [PMID: 31703473 PMCID: PMC6920918 DOI: 10.3390/biom9110715] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 11/04/2019] [Accepted: 11/05/2019] [Indexed: 02/08/2023] Open
Abstract
AAA-ATPases are molecular engines evolutionarily optimized for the remodeling of proteins and macromolecular assemblies. Three AAA-ATPases are currently known to be involved in the remodeling of the eukaryotic ribosome, a megadalton range ribonucleoprotein complex responsible for the translation of mRNAs into proteins. The correct assembly of the ribosome is performed by a plethora of additional and transiently acting pre-ribosome maturation factors that act in a timely and spatially orchestrated manner. Minimal disorder of the assembly cascade prohibits the formation of functional ribosomes and results in defects in proliferation and growth. Rix7, Rea1, and Drg1, which are well conserved across eukaryotes, are involved in different maturation steps of pre-60S ribosomal particles. These AAA-ATPases provide energy for the efficient removal of specific assembly factors from pre-60S particles after they have fulfilled their function in the maturation cascade. Recent structural and functional insights have provided the first glimpse into the molecular mechanism of target recognition and remodeling by Rix7, Rea1, and Drg1. Here we summarize current knowledge on the AAA-ATPases involved in eukaryotic ribosome biogenesis. We highlight the latest insights into their mechanism of mechano-chemical complex remodeling driven by advanced cryo-EM structures and the use of highly specific AAA inhibitors.
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11
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Cryo-EM structure of the essential ribosome assembly AAA-ATPase Rix7. Nat Commun 2019; 10:513. [PMID: 30705282 PMCID: PMC6355894 DOI: 10.1038/s41467-019-08373-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 12/28/2018] [Indexed: 01/24/2023] Open
Abstract
Rix7 is an essential type II AAA-ATPase required for the formation of the large ribosomal subunit. Rix7 has been proposed to utilize the power of ATP hydrolysis to drive the removal of assembly factors from pre-60S particles, but the mechanism of release is unknown. Rix7's mammalian homolog, NVL2 has been linked to cancer and mental illness disorders, highlighting the need to understand the molecular mechanisms of this essential machine. Here we report the cryo-EM reconstruction of the tandem AAA domains of Rix7 which form an asymmetric stacked homohexameric ring. We trapped Rix7 with a polypeptide in the central channel, revealing Rix7's role as a molecular unfoldase. The structure establishes that type II AAA-ATPases lacking the aromatic-hydrophobic motif within the first AAA domain can engage a substrate throughout the entire central channel. The structure also reveals that Rix7 contains unique post-α7 insertions within both AAA domains important for Rix7 function.
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12
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Liu J, Zhao M, Yuan B, Gu S, Zheng M, Zou J, Jin J, Liu T, Feng XH. WDR74 functions as a novel coactivator in TGF-β signaling. J Genet Genomics 2018; 45:639-650. [PMID: 30594465 DOI: 10.1016/j.jgg.2018.08.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Revised: 08/09/2018] [Accepted: 08/27/2018] [Indexed: 12/25/2022]
Abstract
Smads are critical intracellular signal transducers for transforming growth factor-β (TGF-β) in mammalian cells. In this study, we have identified WD repeat-containing protein 74 (WDR74) as a novel transcriptional coactivator for Smads in the canonical TGF-β signaling pathway. Through direct interactions with Smad proteins, WDR74 enhances TGF-β-mediated phosphorylation and nuclear accumulation of Smad2 and Smad3. Consequently, WDR74 enables stronger transcriptional responses and more robust TGF-β-induced physiological responses. Our findings have elucidated a critical role of WDR74 in regulating TGF-β signaling.
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Affiliation(s)
- Jinquan Liu
- MOE Key Laboratory of Biosystems Homeostasis & Protection and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, Hangzhou 310058, China; Department of Biochemistry and Molecular Biology, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Meiling Zhao
- MOE Key Laboratory of Biosystems Homeostasis & Protection and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, Hangzhou 310058, China
| | - Bo Yuan
- MOE Key Laboratory of Biosystems Homeostasis & Protection and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, Hangzhou 310058, China
| | - Shuchen Gu
- MOE Key Laboratory of Biosystems Homeostasis & Protection and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, Hangzhou 310058, China
| | - Mingjie Zheng
- MOE Key Laboratory of Biosystems Homeostasis & Protection and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, Hangzhou 310058, China; Institute of Translational Medicine, School of Medicine, Zhejiang University, Hangzhou 310058, China
| | - Jian Zou
- Institute of Translational Medicine, School of Medicine, Zhejiang University, Hangzhou 310058, China
| | - Jianping Jin
- Department of Biochemistry and Molecular Biology, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Ting Liu
- MOE Key Laboratory of Biosystems Homeostasis & Protection and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, Hangzhou 310058, China; Department of Cell Biology, School of Medicine, Zhejiang University, Hangzhou 310058, China.
| | - Xin-Hua Feng
- MOE Key Laboratory of Biosystems Homeostasis & Protection and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, Hangzhou 310058, China; Department of Molecular & Cellular Biology and Michael DeBakey Department of Surgery, Baylor College of Medicine, Houston, TX 77030, USA.
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13
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Zhou D, Zhu X, Zheng S, Tan D, Dong MQ, Ye K. Cryo-EM structure of an early precursor of large ribosomal subunit reveals a half-assembled intermediate. Protein Cell 2018; 10:120-130. [PMID: 29557065 PMCID: PMC6340896 DOI: 10.1007/s13238-018-0526-7] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Accepted: 03/04/2018] [Indexed: 11/25/2022] Open
Abstract
Assembly of eukaryotic ribosome is a complicated and dynamic process that involves a series of intermediates. It is unknown how the highly intertwined structure of 60S large ribosomal subunits is established. Here, we report the structure of an early nucleolar pre-60S ribosome determined by cryo-electron microscopy at 3.7 Å resolution, revealing a half-assembled subunit. Domains I, II and VI of 25S/5.8S rRNA pack tightly into a native-like substructure, but domains III, IV and V are not assembled. The structure contains 12 assembly factors and 19 ribosomal proteins, many of which are required for early processing of large subunit rRNA. The Brx1-Ebp2 complex would interfere with the assembly of domains IV and V. Rpf1, Mak16, Nsa1 and Rrp1 form a cluster that consolidates the joining of domains I and II. Our structure reveals a key intermediate on the path to establishing the global architecture of 60S subunits.
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Affiliation(s)
- Dejian Zhou
- Graduate School of Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, 100730, China.,Key Laboratory of RNA Biology, Institute of Biophysics, CAS Center for Excellence in Biomacromolecules, Chinese Academy of Sciences, Beijing, 100101, China.,National Institute of Biological Sciences, Beijing, 102206, China
| | - Xing Zhu
- Key Laboratory of RNA Biology, Institute of Biophysics, CAS Center for Excellence in Biomacromolecules, Chinese Academy of Sciences, Beijing, 100101, China
| | - Sanduo Zheng
- National Institute of Biological Sciences, Beijing, 102206, China
| | - Dan Tan
- National Institute of Biological Sciences, Beijing, 102206, China
| | - Meng-Qiu Dong
- National Institute of Biological Sciences, Beijing, 102206, China
| | - Keqiong Ye
- Graduate School of Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, 100730, China. .,Key Laboratory of RNA Biology, Institute of Biophysics, CAS Center for Excellence in Biomacromolecules, Chinese Academy of Sciences, Beijing, 100101, China. .,University of Chinese Academy of Sciences, Beijing, 100049, China.
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14
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Sanghai ZA, Miller L, Molloy KR, Barandun J, Hunziker M, Chaker-Margot M, Wang J, Chait BT, Klinge S. Modular assembly of the nucleolar pre-60S ribosomal subunit. Nature 2018; 556:126-129. [PMID: 29512650 DOI: 10.1038/nature26156] [Citation(s) in RCA: 108] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 02/23/2018] [Indexed: 12/13/2022]
Abstract
Early co-transcriptional events during eukaryotic ribosome assembly result in the formation of precursors of the small (40S) and large (60S) ribosomal subunits. A multitude of transient assembly factors regulate and chaperone the systematic folding of pre-ribosomal RNA subdomains. However, owing to a lack of structural information, the role of these factors during early nucleolar 60S assembly is not fully understood. Here we report cryo-electron microscopy (cryo-EM) reconstructions of the nucleolar pre-60S ribosomal subunit in different conformational states at resolutions of up to 3.4 Å. These reconstructions reveal how steric hindrance and molecular mimicry are used to prevent both premature folding states and binding of later factors. This is accomplished by the concerted activity of 21 ribosome assembly factors that stabilize and remodel pre-ribosomal RNA and ribosomal proteins. Among these factors, three Brix-domain proteins and their binding partners form a ring-like structure at ribosomal RNA (rRNA) domain boundaries to support the architecture of the maturing particle. The existence of mutually exclusive conformations of these pre-60S particles suggests that the formation of the polypeptide exit tunnel is achieved through different folding pathways during subsequent stages of ribosome assembly. These structures rationalize previous genetic and biochemical data and highlight the mechanisms that drive eukaryotic ribosome assembly in a unidirectional manner.
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Affiliation(s)
- Zahra Assur Sanghai
- Laboratory of Protein and Nucleic Acid Chemistry, The Rockefeller University, New York, New York 10065, USA
| | - Linamarie Miller
- Laboratory of Protein and Nucleic Acid Chemistry, The Rockefeller University, New York, New York 10065, USA.,Tri-Institutional Training Program in Chemical Biology, The Rockefeller University, New York, New York 10065, USA
| | - Kelly R Molloy
- Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, New York, New York 10065, USA
| | - Jonas Barandun
- Laboratory of Protein and Nucleic Acid Chemistry, The Rockefeller University, New York, New York 10065, USA
| | - Mirjam Hunziker
- Laboratory of Protein and Nucleic Acid Chemistry, The Rockefeller University, New York, New York 10065, USA
| | - Malik Chaker-Margot
- Laboratory of Protein and Nucleic Acid Chemistry, The Rockefeller University, New York, New York 10065, USA.,Tri-Institutional Training Program in Chemical Biology, The Rockefeller University, New York, New York 10065, USA
| | - Junjie Wang
- Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, New York, New York 10065, USA
| | - Brian T Chait
- Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, New York, New York 10065, USA
| | - Sebastian Klinge
- Laboratory of Protein and Nucleic Acid Chemistry, The Rockefeller University, New York, New York 10065, USA
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15
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Lo YH, Pillon MC, Stanley RE. Combining X-Ray Crystallography with Small Angle X-Ray Scattering to Model Unstructured Regions of Nsa1 from S. Cerevisiae. J Vis Exp 2018. [PMID: 29364241 DOI: 10.3791/56953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Determination of the full-length structure of ribosome assembly factor Nsa1 from Saccharomyces cerevisiae (S. cerevisiae) is challenging because of the disordered and protease labile C-terminus of the protein. This manuscript describes the methods to purify recombinant Nsa1 from S. cerevisiae for structural analysis by both X-ray crystallography and SAXS. X-ray crystallography was utilized to solve the structure of the well-ordered N-terminal WD40 domain of Nsa1, and then SAXS was used to resolve the structure of the C-terminus of Nsa1 in solution. Solution scattering data was collected from full-length Nsa1 in solution. The theoretical scattering amplitudes were calculated from the high-resolution crystal structure of the WD40 domain, and then a combination of rigid body and ab initio modeling revealed the C-terminus of Nsa1. Through this hybrid approach the quaternary structure of the entire protein was reconstructed. The methods presented here should be generally applicable for the hybrid structural determination of other proteins composed of a mix of structured and unstructured domains.
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Affiliation(s)
- Yu-Hua Lo
- Signal Transduction Laboratory, National Institutes of Environmental Health Sciences, Department of Health and Human Services, National Institutes of Health
| | - Monica C Pillon
- Signal Transduction Laboratory, National Institutes of Environmental Health Sciences, Department of Health and Human Services, National Institutes of Health
| | - Robin E Stanley
- Signal Transduction Laboratory, National Institutes of Environmental Health Sciences, Department of Health and Human Services, National Institutes of Health;
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Kater L, Thoms M, Barrio-Garcia C, Cheng J, Ismail S, Ahmed YL, Bange G, Kressler D, Berninghausen O, Sinning I, Hurt E, Beckmann R. Visualizing the Assembly Pathway of Nucleolar Pre-60S Ribosomes. Cell 2017; 171:1599-1610.e14. [PMID: 29245012 PMCID: PMC5745149 DOI: 10.1016/j.cell.2017.11.039] [Citation(s) in RCA: 136] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Revised: 10/13/2017] [Accepted: 11/20/2017] [Indexed: 12/12/2022]
Abstract
Eukaryotic 60S ribosomal subunits are comprised of three rRNAs and ∼50 ribosomal proteins. The initial steps of their formation take place in the nucleolus, but, owing to a lack of structural information, this process is poorly understood. Using cryo-EM, we solved structures of early 60S biogenesis intermediates at 3.3 Å to 4.5 Å resolution, thereby providing insights into their sequential folding and assembly pathway. Besides revealing distinct immature rRNA conformations, we map 25 assembly factors in six different assembly states. Notably, the Nsa1-Rrp1-Rpf1-Mak16 module stabilizes the solvent side of the 60S subunit, and the Erb1-Ytm1-Nop7 complex organizes and connects through Erb1's meandering N-terminal extension, eight assembly factors, three ribosomal proteins, and three 25S rRNA domains. Our structural snapshots reveal the order of integration and compaction of the six major 60S domains within early nucleolar 60S particles developing stepwise from the solvent side around the exit tunnel to the central protuberance.
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Affiliation(s)
- Lukas Kater
- Gene Center Munich and Center of Integrated Protein Science-Munich (CiPS-M), Department of Biochemistry, Feodor-Lynen-Str. 25, University of Munich, 81377 Munich, Germany
| | - Matthias Thoms
- Biochemie-Zentrum der Universität Heidelberg, 69120 Heidelberg, Germany
| | - Clara Barrio-Garcia
- Gene Center Munich and Center of Integrated Protein Science-Munich (CiPS-M), Department of Biochemistry, Feodor-Lynen-Str. 25, University of Munich, 81377 Munich, Germany
| | - Jingdong Cheng
- Gene Center Munich and Center of Integrated Protein Science-Munich (CiPS-M), Department of Biochemistry, Feodor-Lynen-Str. 25, University of Munich, 81377 Munich, Germany
| | - Sherif Ismail
- Biochemie-Zentrum der Universität Heidelberg, 69120 Heidelberg, Germany
| | | | - Gert Bange
- Biochemie-Zentrum der Universität Heidelberg, 69120 Heidelberg, Germany
| | - Dieter Kressler
- Biochemie-Zentrum der Universität Heidelberg, 69120 Heidelberg, Germany
| | - Otto Berninghausen
- Gene Center Munich and Center of Integrated Protein Science-Munich (CiPS-M), Department of Biochemistry, Feodor-Lynen-Str. 25, University of Munich, 81377 Munich, Germany
| | - Irmgard Sinning
- Biochemie-Zentrum der Universität Heidelberg, 69120 Heidelberg, Germany
| | - Ed Hurt
- Biochemie-Zentrum der Universität Heidelberg, 69120 Heidelberg, Germany
| | - Roland Beckmann
- Gene Center Munich and Center of Integrated Protein Science-Munich (CiPS-M), Department of Biochemistry, Feodor-Lynen-Str. 25, University of Munich, 81377 Munich, Germany.
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17
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Hiraishi N, Ishida YI, Sudo H, Nagahama M. WDR74 participates in an early cleavage of the pre-rRNA processing pathway in cooperation with the nucleolar AAA-ATPase NVL2. Biochem Biophys Res Commun 2017; 495:116-123. [PMID: 29107693 DOI: 10.1016/j.bbrc.2017.10.148] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Accepted: 10/27/2017] [Indexed: 10/18/2022]
Abstract
WD repeat-containing protein 74 (WDR74), a nucleolar-localized protein, is the mammalian ortholog of Nsa1, a 60S ribosome assembly factor in yeast. We previously showed that WDR74 associates with MTR4, the nuclear exosome-assisting RNA helicase, whose dissociation is prohibited by an ATPase-deficient mutant of the AAA-type chaperone NVL2. However, the functions and regulation of WDR74 during ribosome biogenesis in cooperation with NVL2 remains unknown. Here, we demonstrated that knockdown of WDR74 leads to significant defects in the pre-rRNA cleavage within the internal transcribed spacer 1 (ITS1), occurring in an early stage of the processing pathway. Interestingly, when the dissociation of WDR74 from the MTR4-containing exonuclease complex was impaired upon expression of the mutant NVL2, the same processing defect, with partial migration of WDR74 from the nucleolus towards the nucleoplasm, was observed. In the nucleoplasm, an increased interaction between WDR74 and MTR4 was detected by in situ proximity ligation assay. Therefore, the dissociation of WDR74 from MTR4 in a late stage of rRNA synthesis is thought to be required for appropriate maturation of the pre-60S particles. These results suggest that the spatiotemporal regulation of ribosome biogenesis in the nucleolus is mediated by the ATPase activity of NVL2.
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Affiliation(s)
- Nobuhiro Hiraishi
- Laboratory of Molecular and Cellular Biochemistry, Meiji Pharmaceutical University, Kiyose, Tokyo 204-8588, Japan
| | - Yo-Ichi Ishida
- Laboratory of Molecular and Cellular Biochemistry, Meiji Pharmaceutical University, Kiyose, Tokyo 204-8588, Japan
| | - Haruka Sudo
- Laboratory of Molecular and Cellular Biochemistry, Meiji Pharmaceutical University, Kiyose, Tokyo 204-8588, Japan
| | - Masami Nagahama
- Laboratory of Molecular and Cellular Biochemistry, Meiji Pharmaceutical University, Kiyose, Tokyo 204-8588, Japan.
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