1
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Webster SF, Ghalei H. Maturation of small nucleolar RNAs: from production to function. RNA Biol 2023; 20:715-736. [PMID: 37796118 PMCID: PMC10557570 DOI: 10.1080/15476286.2023.2254540] [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] [Accepted: 08/28/2023] [Indexed: 10/06/2023] Open
Abstract
Small Nucleolar RNAs (snoRNAs) are an abundant group of non-coding RNAs with well-defined roles in ribosomal RNA processing, folding and chemical modification. Besides their classic roles in ribosome biogenesis, snoRNAs are also implicated in several other cellular activities including regulation of splicing, transcription, RNA editing, cellular trafficking, and miRNA-like functions. Mature snoRNAs must undergo a series of processing steps tightly regulated by transiently associating factors and coordinated with other cellular processes including transcription and splicing. In addition to their mature forms, snoRNAs can contribute to gene expression regulation through their derivatives and degradation products. Here, we review the current knowledge on mechanisms of snoRNA maturation, including the different pathways of processing, and the regulatory mechanisms that control snoRNA levels and complex assembly. We also discuss the significance of studying snoRNA maturation, highlight the gaps in the current knowledge and suggest directions for future research in this area.
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Affiliation(s)
- Sarah F. Webster
- Biochemistry, Cell, and Developmental Biology Graduate Program, Emory University, Atlanta, Georgia, USA
- Department of Biochemistry, Emory University, Atlanta, Georgia, USA
| | - Homa Ghalei
- Department of Biochemistry, Emory University, Atlanta, Georgia, USA
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2
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Dreggors-Walker RE, Cohen LN, Khoshnevis S, Marchand V, Motorin Y, Ghalei H. Studies of mutations of assembly factor Hit 1 in budding yeast suggest translation defects as the molecular basis for PEHO syndrome. J Biol Chem 2022; 298:102261. [PMID: 35843310 PMCID: PMC9418376 DOI: 10.1016/j.jbc.2022.102261] [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: 05/09/2022] [Revised: 07/07/2022] [Accepted: 07/08/2022] [Indexed: 11/28/2022] Open
Abstract
Regulation of protein synthesis is critical for control of gene expression in all cells. Ribosomes are ribonucleoprotein machines responsible for translating cellular proteins. Defects in ribosome production, function, or regulation are detrimental to the cell and cause human diseases, such as progressive encephalopathy with edema, hypsarrhythmia, and optic atrophy (PEHO) syndrome. PEHO syndrome is a devastating neurodevelopmental disorder caused by mutations in the ZNHIT3 gene, which encodes an evolutionarily conserved nuclear protein. The precise mechanisms by which ZNHIT3 mutations lead to PEHO syndrome are currently unclear. Studies of the human zinc finger HIT-type containing protein 3 homolog in budding yeast (Hit1) revealed that this protein is critical for formation of small nucleolar ribonucleoprotein complexes that are required for rRNA processing and 2′-O-methylation. Here, we use budding yeast as a model system to reveal the basis for the molecular pathogenesis of PEHO syndrome. We show that missense mutations modeling those found in PEHO syndrome patients cause a decrease in steady-state Hit1 protein levels, a significant reduction of box C/D snoRNA levels, and subsequent defects in rRNA processing and altered cellular translation. Using RiboMethSeq analysis of rRNAs isolated from actively translating ribosomes, we reveal site-specific changes in the rRNA modification pattern of PEHO syndrome mutant yeast cells. Our data suggest that PEHO syndrome is a ribosomopathy and reveal potential new aspects of the molecular basis of this disease in translation dysregulation.
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Affiliation(s)
- R Elizabeth Dreggors-Walker
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia 30322, USA; Graduate Program in Biochemistry, Cell and Developmental Biology (BCDB), Emory University, Atlanta, Georgia 30322, USA
| | - Lauren N Cohen
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia 30322, USA
| | - Sohail Khoshnevis
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia 30322, USA
| | - Virginie Marchand
- Université de Lorraine, UAR2008/US40 IBSLor, CNRS-INSERM, Biopôle, 9 Avenue de la Forêt de Haye, 54505 Vandoeuvre-les-Nancy, France
| | - Yuri Motorin
- Université de Lorraine, UMR7365 IMoPA, CNRS- Biopôle, 9 Avenue de la Forêt de Haye, 54505 Vandoeuvre-les-Nancy, France
| | - Homa Ghalei
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia 30322, USA.
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3
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Serna M, González-Corpas A, Cabezudo S, López-Perrote A, Degliesposti G, Zarzuela E, Skehel JM, Muñoz J, Llorca O. CryoEM of RUVBL1-RUVBL2-ZNHIT2, a complex that interacts with pre-mRNA-processing-splicing factor 8. Nucleic Acids Res 2021; 50:1128-1146. [PMID: 34951455 PMCID: PMC8789047 DOI: 10.1093/nar/gkab1267] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 12/03/2021] [Accepted: 12/10/2021] [Indexed: 12/24/2022] Open
Abstract
Biogenesis of the U5 small nuclear ribonucleoprotein (snRNP) is an essential and highly regulated process. In particular, PRPF8, one of U5 snRNP main components, requires HSP90 working in concert with R2TP, a cochaperone complex containing RUVBL1 and RUVBL2 AAA-ATPases, and additional factors that are still poorly characterized. Here, we use biochemistry, interaction mapping, mass spectrometry and cryoEM to study the role of ZNHIT2 in the regulation of the R2TP chaperone during the biogenesis of PRPF8. ZNHIT2 forms a complex with R2TP which depends exclusively on the direct interaction of ZNHIT2 with the RUVBL1–RUVBL2 ATPases. The cryoEM analysis of this complex reveals that ZNHIT2 alters the conformation and nucleotide state of RUVBL1–RUVBL2, affecting its ATPase activity. We characterized the interactions between R2TP, PRPF8, ZNHIT2, ECD and AAR2 proteins. Interestingly, PRPF8 makes a direct interaction with R2TP and this complex can incorporate ZNHIT2 and other proteins involved in the biogenesis of PRPF8 such as ECD and AAR2. Together, these results show that ZNHIT2 participates in the assembly of the U5 snRNP as part of a network of contacts between assembly factors required for PRPF8 biogenesis and the R2TP-HSP90 chaperone, while concomitantly regulating the structure and nucleotide state of R2TP.
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Affiliation(s)
- Marina Serna
- Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, 28029 Madrid, Spain
| | - Ana González-Corpas
- Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, 28029 Madrid, Spain
| | - Sofía Cabezudo
- Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, 28029 Madrid, Spain
| | - Andrés López-Perrote
- Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, 28029 Madrid, Spain
| | - Gianluca Degliesposti
- MRC Laboratory of Molecular Biology. Francis Crick Avenue. Cambridge Biomedical Campus, Cambridge CB2 0QH. UK
| | - Eduardo Zarzuela
- Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, 28029 Madrid, Spain
| | - J Mark Skehel
- MRC Laboratory of Molecular Biology. Francis Crick Avenue. Cambridge Biomedical Campus, Cambridge CB2 0QH. UK
| | - Javier Muñoz
- Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, 28029 Madrid, Spain
| | - Oscar Llorca
- Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, 28029 Madrid, Spain
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4
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The Mammalian Ecdysoneless Protein Interacts with RNA Helicase DDX39A To Regulate Nuclear mRNA Export. Mol Cell Biol 2021; 41:e0010321. [PMID: 33941617 PMCID: PMC8224239 DOI: 10.1128/mcb.00103-21] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The mammalian orthologue of ecdysoneless (ECD) protein is required for embryogenesis, cell cycle progression, and mitigation of endoplasmic reticulum stress. Here, we identified key components of the mRNA export complexes as binding partners of ECD and characterized the functional interaction of ECD with key mRNA export-related DEAD BOX protein helicase DDX39A. We find that ECD is involved in RNA export through its interaction with DDX39A. ECD knockdown (KD) blocks mRNA export from the nucleus to the cytoplasm, which is rescued by expression of full-length ECD but not an ECD mutant that is defective in interaction with DDX39A. We have previously shown that ECD protein is overexpressed in ErbB2+ breast cancers (BC). In this study, we extended the analyses to two publicly available BC mRNA The Cancer Genome Atlas (TCGA) and Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) data sets. In both data sets, ECD mRNA overexpression correlated with short patient survival, specifically ErbB2+ BC. In the METABRIC data set, ECD overexpression also correlated with poor patient survival in triple-negative breast cancer (TNBC). Furthermore, ECD KD in ErbB2+ BC cells led to a decrease in ErbB2 mRNA level due to a block in its nuclear export and was associated with impairment of oncogenic traits. These findings provide novel mechanistic insight into the physiological and pathological functions of ECD.
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5
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Abel Y, Paiva ACF, Bizarro J, Chagot ME, Santo PE, Robert MC, Quinternet M, Vandermoere F, Sousa PMF, Fort P, Charpentier B, Manival X, Bandeiras TM, Bertrand E, Verheggen C. NOPCHAP1 is a PAQosome cofactor that helps loading NOP58 on RUVBL1/2 during box C/D snoRNP biogenesis. Nucleic Acids Res 2021; 49:1094-1113. [PMID: 33367824 PMCID: PMC7826282 DOI: 10.1093/nar/gkaa1226] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Revised: 11/13/2020] [Accepted: 12/11/2020] [Indexed: 12/15/2022] Open
Abstract
The PAQosome is a large complex composed of the HSP90/R2TP chaperone and a prefoldin-like module. It promotes the biogenesis of cellular machineries but it is unclear how it discriminates closely related client proteins. Among the main PAQosome clients are C/D snoRNPs and in particular their core protein NOP58. Using NOP58 mutants and proteomic experiments, we identify different assembly intermediates and show that C12ORF45, which we rename NOPCHAP1, acts as a bridge between NOP58 and PAQosome. NOPCHAP1 makes direct physical interactions with the CC-NOP domain of NOP58 and domain II of RUVBL1/2 AAA+ ATPases. Interestingly, NOPCHAP1 interaction with RUVBL1/2 is disrupted upon ATP binding. Moreover, while it robustly binds both yeast and human NOP58, it makes little interactions with NOP56 and PRPF31, two other closely related CC-NOP proteins. Expression of NOP58, but not NOP56 or PRPF31, is decreased in NOPCHAP1 KO cells. We propose that NOPCHAP1 is a client-loading PAQosome cofactor that selects NOP58 to promote box C/D snoRNP assembly.
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Affiliation(s)
- Yoann Abel
- IGMM, CNRS, Univ Montpellier, Montpellier, France.,Equipe labellisée Ligue Nationale Contre le Cancer, Montpellier, France.,IGH, CNRS, Univ Montpellier, Montpellier, France
| | - Ana C F Paiva
- iBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, Oeiras, 2781-901, Portugal.,Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, Oeiras, 2780-157, Portugal
| | - Jonathan Bizarro
- IGMM, CNRS, Univ Montpellier, Montpellier, France.,Equipe labellisée Ligue Nationale Contre le Cancer, Montpellier, France
| | | | - Paulo E Santo
- iBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, Oeiras, 2781-901, Portugal.,Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, Oeiras, 2780-157, Portugal
| | - Marie-Cécile Robert
- IGMM, CNRS, Univ Montpellier, Montpellier, France.,Equipe labellisée Ligue Nationale Contre le Cancer, Montpellier, France.,IGH, CNRS, Univ Montpellier, Montpellier, France
| | - Marc Quinternet
- Université de Lorraine, CNRS, INSERM, IBSLor, Biophysics and Structural Biology Core Facility, F-54000, Nancy, France
| | | | - Pedro M F Sousa
- iBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, Oeiras, 2781-901, Portugal.,Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, Oeiras, 2780-157, Portugal
| | | | | | - Xavier Manival
- Université de Lorraine, CNRS, IMoPA, F-54000 Nancy, France
| | - Tiago M Bandeiras
- iBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, Oeiras, 2781-901, Portugal.,Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, Oeiras, 2780-157, Portugal
| | - Edouard Bertrand
- IGMM, CNRS, Univ Montpellier, Montpellier, France.,Equipe labellisée Ligue Nationale Contre le Cancer, Montpellier, France.,IGH, CNRS, Univ Montpellier, Montpellier, France
| | - Céline Verheggen
- IGMM, CNRS, Univ Montpellier, Montpellier, France.,Equipe labellisée Ligue Nationale Contre le Cancer, Montpellier, France.,IGH, CNRS, Univ Montpellier, Montpellier, France
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6
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Rodríguez CF, Llorca O. RPAP3 C-Terminal Domain: A Conserved Domain for the Assembly of R2TP Co-Chaperone Complexes. Cells 2020; 9:cells9051139. [PMID: 32384603 PMCID: PMC7290369 DOI: 10.3390/cells9051139] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 04/28/2020] [Accepted: 05/02/2020] [Indexed: 11/25/2022] Open
Abstract
The Rvb1-Rvb2-Tah1-Pih1 (R2TP) complex is a co-chaperone complex that works together with HSP90 in the activation and assembly of several macromolecular complexes, including RNA polymerase II (Pol II) and complexes of the phosphatidylinositol-3-kinase-like family of kinases (PIKKs), such as mTORC1 and ATR/ATRIP. R2TP is made of four subunits: RuvB-like protein 1 (RUVBL1) and RuvB-like 2 (RUVBL2) AAA-type ATPases, RNA polymerase II-associated protein 3 (RPAP3), and the Protein interacting with Hsp90 1 (PIH1) domain-containing protein 1 (PIH1D1). R2TP associates with other proteins as part of a complex co-chaperone machinery involved in the assembly and maturation of a growing list of macromolecular complexes. Recent progress in the structural characterization of R2TP has revealed an alpha-helical domain at the C-terminus of RPAP3 that is essential to bring the RUVBL1 and RUVBL2 ATPases to R2TP. The RPAP3 C-terminal domain interacts directly with RUVBL2 and it is also known as RUVBL2-binding domain (RBD). Several human proteins contain a region homologous to the RPAP3 C-terminal domain, and some are capable of assembling R2TP-like complexes, which could have specialized functions. Only the RUVBL1-RUVBL2 ATPase complex and a protein containing an RPAP3 C-terminal-like domain are found in all R2TP and R2TP-like complexes. Therefore, the RPAP3 C-terminal domain is one of few components essential for the formation of all R2TP and R2TP-like co-chaperone complexes.
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Affiliation(s)
| | - Oscar Llorca
- Correspondence: ; Tel.: +34-91-732-8000 (ext. 3000/3033)
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7
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RPAP3 provides a flexible scaffold for coupling HSP90 to the human R2TP co-chaperone complex. Nat Commun 2018; 9:1501. [PMID: 29662061 PMCID: PMC5902453 DOI: 10.1038/s41467-018-03942-1] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Accepted: 03/21/2018] [Indexed: 01/13/2023] Open
Abstract
The R2TP/Prefoldin-like co-chaperone, in concert with HSP90, facilitates assembly and cellular stability of RNA polymerase II, and complexes of PI3-kinase-like kinases such as mTOR. However, the mechanism by which this occurs is poorly understood. Here we use cryo-EM and biochemical studies on the human R2TP core (RUVBL1–RUVBL2–RPAP3–PIH1D1) which reveal the distinctive role of RPAP3, distinguishing metazoan R2TP from the smaller yeast equivalent. RPAP3 spans both faces of a single RUVBL ring, providing an extended scaffold that recruits clients and provides a flexible tether for HSP90. A 3.6 Å cryo-EM structure reveals direct interaction of a C-terminal domain of RPAP3 and the ATPase domain of RUVBL2, necessary for human R2TP assembly but absent from yeast. The mobile TPR domains of RPAP3 map to the opposite face of the ring, associating with PIH1D1, which mediates client protein recruitment. Thus, RPAP3 provides a flexible platform for bringing HSP90 into proximity with diverse client proteins. The R2TP/PFDL co-chaperone facilitates assembly of RNA polymerase II and PI3-kinase-like kinases such as mTOR by a so far unknown mechanism. Here authors provide the cryo-EM structure of human R2TP, which shows how RPAP3 serves as a flexible platform to recruit HSP90 to diverse client proteins.
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8
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Gauthier MS, Cloutier P, Coulombe B. Role of the PAQosome in Regulating Arrangement of Protein Quaternary Structure in Health and Disease. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1106:25-36. [PMID: 30484151 DOI: 10.1007/978-3-030-00737-9_3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The PAQosome, formerly known as the R2TP/PFDL complex, is an eleven-subunit cochaperone complex that assists HSP90 in the assembly of numerous large multisubunit protein complexes involved in essential cellular functions such as protein synthesis, ribosome biogenesis, transcription, splicing, and others. In this review, we discuss possible mechanisms of action and role of phosphorylation in the assembly of client complexes by the PAQosome as well as its potential role in cancer, ciliogenesis and ciliopathies.
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Affiliation(s)
| | | | - Benoit Coulombe
- Institut de Recherches Cliniques de Montréal, QC, Canada. .,Department of Biochemistry and Molecular Medicine, Université de Montréal, QC, Canada.
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9
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Mao YQ, Houry WA. The Role of Pontin and Reptin in Cellular Physiology and Cancer Etiology. Front Mol Biosci 2017; 4:58. [PMID: 28884116 PMCID: PMC5573869 DOI: 10.3389/fmolb.2017.00058] [Citation(s) in RCA: 84] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Accepted: 08/03/2017] [Indexed: 12/29/2022] Open
Abstract
Pontin (RUVBL1, TIP49, TIP49a, Rvb1) and Reptin (RUVBL2, TIP48, TIP49b, Rvb2) are highly conserved ATPases of the AAA+ (ATPases Associated with various cellular Activities) superfamily and are involved in various cellular processes that are important for oncogenesis. First identified as being upregulated in hepatocellular carcinoma and colorectal cancer, their overexpression has since been shown in multiple cancer types such as breast, lung, gastric, esophageal, pancreatic, kidney, bladder as well as lymphatic, and leukemic cancers. However, their exact functions are still quite unknown as they interact with many molecular complexes with vastly different downstream effectors. Within the nucleus, Pontin and Reptin participate in the TIP60 and INO80 complexes important for chromatin remodeling. Although not transcription factors themselves, Pontin and Reptin modulate the transcriptional activities of bona fide proto-oncogenes such as MYC and β-catenin. They associate with proteins involved in DNA damage repair such as PIKK complexes as well as with the core complex of Fanconi anemia pathway. They have also been shown to be important for cell cycle progression, being involved in assembly of telomerase, mitotic spindle, RNA polymerase II, and snoRNPs. When the two ATPases localize to the cytoplasm, they were reported to promote cancer cell invasion and metastasis. Due to their various roles in carcinogenesis, it is not surprising that Pontin and Reptin are proving to be important biomarkers for diagnosis and prognosis of various cancers. They are also current targets for the development of new therapeutic anticancer drugs.
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Affiliation(s)
- Yu-Qian Mao
- Department of Biochemistry, University of TorontoToronto, ON, Canada
| | - Walid A Houry
- Department of Biochemistry, University of TorontoToronto, ON, Canada.,Department of Chemistry, University of TorontoToronto, ON, Canada
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10
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Massenet S, Bertrand E, Verheggen C. Assembly and trafficking of box C/D and H/ACA snoRNPs. RNA Biol 2017; 14:680-692. [PMID: 27715451 PMCID: PMC5519232 DOI: 10.1080/15476286.2016.1243646] [Citation(s) in RCA: 121] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Revised: 09/09/2016] [Accepted: 09/27/2016] [Indexed: 12/23/2022] Open
Abstract
Box C/D and box H/ACA snoRNAs are abundant non-coding RNAs that localize in the nucleolus and mostly function as guides for nucleotide modifications. While a large pool of snoRNAs modifies rRNAs, an increasing number of snoRNAs could also potentially target mRNAs. ScaRNAs belong to a family of specific RNAs that localize in Cajal bodies and that are structurally similar to snoRNAs. Most scaRNAs are involved in snRNA modification, while telomerase RNA, which contains H/ACA motifs, functions in telomeric DNA synthesis. In this review, we describe how box C/D and H/ACA snoRNAs are processed and assembled with core proteins to form functional RNP particles. Their biogenesis involve several transport factors that first direct pre-snoRNPs to Cajal bodies, where some processing steps are believed to take place, and then to nucleoli. Assembly of core proteins involves the HSP90/R2TP chaperone-cochaperone system for both box C/D and H/ACA RNAs, but also several factors specific for each family. These assembly factors chaperone unassembled core proteins, regulate the formation and disassembly of pre-snoRNP intermediates, and control the activity of immature particles. The AAA+ ATPase RUVBL1 and RUVBL2 belong to the R2TP co-chaperones and play essential roles in snoRNP biogenesis, as well as in the formation of other macro-molecular complexes. Despite intensive research, their mechanisms of action are still incompletely understood.
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Affiliation(s)
- Séverine Massenet
- Ingénierie Moléculaire et Physiopathologie Articulaire, UMR 7365 CNRS, 9 Avenue de la forêt de Haye, 54505 Vandoeuvre-les-Nancy Cedex, France, Université de Lorraine, Campus Biologie –Santé, CS 50184, 54505 Vandoeuvre-les-Nancy Cedex, France
| | - Edouard Bertrand
- Institut de Génétique Moléculaire de Montpellier, UMR 5535 CNRS, 1919 route de Mende, 34293 Montpellier cedex 5, France, Université de Montpellier, 163 rue Auguste Broussonnet, 34090 Montpellier, France
| | - Céline Verheggen
- Institut de Génétique Moléculaire de Montpellier, UMR 5535 CNRS, 1919 route de Mende, 34293 Montpellier cedex 5, France, Université de Montpellier, 163 rue Auguste Broussonnet, 34090 Montpellier, France
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11
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Malinová A, Cvačková Z, Matějů D, Hořejší Z, Abéza C, Vandermoere F, Bertrand E, Staněk D, Verheggen C. Assembly of the U5 snRNP component PRPF8 is controlled by the HSP90/R2TP chaperones. J Cell Biol 2017; 216:1579-1596. [PMID: 28515276 PMCID: PMC5461031 DOI: 10.1083/jcb.201701165] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Revised: 03/22/2017] [Accepted: 04/04/2017] [Indexed: 12/23/2022] Open
Abstract
The pre-mRNA splicing factor PRPF8 is a crucial component of the U5 snRNP. Using quantitative proteomics, Malinová et al. show that assembly of the U5 snRNP is controlled by the HSP90/R2TP chaperones and that Retinitis pigmentosa–associated mutations in PRPF8 impair PRPF8 quality control and U5 snRNP chaperone-mediated assembly. Splicing is catalyzed by the spliceosome, a complex of five major small nuclear ribonucleoprotein particles (snRNPs). The pre-mRNA splicing factor PRPF8 is a crucial component of the U5 snRNP, and together with EFTUD2 and SNRNP200, it forms a central module of the spliceosome. Using quantitative proteomics, we identified assembly intermediates containing PRPF8, EFTUD2, and SNRNP200 in association with the HSP90/R2TP complex, its ZNHIT2 cofactor, and additional proteins. HSP90 and R2TP bind unassembled U5 proteins in the cytoplasm, stabilize them, and promote the formation of the U5 snRNP. We further found that PRPF8 mutants causing Retinitis pigmentosa assemble less efficiently with the U5 snRNP and bind more strongly to R2TP, with one mutant retained in the cytoplasm in an R2TP-dependent manner. We propose that the HSP90/R2TP chaperone system promotes the assembly of a key module of U5 snRNP while assuring the quality control of PRPF8. The proteomics data further reveal new interactions between R2TP and the tuberous sclerosis complex (TSC), pointing to a potential link between growth signals and the assembly of key cellular machines.
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Affiliation(s)
- Anna Malinová
- Institute of Molecular Genetics, Czech Academy of Sciences, 142 20 Prague, Czech Republic.,Faculty of Science, Charles University in Prague, 128 00 Prague, Czech Republic
| | - Zuzana Cvačková
- Institute of Molecular Genetics, Czech Academy of Sciences, 142 20 Prague, Czech Republic
| | - Daniel Matějů
- Institute of Molecular Genetics, Czech Academy of Sciences, 142 20 Prague, Czech Republic
| | - Zuzana Hořejší
- Institute of Molecular Genetics, Czech Academy of Sciences, 142 20 Prague, Czech Republic
| | - Claire Abéza
- Institut de Génétique Moléculaire de Montpellier, Centre National de la Recherche Scientifique, University of Montpellier, 34293 Montpellier, France
| | - Franck Vandermoere
- Institut de Génomique Fonctionnelle, Centre National de la Recherche Scientifique, University of Montpellier, 34090 Montpellier, France
| | - Edouard Bertrand
- Institut de Génétique Moléculaire de Montpellier, Centre National de la Recherche Scientifique, University of Montpellier, 34293 Montpellier, France
| | - David Staněk
- Institute of Molecular Genetics, Czech Academy of Sciences, 142 20 Prague, Czech Republic
| | - Céline Verheggen
- Institut de Génétique Moléculaire de Montpellier, Centre National de la Recherche Scientifique, University of Montpellier, 34293 Montpellier, France
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12
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Bragantini B, Tiotiu D, Rothé B, Saliou JM, Marty H, Cianférani S, Charpentier B, Quinternet M, Manival X. Functional and Structural Insights of the Zinc-Finger HIT protein family members Involved in Box C/D snoRNP Biogenesis. J Mol Biol 2016; 428:2488-2506. [DOI: 10.1016/j.jmb.2016.04.028] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2015] [Revised: 04/20/2016] [Accepted: 04/23/2016] [Indexed: 11/29/2022]
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