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Luthuli SD, Shonhai A. The multi-faceted roles of R2TP complex span across regulation of gene expression, translation, and protein functional assembly. Biophys Rev 2023; 15:1951-1965. [PMID: 38192347 PMCID: PMC10771493 DOI: 10.1007/s12551-023-01127-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Accepted: 08/27/2023] [Indexed: 01/10/2024] Open
Abstract
Macromolecular complexes play essential roles in various cellular processes. The assembly of macromolecular assemblies within the cell must overcome barriers imposed by a crowded cellular environment which is characterized by an estimated concentration of biological macromolecules amounting to 100-450 g/L that take up approximately 5-40% of the cytoplasmic volume. The formation of the macromolecular assemblies is facilitated by molecular chaperones in cooperation with their co-chaperones. The R2TP protein complex has emerged as a co-chaperone of Hsp90 that plays an important role in macromolecular assembly. The R2TP complex is composed of a heterodimer of RPAP3:P1H1DI that is in turn complexed to members of the ATPase associated with diverse cellular activities (AAA +), RUVBL1 and RUVBL2 (R1 and R2) families. What makes the R2TP co-chaperone complex particularly important is that it is involved in a wide variety of cellular processes including gene expression, translation, co-translational complex assembly, and posttranslational protein complex formation. The functional versatility of the R2TP co-chaperone complex makes it central to cellular development; hence, it is implicated in various human diseases. In addition, their roles in the development of infectious disease agents has become of interest. In the current review, we discuss the roles of these proteins as co-chaperones regulating Hsp90 and its partnership with Hsp70. Furthermore, we highlight the structure-function features of the individual proteins within the R2TP complex and describe their roles in various cellular processes.
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Affiliation(s)
- Sifiso Duncan Luthuli
- Department of Biochemistry and Microbiology, University of Venda, Thohoyandou, South Africa
| | - Addmore Shonhai
- Department of Biochemistry and Microbiology, University of Venda, Thohoyandou, South Africa
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2
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Antonio LM, Martins GH, Aragão AZB, Quel NG, Zazeri G, Houry WA, Ramos CHI. Unveiling the Role of Sorghum RPAP3 in the Function of R2TP Complex: Insights into Protein Assembly in Plants. PLANTS (BASEL, SWITZERLAND) 2023; 12:2925. [PMID: 37631136 PMCID: PMC10458388 DOI: 10.3390/plants12162925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 08/04/2023] [Accepted: 08/10/2023] [Indexed: 08/27/2023]
Abstract
The chaperone R2TP has multiple subunits that assist in the proper folding, assembly, and stabilization of various protein complexes in cells and its study can offer valuable insights into the regulation and maintenance of protein assemblies in plant systems. The 'T' component of R2TP is Tah1 in yeast, consisting of 111 residues, while its counterpart in humans is RPAP3, with 665 residues. RPAP3 acts as a co-chaperone of Hsp90 and facilitates interactions between RUVBL proteins and other complex components, enhancing the recruitment of client proteins by the R2TP complex. These facts further underscore the relevance of studying this complex in different organisms. The putative gene corresponding to the RPAP3 in Sorghum bicolor, a monocotyledon plant, was cloned, and the protein (396 residues) purified for biochemical characterization. SbRPAP3 exists as a folded monomer and has a RPAP3 domain, which is present in human RPAP3 but absent in yeast Tah1. SbRPAP3 retains its functional capabilities, including binding with RUVBLs, Hsp90, and Hsp70. By elucidating the role of RPAP3 in plant R2TP complex, we can further comprehend the molecular mechanisms underlying plant-specific protein assembly and contribute to advancements in plant biology and biotechnological applications.
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Affiliation(s)
- Larissa Machado Antonio
- Institute of Chemistry, University of Campinas—UNICAMP, Campinas 13100-104, SP, Brazil; (L.M.A.); (G.H.M.); (A.Z.B.A.); (N.G.Q.); (G.Z.)
| | - Gustavo Henrique Martins
- Institute of Chemistry, University of Campinas—UNICAMP, Campinas 13100-104, SP, Brazil; (L.M.A.); (G.H.M.); (A.Z.B.A.); (N.G.Q.); (G.Z.)
| | - Annelize Zambon Barbosa Aragão
- Institute of Chemistry, University of Campinas—UNICAMP, Campinas 13100-104, SP, Brazil; (L.M.A.); (G.H.M.); (A.Z.B.A.); (N.G.Q.); (G.Z.)
| | - Natália Galdi Quel
- Institute of Chemistry, University of Campinas—UNICAMP, Campinas 13100-104, SP, Brazil; (L.M.A.); (G.H.M.); (A.Z.B.A.); (N.G.Q.); (G.Z.)
| | - Gabriel Zazeri
- Institute of Chemistry, University of Campinas—UNICAMP, Campinas 13100-104, SP, Brazil; (L.M.A.); (G.H.M.); (A.Z.B.A.); (N.G.Q.); (G.Z.)
| | - Walid A. Houry
- Department of Biochemistry, University of Toronto, Toronto, ON M5G 1M1, Canada;
- Department of Chemistry, University of Toronto, Toronto, ON M5S 3H6, Canada
| | - Carlos Henrique Inacio Ramos
- Institute of Chemistry, University of Campinas—UNICAMP, Campinas 13100-104, SP, Brazil; (L.M.A.); (G.H.M.); (A.Z.B.A.); (N.G.Q.); (G.Z.)
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3
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The Role of Hsp90-R2TP in Macromolecular Complex Assembly and Stabilization. Biomolecules 2022; 12:biom12081045. [PMID: 36008939 PMCID: PMC9406135 DOI: 10.3390/biom12081045] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 07/19/2022] [Accepted: 07/25/2022] [Indexed: 01/27/2023] Open
Abstract
Hsp90 is a ubiquitous molecular chaperone involved in many cell signaling pathways, and its interactions with specific chaperones and cochaperones determines which client proteins to fold. Hsp90 has been shown to be involved in the promotion and maintenance of proper protein complex assembly either alone or in association with other chaperones such as the R2TP chaperone complex. Hsp90-R2TP acts through several mechanisms, such as by controlling the transcription of protein complex subunits, stabilizing protein subcomplexes before their incorporation into the entire complex, and by recruiting adaptors that facilitate complex assembly. Despite its many roles in protein complex assembly, detailed mechanisms of how Hsp90-R2TP assembles protein complexes have yet to be determined, with most findings restricted to proteomic analyses and in vitro interactions. This review will discuss our current understanding of the function of Hsp90-R2TP in the assembly, stabilization, and activity of the following seven classes of protein complexes: L7Ae snoRNPs, spliceosome snRNPs, RNA polymerases, PIKKs, MRN, TSC, and axonemal dynein arms.
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4
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Dos Santos Morais R, Santo PE, Ley M, Schelcher C, Abel Y, Plassart L, Deslignière E, Chagot ME, Quinternet M, Paiva ACF, Hessmann S, Morellet N, M F Sousa P, Vandermoere F, Bertrand E, Charpentier B, Bandeiras TM, Plisson-Chastang C, Verheggen C, Cianférani S, Manival X. Deciphering cellular and molecular determinants of human DPCD protein in complex with RUVBL1/RUVBL2 AAA-ATPases. J Mol Biol 2022; 434:167760. [PMID: 35901867 DOI: 10.1016/j.jmb.2022.167760] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 06/24/2022] [Accepted: 07/21/2022] [Indexed: 10/16/2022]
Abstract
DPCD is a protein that may play a role in cilia formation and whose absence leads to primary ciliary dyskinesia (PCD), a rare disease caused by impairment of ciliated cells. Except for high-throughput studies that identified DPCD as a possible RUVBL1 (R1) and RUVBL2 (R2) partner, no in-depth cellular, biochemical, and structural investigation involving DPCD have been reported so far. R1 and R2 proteins are ubiquitous highly conserved AAA+ family ATPases that assemble and mature a plethora of macromolecular complexes and are pivotal in numerous cellular processes, especially by guaranteeing a co-chaperoning function within R2TP or R2TP-like machineries. In the present study, we identified DPCD as a new R1R2 partner in vivo. We show that DPCD interacts directly with R1 and R2 in vitro and in cells. We characterized the physico-chemical properties of DPCD in solution and built a 3D model of DPCD. In addition, we used a variety of orthogonal biophysical techniques including small-angle X-ray scattering, structural mass spectrometry and electron microscopy to assess the molecular determinants of DPCD interaction with R1R2. Interestingly, DPCD disrupts the dodecameric state of R1R2 complex upon binding and this interaction occurs mainly via the DII domains of R1R2.
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Affiliation(s)
| | - Paulo E Santo
- iBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2781-901 Oeiras, Portugal; Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras, Portugal
| | - Marie Ley
- Laboratoire de Spectrométrie de Masse BioOrganique, Université de Strasbourg, CNRS, IPHC UMR 7178, Strasbourg 67000, France; Infrastructure Nationale de Protéomique ProFI - FR2048 CNRS, 67087 Strasbourg, France
| | | | - Yoann Abel
- IGH, CNRS, Univ Montpellier, Montpellier, France; Equipe labélisée Ligue Nationale Contre le Cancer, 34293 Montpellier, France
| | - Laura Plassart
- MCD, Centre de Biologie Intégrative (CBI), University of Toulouse, CNRS, UPS, 31062 Toulouse, France
| | - Evolène Deslignière
- Laboratoire de Spectrométrie de Masse BioOrganique, Université de Strasbourg, CNRS, IPHC UMR 7178, Strasbourg 67000, France; Infrastructure Nationale de Protéomique ProFI - FR2048 CNRS, 67087 Strasbourg, France
| | | | - Marc Quinternet
- Université de Lorraine, CNRS, INSERM, IBSLor, Biophysics and Structural Biology Core Facility, F-54000, France
| | - Ana C F Paiva
- iBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2781-901 Oeiras, Portugal; Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras, Portugal
| | - Steve Hessmann
- Laboratoire de Spectrométrie de Masse BioOrganique, Université de Strasbourg, CNRS, IPHC UMR 7178, Strasbourg 67000, France; Infrastructure Nationale de Protéomique ProFI - FR2048 CNRS, 67087 Strasbourg, France
| | - Nelly Morellet
- Très Grandes Infrastructures de Recherche, Institut de Chimie des Substances Naturelles - CNRS, 1 avenue de la Terrasse, 91190 Gif-sur-Yvette, France
| | - Pedro M F Sousa
- iBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2781-901 Oeiras, Portugal; Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras, Portugal
| | | | - Edouard Bertrand
- IGH, CNRS, Univ Montpellier, Montpellier, France; Equipe labélisée Ligue Nationale Contre le Cancer, 34293 Montpellier, France
| | | | - Tiago M Bandeiras
- iBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2781-901 Oeiras, Portugal; Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras, Portugal
| | - Célia Plisson-Chastang
- MCD, Centre de Biologie Intégrative (CBI), University of Toulouse, CNRS, UPS, 31062 Toulouse, France
| | - Céline Verheggen
- IGH, CNRS, Univ Montpellier, Montpellier, France; Equipe labélisée Ligue Nationale Contre le Cancer, 34293 Montpellier, France
| | - Sarah Cianférani
- Laboratoire de Spectrométrie de Masse BioOrganique, Université de Strasbourg, CNRS, IPHC UMR 7178, Strasbourg 67000, France; Infrastructure Nationale de Protéomique ProFI - FR2048 CNRS, 67087 Strasbourg, France
| | - Xavier Manival
- IMoPA, CNRS, Université de Lorraine, Nancy F-54000, France
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Smith AJ, Bustamante-Marin XM, Yin W, Sears PR, Herring LE, Dicheva NN, López-Giráldez F, Mane S, Tarran R, Leigh MW, Knowles MR, Zariwala MA, Ostrowski LE. The role of SPAG1 in the assembly of axonemal dyneins in human airway epithelia. J Cell Sci 2022; 135:jcs259512. [PMID: 35178554 PMCID: PMC8995097 DOI: 10.1242/jcs.259512] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 02/14/2022] [Indexed: 11/20/2022] Open
Abstract
Mutations in SPAG1, a dynein axonemal assembly factor (DNAAF) that facilitates the assembly of dynein arms in the cytoplasm before their transport into the cilium, result in primary ciliary dyskinesia (PCD), a genetically heterogenous disorder characterized by chronic oto-sino-pulmonary disease, infertility and laterality defects. To further elucidate the role of SPAG1 in dynein assembly, we examined its expression, interactions and ciliary defects in control and PCD human airway epithelia. Immunoprecipitations showed that SPAG1 interacts with multiple DNAAFs, dynein chains and canonical components of the R2TP complex. Protein levels of dynein heavy chains (DHCs) and interactions between DHCs and dynein intermediate chains (DICs) were reduced in SPAG1 mutants. We also identified a previously uncharacterized 60 kDa SPAG1 isoform, through examination of PCD subjects with an atypical ultrastructural defect for SPAG1 variants, that can partially compensate for the absence of full-length SPAG1 to assemble a reduced number of outer dynein arms. In summary, our data show that SPAG1 is necessary for axonemal dynein arm assembly by scaffolding R2TP-like complexes composed of several DNAAFs that facilitate the folding and/or binding of the DHCs to the DIC complex.
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Affiliation(s)
- Amanda J. Smith
- Marsico Lung Institute/Cystic Fibrosis Research and Treatment Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Ximena M. Bustamante-Marin
- Marsico Lung Institute/Cystic Fibrosis Research and Treatment Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Weining Yin
- Marsico Lung Institute/Cystic Fibrosis Research and Treatment Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Patrick R. Sears
- Marsico Lung Institute/Cystic Fibrosis Research and Treatment Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Laura E. Herring
- University of North Carolina Proteomics Core Facility, Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Nedyalka N. Dicheva
- University of North Carolina Proteomics Core Facility, Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | | | - Shrikant Mane
- Yale Center for Genome Analysis, Yale University, New Haven, CT 06520, USA
| | - Robert Tarran
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Margaret W. Leigh
- Marsico Lung Institute/Cystic Fibrosis Research and Treatment Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Department of Pediatrics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Michael R. Knowles
- Marsico Lung Institute/Cystic Fibrosis Research and Treatment Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Maimoona A. Zariwala
- Marsico Lung Institute/Cystic Fibrosis Research and Treatment Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Department of Pathology and Laboratory Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Lawrence E. Ostrowski
- Marsico Lung Institute/Cystic Fibrosis Research and Treatment Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
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6
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Puri A, Singh P, Kumar N, Kumar R, Sharma D. Tah1, A Key Component of R2TP Complex that Regulates Assembly of snoRNP, is Involved in De Novo Generation and Maintenance of Yeast Prion [URE3]. J Mol Biol 2021; 433:166976. [PMID: 33811921 DOI: 10.1016/j.jmb.2021.166976] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Revised: 03/02/2021] [Accepted: 03/25/2021] [Indexed: 10/21/2022]
Abstract
The cellular chaperone machinery plays key role in the de novo formation and propagation of yeast prions (infectious protein). Though the role of Hsp70s in the prion maintenance is well studied, how Hsp90 chaperone machinery affects yeast prions remains unclear. In the current study, we examined the role of Hsp90 and its co-chaperones on yeast prions [PSI+] and [URE3]. We show that the overproduction of Hsp90 co-chaperone Tah1, cures [URE3] which is a prion form of native protein Ure2 in yeast. The Hsp90 co-chaperone Tah1 is involved in the assembly of small nucleolar ribonucleoproteins (snoRNP) and chromatin remodelling complexes. We found that Tah1 deletion improves the frequency of de novo appearance of [URE3]. The Tah1 was found to interact with Hsp70. The lack of Tah1 not only represses antagonizing effect of Ssa1 Hsp70 on [URE3] but also improves the prion strength suggesting role of Tah1 in both fibril growth and replication. We show that the N-terminal tetratricopeptide repeat domain of Tah1 is indispensable for [URE3] curing. Tah1 interacts with Ure2, improves its solubility in [URE3] strains, and affects the kinetics of Ure2 fibrillation in vitro. Its inhibitory role on Ure2 fibrillation is proposed to influence [URE3] propagation. The present study shows a novel role of Tah1 in yeast prion propagation, and that Hsp90 not only promotes its role in ribosomal RNA processing but also in the prion maintenance. SUMMARY: Prions are self-perpetuating infectious proteins. What initiates the misfolding of a protein into its prion form is still not clear. The understanding of cellular factors that facilitate or antagonize prions is crucial to gain insight into the mechanism of prion formation and propagation. In the current study, we reveal that Tah1 is a novel modulator of yeast prion [URE3]. The Hsp90 co-chaperone Tah1, is required for the formation of small nucleolar ribonucleoprotein complex. We show that the absence of Tah1 improves the induction of [URE3] prion. The overexpressed Tah1 cures [URE3], and this function is promoted by Hsp90 chaperones. The current study thus provides a novel cellular factor and the underlying mechanism, involved in the prion formation and propagation.
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Affiliation(s)
- Anuradhika Puri
- Council of Scientific and Industrial Research-Institute of Microbial Technology, India
| | - Priyanka Singh
- Council of Scientific and Industrial Research-Institute of Microbial Technology, India
| | - Navinder Kumar
- Council of Scientific and Industrial Research-Institute of Microbial Technology, India
| | - Rajesh Kumar
- School of Basic and Applied Sciences, Central University of Punjab, Bhatinda, India
| | - Deepak Sharma
- Council of Scientific and Industrial Research-Institute of Microbial Technology, India; Academy of Scientific & Innovative Research, India.
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7
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Liu G, Wang L, Pan J. Chlamydomonas WDR92 in association with R2TP-like complex and multiple DNAAFs to regulate ciliary dynein preassembly. J Mol Cell Biol 2020; 11:770-780. [PMID: 30428028 PMCID: PMC6821370 DOI: 10.1093/jmcb/mjy067] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 10/30/2018] [Accepted: 11/13/2018] [Indexed: 11/17/2022] Open
Abstract
The motility of cilia or eukaryotic flagella is powered by the axonemal dyneins, which are preassembled in the cytoplasm by proteins termed dynein arm assembly factors (DNAAFs) before being transported to and assembled on the ciliary axoneme. Here, we characterize the function of WDR92 in Chlamydomonas. Loss of WDR92, a cytoplasmic protein, in a mutant wdr92 generated by DNA insertional mutagenesis resulted in aflagellate cells or cells with stumpy or short flagella, disappearance of axonemal dynein arms, and diminishment of dynein arm heavy chains in the cytoplasm, suggesting that WDR92 is a DNAAF. Immunoprecipitation of WDR92 followed by mass spectrometry identified inner dynein arm heavy chains and multiple DNAAFs including RuvBL1, RPAP3, MOT48, ODA7, and DYX1C. The PIH1 domain-containing protein MOT48 formed a R2TP-like complex with RuvBL1/2 and RPAP3, while PF13, another PIH1 domain-containing protein with function in dynein preassembly, did not. Interestingly, the third PIH1 domain-containing protein TWI1 was not related to flagellar motility. WDR92 physically interacted with the R2TP-like complex and the other identified DNNAFs. Our data suggest that WDR92 functions in association with the HSP90 co-chaperone R2TP-like complex as well as linking other DNAAFs in dynein preassembly.
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Affiliation(s)
- Guang Liu
- MOE Key Laboratory of Protein Sciences, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Limei Wang
- MOE Key Laboratory of Protein Sciences, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Junmin Pan
- MOE Key Laboratory of Protein Sciences, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China.,Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
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8
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Kakihara Y, Kiguchi T, Ohazama A, Saeki M. R2TP/PAQosome as a promising chemotherapeutic target in cancer. JAPANESE DENTAL SCIENCE REVIEW 2020; 56:38-42. [PMID: 31890057 PMCID: PMC6926247 DOI: 10.1016/j.jdsr.2019.08.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 07/27/2019] [Accepted: 08/21/2019] [Indexed: 11/30/2022] Open
Abstract
R2TP/PAQosome (particle for arrangement of quaternary structure) is a novel multisubunit chaperone specialized in the assembly/maturation of protein complexes that are involved in essential cellular processes such as PIKKs (phosphatidylinositol 3-kinase-like kinases) signaling, snoRNP (small nucleolar ribonucleoprotein) biogenesis, and RNAP II (RNA polymerase II) complex formation. In this review article, we describe the current understanding of R2TP/PAQosome functions and characteristics as well as how the chaperone complex is involved in oncogenesis, highlighting DNA damage response, mTOR (mammalian target of rapamycin) pathway as well as snoRNP biogenesis. Also, we discuss its possible involvement in HNSCC (head and neck squamous cell carcinoma) including OSCC (oral squamous cell carcinoma). Finally, we provide an overview of current anti-cancer drug development efforts targeting R2TP/PAQosome.
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Affiliation(s)
- Yoshito Kakihara
- Division of Dental Pharmacology, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Tetsuo Kiguchi
- Division of Dental Pharmacology, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Atsushi Ohazama
- Division of Oral Anatomy, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Makio Saeki
- Division of Dental Pharmacology, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
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9
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Role of the Novel Hsp90 Co-Chaperones in Dynein Arms' Preassembly. Int J Mol Sci 2019; 20:ijms20246174. [PMID: 31817850 PMCID: PMC6940843 DOI: 10.3390/ijms20246174] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Revised: 12/04/2019] [Accepted: 12/04/2019] [Indexed: 12/12/2022] Open
Abstract
The outer and inner dynein arms (ODAs and IDAs) are composed of multiple subunits including dynein heavy chains possessing a motor domain. These complex structures are preassembled in the cytoplasm before being transported to the cilia. The molecular mechanism(s) controlling dynein arms’ preassembly is poorly understood. Recent evidence suggests that canonical R2TP complex, an Hsp-90 co-chaperone, in cooperation with dynein axonemal assembly factors (DNAAFs), plays a crucial role in the preassembly of ODAs and IDAs. Here, we have summarized recent data concerning the identification of novel chaperone complexes and their role in dynein arms’ preassembly and their association with primary cilia dyskinesia (PCD), a human genetic disorder.
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10
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Patel-King RS, Sakato-Antoku M, Yankova M, King SM. WDR92 is required for axonemal dynein heavy chain stability in cytoplasm. Mol Biol Cell 2019; 30:1834-1845. [PMID: 31116681 PMCID: PMC6727741 DOI: 10.1091/mbc.e19-03-0139] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Revised: 04/24/2019] [Accepted: 05/16/2019] [Indexed: 01/01/2023] Open
Abstract
WDR92 associates with a prefoldin-like cochaperone complex and known dynein assembly factors. WDR92 has been very highly conserved and has a phylogenetic signature consistent with it playing a role in motile ciliary assembly or activity. Knockdown of WDR92 expression in planaria resulted in ciliary loss, reduced beat frequency and dyskinetic motion of the remaining ventral cilia. We have now identified a Chlamydomonas wdr92 mutant that encodes a protein missing the last four WD repeats. The wdr92-1 mutant builds only ∼0.7-μm cilia lacking both inner and outer dynein arms, but with intact doublet microtubules and central pair. When cytoplasmic extracts prepared by freeze/thaw from a control strain were fractionated by gel filtration, outer arm dynein components were present in several distinct high molecular weight complexes. In contrast, wdr92-1 extracts almost completely lacked all three outer arm heavy chains, while the IFT dynein heavy chain was present in normal amounts. A wdr92-1 tpg1-2 double mutant builds ∼7-μm immotile flaccid cilia that completely lack dynein arms. These data indicate that WDR92 is a key assembly factor specifically required for the stability of axonemal dynein heavy chains in cytoplasm and suggest that cytoplasmic/IFT dynein heavy chains use a distinct folding pathway.
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Affiliation(s)
- Ramila S. Patel-King
- Department of Molecular Biology and Biophysics, University of Connecticut Health Center, Farmington, CT 06030-3305
| | - Miho Sakato-Antoku
- Department of Molecular Biology and Biophysics, University of Connecticut Health Center, Farmington, CT 06030-3305
| | - Maya Yankova
- Department of Molecular Biology and Biophysics, University of Connecticut Health Center, Farmington, CT 06030-3305
- Electron Microscopy Facility, University of Connecticut Health Center, Farmington, CT 06030-3305
| | - Stephen M. King
- Department of Molecular Biology and Biophysics, University of Connecticut Health Center, Farmington, CT 06030-3305
- Electron Microscopy Facility, University of Connecticut Health Center, Farmington, CT 06030-3305
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Lynham J, Houry WA. The Multiple Functions of the PAQosome: An R2TP- and URI1 Prefoldin-Based Chaperone Complex. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1106:37-72. [DOI: 10.1007/978-3-030-00737-9_4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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12
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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: 42] [Impact Index Per Article: 7.0] [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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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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Muñoz-Hernández H, Pal M, Rodríguez CF, Prodromou C, Pearl LH, Llorca O. Advances on the Structure of the R2TP/Prefoldin-like Complex. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1106:73-83. [DOI: 10.1007/978-3-030-00737-9_5] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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15
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Patel-King RS, King SM. A prefoldin-associated WD-repeat protein (WDR92) is required for the correct architectural assembly of motile cilia. Mol Biol Cell 2016; 27:1204-9. [PMID: 26912790 PMCID: PMC4831875 DOI: 10.1091/mbc.e16-01-0040] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Accepted: 02/08/2016] [Indexed: 11/11/2022] Open
Abstract
WDR92 is a highly conserved WD-repeat protein that has been proposed to be involved in apoptosis and also to be part of a prefoldin-like cochaperone complex. We found that WDR92 has a phylogenetic signature that is generally compatible with it playing a role in the assembly or function of specifically motile cilia. To test this hypothesis, we performed an RNAi-based knockdown of WDR92 gene expression in the planarianSchmidtea mediterraneaand were able to achieve a robust reduction in mRNA expression to levels undetectable under our standard RT-PCR conditions. We found that this treatment resulted in a dramatic reduction in the rate of organismal movement that was caused by a switch in the mode of locomotion from smooth, cilia-driven gliding to muscle-based, peristaltic contractions. Although the knockdown animals still assembled cilia of normal length and in similar numbers to controls, these structures had reduced beat frequency and did not maintain hydrodynamic coupling. By transmission electron microscopy we observed that many cilia had pleiomorphic defects in their architecture, including partial loss of dynein arms, incomplete closure of the B-tubule, and occlusion or replacement of the central pair complex by accumulated electron-dense material. These observations suggest that WDR92 is part of a previously unrecognized cytoplasmic chaperone system that is specifically required to fold key components necessary to build motile ciliary axonemes.
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Affiliation(s)
- Ramila S Patel-King
- Department of Molecular Biology and Biophysics, University of Connecticut Health Center, Farmington, CT 06030-3305
| | - Stephen M King
- Department of Molecular Biology and Biophysics, University of Connecticut Health Center, Farmington, CT 06030-3305 Institute for Systems Genomics, University of Connecticut Health Center, Farmington, CT 06030-3305
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Drosophila spaghetti and doubletime link the circadian clock and light to caspases, apoptosis and tauopathy. PLoS Genet 2015; 11:e1005171. [PMID: 25951229 PMCID: PMC4423883 DOI: 10.1371/journal.pgen.1005171] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Accepted: 03/25/2015] [Indexed: 01/23/2023] Open
Abstract
While circadian dysfunction and neurodegeneration are correlated, the mechanism for this is not understood. It is not known if age-dependent circadian dysfunction leads to neurodegeneration or vice-versa, and the proteins that mediate the effect remain unidentified. Here, we show that the knock-down of a regulator (spag) of the circadian kinase Dbt in circadian cells lowers Dbt levels abnormally, lengthens circadian rhythms and causes expression of activated initiator caspase (Dronc) in the optic lobes during the middle of the day or after light pulses at night. Likewise, reduced Dbt activity lengthens circadian period and causes expression of activated Dronc, and a loss-of-function mutation in Clk also leads to expression of activated Dronc in a light-dependent manner. Genetic epistasis experiments place Dbt downstream of Spag in the pathway, and Spag-dependent reductions of Dbt are shown to require the proteasome. Importantly, activated Dronc expression due to reduced Spag or Dbt activity occurs in cells that do not express the spag RNAi or dominant negative Dbt and requires PDF neuropeptide signaling from the same neurons that support behavioral rhythms. Furthermore, reduction of Dbt or Spag activity leads to Dronc-dependent Drosophila Tau cleavage and enhanced neurodegeneration produced by human Tau in a fly eye model for tauopathy. Aging flies with lowered Dbt or Spag function show markers of cell death as well as behavioral deficits and shortened lifespans, and even old wild type flies exhibit Dbt modification and activated caspase at particular times of day. These results suggest that Dbt suppresses expression of activated Dronc to prevent Tau cleavage, and that the circadian clock defects confer sensitivity to expression of activated Dronc in response to prolonged light. They establish a link between the circadian clock factors, light, cell death pathways and Tau toxicity, potentially via dysregulation of circadian neuronal remodeling in the optic lobes. Alzheimer’s disease is the most common cause of dementia in the aging population. It is a progressive neurodegenerative disorder that attacks the brain neurons, resulting in loss of memory, thinking and behavioral changes. One pathological hallmark is aggregation of the microtubule-associated protein Tau. A growing body of evidence highlights the importance of caspase-dependent Tau truncation in initiation and potentiation of Tau aggregation. Here we use the fruit fly Drosophila to examine the links between circadian rhythms, aging, apoptosis and Alzheimer’s Disease. We identified a regulator (spag) of the circadian kinase Dbt that functions to stabilize Dbt during the middle of the day. In addition, the caspase Dronc is regulated by Dbt and Spag and, when activated by reduction of either, targets Tau for cleavage, leading to behavioral deficits and shortened lifespans. The expression of activated caspase occurs in several parts of the brain in a manner requiring signaling from a neuropeptide produced by circadian cells. Wild type flies with no genetic modifications eventually exhibit modified Dbt and expression of activated caspase at specific times of day, further demonstrating the links between the circadian clock, light and apoptosis.
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Morgan RML, Pal M, Roe SM, Pearl LH, Prodromou C. Tah1 helix-swap dimerization prevents mixed Hsp90 co-chaperone complexes. ACTA CRYSTALLOGRAPHICA. SECTION D, BIOLOGICAL CRYSTALLOGRAPHY 2015; 71:1197-206. [PMID: 25945584 PMCID: PMC4427203 DOI: 10.1107/s1399004715004551] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Accepted: 03/04/2015] [Indexed: 11/12/2022]
Abstract
Specific co-chaperone adaptors facilitate the recruitment of client proteins to the Hsp90 system. Tah1 binds the C-terminal conserved MEEVD motif of Hsp90, thus linking an eclectic set of client proteins to the R2TP complex for their assembly and regulation by Hsp90. Rather than the normal complement of seven α-helices seen in other tetratricopeptide repeat (TPR) domains, Tah1 unusually consists of the first five only. Consequently, the methionine of the MEEVD peptide remains exposed to solvent when bound by Tah1. In solution Tah1 appears to be predominantly monomeric, and recent structures have failed to explain how Tah1 appears to prevent the formation of mixed TPR domain-containing complexes such as Cpr6-(Hsp90)2-Tah1. To understand this further, the crystal structure of Tah1 in complex with the MEEVD peptide of Hsp90 was determined, which shows a helix swap involving the fifth α-helix between two adjacently bound Tah1 molecules. Dimerization of Tah1 restores the normal binding environment of the bound Hsp90 methionine residue by reconstituting a TPR binding site similar to that in seven-helix-containing TPR domain proteins. Dimerization also explains how other monomeric TPR-domain proteins are excluded from forming inappropriate mixed co-chaperone complexes.
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Affiliation(s)
- Rhodri M. L. Morgan
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9RQ, England
| | - Mohinder Pal
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9RQ, England
| | - S. Mark Roe
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9RQ, England
| | - Laurence H. Pearl
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9RQ, England
| | - Chrisostomos Prodromou
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9RQ, England
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18
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Chagot ME, Jacquemin C, Branlant C, Charpentier B, Manival X, Quinternet M. (1)H, (15)N and (13)C resonance assignments of the two TPR domains from the human RPAP3 protein. BIOMOLECULAR NMR ASSIGNMENTS 2015; 9:99-102. [PMID: 24668569 DOI: 10.1007/s12104-014-9552-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Accepted: 03/11/2014] [Indexed: 06/03/2023]
Abstract
We report the nearly complete (1)H, (15)N and (13)C resonance assignments of the two tetratricopeptide-repeat domains of the human RPAP3 protein, a co-chaperone of the heat-shock protein family.
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Affiliation(s)
- Marie-Eve Chagot
- Ingénierie Moléculaire et Physiopathologie Articulaire (IMoPA), UMR 7365 CNRS Université de Lorraine, Biopôle de l'Université de Lorraine, Campus Biologie Santé, 9 avenue de la forêt de Haye, CS 50184, 54505, Vandœuvre-lès-Nancy, France
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19
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von Morgen P, Hořejší Z, Macurek L. Substrate recognition and function of the R2TP complex in response to cellular stress. Front Genet 2015; 6:69. [PMID: 25767478 PMCID: PMC4341119 DOI: 10.3389/fgene.2015.00069] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Accepted: 02/10/2015] [Indexed: 11/18/2022] Open
Abstract
The R2TP complex is a HSP90 co-chaperone, which consists of four subunits: PIH1D1, RPAP3, RUVBL1, and RUVBL2. It is involved in the assembly of large protein or protein–RNA complexes such as RNA polymerase, small nucleolar ribonucleoproteins (snoRNPs), phosphatidylinositol 3 kinase-related kinases (PIKKs), and their complexes. While RPAP3 has a HSP90 binding domain and the RUVBLs comprise ATPase activities important for R2TP functions, PIH1D1 contains a PIH-N domain that specifically recognizes phosphorylated substrates of the R2TP complex. In this review we provide an overview of the current knowledge of the R2TP complex with the focus on the recently identified structural and mechanistic features of the R2TP complex functions. We also discuss the way R2TP regulates cellular response to stress caused by low levels of nutrients or by DNA damage and its possible exploitation as a target for anti-cancer therapy.
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Affiliation(s)
- Patrick von Morgen
- Department of Cancer Cell Biology, Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Prague Czech Republic
| | - Zuzana Hořejší
- Department of Cancer Cell Biology, Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Prague Czech Republic ; DNA Damage Response Laboratory, London Research Institute, London UK
| | - Libor Macurek
- Department of Cancer Cell Biology, Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Prague Czech Republic
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20
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King SM, Patel-King RS. The oligomeric outer dynein arm assembly factor CCDC103 is tightly integrated within the ciliary axoneme and exhibits periodic binding to microtubules. J Biol Chem 2015; 290:7388-401. [PMID: 25572396 DOI: 10.1074/jbc.m114.616425] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
CCDC103 is an ∼29-kDa protein consisting of a central RPAP3_C domain flanked by N- and C-terminal coiled coils. Defects in CCDC103 lead to primary ciliary dyskinesia caused by the loss of outer dynein arms. This protein is present along the entire length of the ciliary axoneme and does not require other dynein or docking complex components for its integration. Unlike other known dynein assembly factors within the axoneme, CCDC103 is not solubilized by 0.6 M NaCl and requires more chaotropic conditions, such as 0.5 M KI. Alternatively, it can be extracted using 0.3% sarkosyl. CCDC103 forms stable dimers and other oligomers in solution through interactions involving the central domain. The smallest particle observed by dynamic light scattering has a hydrodynamic diameter of ∼25 nm. Furthermore, CCDC103 binds microtubules directly, forming ∼9-nm diameter particles that exhibit a 12-nm spacing on the microtubule lattice, suggesting that there may be two CCDC103 units per outer arm dynein repeat. Although the outer dynein arm docking complex is necessary to form arrays of dyneins along microtubules, it is not sufficient to set up a single array in a precise location on each axonemal doublet. We propose that CCDC103 helps generate a high-affinity site on the doublets for outer arm assembly, either through direct interactions or indirectly, perhaps by modifying the underlying microtubule lattice.
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Affiliation(s)
- Stephen M King
- From the Department of Molecular Biology and Biophysics and Institute for Systems Genomics, University of Connecticut Health Center, Farmington, Connecticut 06030-3305
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21
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Benbahouche NEH, Iliopoulos I, Török I, Marhold J, Henri J, Kajava AV, Farkaš R, Kempf T, Schnölzer M, Meyer P, Kiss I, Bertrand E, Mechler BM, Pradet-Balade B. Drosophila Spag is the homolog of RNA polymerase II-associated protein 3 (RPAP3) and recruits the heat shock proteins 70 and 90 (Hsp70 and Hsp90) during the assembly of cellular machineries. J Biol Chem 2014; 289:6236-47. [PMID: 24394412 DOI: 10.1074/jbc.m113.499608] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The R2TP is a recently identified Hsp90 co-chaperone, composed of four proteins as follows: Pih1D1, RPAP3, and the AAA(+)-ATPases RUVBL1 and RUVBL2. In mammals, the R2TP is involved in the biogenesis of cellular machineries such as RNA polymerases, small nucleolar ribonucleoparticles and phosphatidylinositol 3-kinase-related kinases. Here, we characterize the spaghetti (spag) gene of Drosophila, the homolog of human RPAP3. This gene plays an essential function during Drosophila development. We show that Spag protein binds Drosophila orthologs of R2TP components and Hsp90, like its yeast counterpart. Unexpectedly, Spag also interacts and stimulates the chaperone activity of Hsp70. Using null mutants and flies with inducible RNAi, we show that spaghetti is necessary for the stabilization of snoRNP core proteins and target of rapamycin activity and likely the assembly of RNA polymerase II. This work highlights the strong conservation of both the HSP90/R2TP system and its clients and further shows that Spag, unlike Saccharomyces cerevisiae Tah1, performs essential functions in metazoans. Interaction of Spag with both Hsp70 and Hsp90 suggests a model whereby R2TP would accompany clients from Hsp70 to Hsp90 to facilitate their assembly into macromolecular complexes.
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Affiliation(s)
- Nour El Houda Benbahouche
- From the Equipe Labellisée Ligue Contre le Cancer, Institut de Génétique Moléculaire de Montpellier, UMR 5535 CNRS, 1919 Route de Mende, 34293 Montpellier Cedex 5, France
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22
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PIH1D1 interacts with mTOR complex 1 and enhances ribosome RNA transcription. FEBS Lett 2013; 587:3303-8. [DOI: 10.1016/j.febslet.2013.09.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Revised: 08/30/2013] [Accepted: 09/01/2013] [Indexed: 02/07/2023]
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23
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Saeki M, Egusa H, Kamano Y, Kakihara Y, Houry WA, Yatani H, Noguchi S, Kamisaki Y. Exosome-bound WD repeat protein Monad inhibits breast cancer cell invasion by degrading amphiregulin mRNA. PLoS One 2013; 8:e67326. [PMID: 23844004 PMCID: PMC3701000 DOI: 10.1371/journal.pone.0067326] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2013] [Accepted: 05/17/2013] [Indexed: 11/19/2022] Open
Abstract
Increased stabilization of mRNA coding for key cancer genes can contribute to invasiveness. This is achieved by down-regulation of exosome cofactors, which bind to 3'-UTR in cancer-related genes. Here, we identified amphiregulin, an EGFR ligand, as a target of WD repeat protein Monad, a component of R2TP/prefoldin-like complex, in MDA-MB-231 breast cancer cells. Monad specifically interacted with both the 3'-UTR of amphiregulin mRNA and the RNA degrading exosome, and enhanced decay of amphiregulin transcripts. Knockdown of Monad increased invasion and this effect was abolished with anti-amphiregulin neutralizing antibody. These results suggest that Monad could prevent amphiregulin-mediated invasion by degrading amphiregulin mRNA.
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Affiliation(s)
- Makio Saeki
- Department of Pharmacology, Graduate School of Dentistry, Osaka University, Suita, Osaka, Japan.
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Izumi N, Yamashita A, Ohno S. Integrated regulation of PIKK-mediated stress responses by AAA+ proteins RUVBL1 and RUVBL2. Nucleus 2012; 3:29-43. [PMID: 22540023 PMCID: PMC3337166 DOI: 10.4161/nucl.18926] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Proteins of the phosphatidylinositol 3-kinase-related protein kinase (PIKK) family are activated by various cellular stresses, including DNA damage, premature termination codon and nutritional status, and induce appropriate cellular responses. The importance of PIKK functions in the maintenance of genome integrity, accurate gene expression and the proper control of cell growth/proliferation is established. Recently, ATPase associated diverse cellular activities (AAA+) proteins RUVBL1 and RUVBL2 (RUVBL1/2) have been shown to be common regulators of PIKKs. The RUVBL1/2 complex regulates PIKK-mediated stress responses through physical interactions with PIKKs and by controlling PIKK mRNA levels. In this review, the functions of PIKKs in stress responses are outlined and the physiological significance of the integrated regulation of PIKKs by the RUVBL1/2 complex is presented. We also discuss a putative "PIKK regulatory chaperone complex" including other PIKK regulators, Hsp90 and the Tel2 complex.
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Affiliation(s)
- Natsuko Izumi
- Department of Molecular Biology, Yokohama City University School of Medicine, Yokohama, Japan
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25
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Yoshida M, Saeki M, Egusa H, Irie Y, Kamano Y, Uraguchi S, Sotozono M, Niwa H, Kamisaki Y. RPAP3 splicing variant isoform 1 interacts with PIH1D1 to compose R2TP complex for cell survival. Biochem Biophys Res Commun 2012; 430:320-4. [PMID: 23159623 DOI: 10.1016/j.bbrc.2012.11.017] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2012] [Accepted: 11/01/2012] [Indexed: 12/19/2022]
Abstract
We previously characterized RNA polymerase II-associated protein 3 (RPAP3) as a cell death enhancer. Here we report the identification and characterization of splicing isoform of RPAP3, isoform 1 and 2. We investigated the interaction between RPAP3 and PIH1 domain containing protein 1 (PIH1D1), and found that RPAP3 isoform 1, but not isoform 2, interacted with PIH1D1. Furthermore, knockdown of RPAP3 isoform 1 by small interfering RNA down-regulated PIH1D1 protein level without affecting PIH1D1 mRNA. RPAP3 isoform 2 potentiated doxorubicin-induced cell death in human breast cancer T-47 cells although isoform 1 showed no effect. These results suggest that R2TP complex is composed of RPAP3 isoform 1 for its stabilization, and that RPAP3 isoform 2 may have a dominant negative effect on the survival potency of R2TP complex.
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Affiliation(s)
- Miki Yoshida
- Department of Pharmacology, Graduate School of Dentistry, Osaka University, Suita, Osaka 565-0871, Japan
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26
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Kakihara Y, Houry WA. The R2TP complex: Discovery and functions. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2012; 1823:101-7. [DOI: 10.1016/j.bbamcr.2011.08.016] [Citation(s) in RCA: 100] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2011] [Revised: 08/30/2011] [Accepted: 08/30/2011] [Indexed: 10/17/2022]
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Shimada K, Saeki M, Egusa H, Fukuyasu S, Yura Y, Iwai K, Kamisaki Y. RPAP3 enhances cytotoxicity of doxorubicin by impairing NF-kappa B pathway. Biochem Biophys Res Commun 2011; 404:910-4. [DOI: 10.1016/j.bbrc.2010.12.071] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2010] [Accepted: 12/15/2010] [Indexed: 10/18/2022]
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28
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Inoue M, Saeki M, Egusa H, Niwa H, Kamisaki Y. PIH1D1, a subunit of R2TP complex, inhibits doxorubicin-induced apoptosis. Biochem Biophys Res Commun 2010; 403:340-4. [PMID: 21078300 DOI: 10.1016/j.bbrc.2010.11.031] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2010] [Accepted: 11/08/2010] [Indexed: 12/17/2022]
Abstract
We have previously reported that the two components of R2TP complex, RNA polymerase II-associated protein 3 (RPAP3), and Reptin, regulate apoptosis. Here we characterize another component of the complex, PIH1 domain containing protein 1 (PIH1D1). PIH1D1 interacts with both RPAP3 and Monad in HEK293 or U2OS cells. PIH1D1 transcripts were abundant in lung, leukocyte, and placenta. The reduction in endogenous PIH1D1 by siRNA enhanced apoptosis and caspase-3 activation induced by doxorubicin in U2OS cells. These results suggest that PIH1D1 may also function as a novel modulator of apoptosis pathway.
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Affiliation(s)
- Mika Inoue
- Department of Pharmacology, Graduate School of Dentistry, Osaka University, Suita, Osaka, Japan
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29
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Cloutier P, Coulombe B. New insights into the biogenesis of nuclear RNA polymerases? Biochem Cell Biol 2010; 88:211-21. [PMID: 20453924 DOI: 10.1139/o09-173] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
More than 30 years of research on nuclear RNA polymerases (RNAP I, II, and III) has uncovered numerous factors that regulate the activity of these enzymes during the transcription reaction. However, very little is known about the machinery that regulates the fate of RNAPs before or after transcription. In particular, the mechanisms of biogenesis of the 3 nuclear RNAPs, which comprise both common and specific subunits, remains mostly uncharacterized and the proteins involved are yet to be discovered. Using protein affinity purification coupled to mass spectrometry (AP-MS), we recently unraveled a high-density interaction network formed by nuclear RNAP subunits from the soluble fraction of human cell extracts. Validation of the dataset using a machine learning approach trained to minimize the rate of false positives and false negatives yielded a high-confidence dataset and uncovered novel interactors that regulate the RNAP II transcription machinery, including a set of proteins we named the RNAP II-associated proteins (RPAPs). One of the RPAPs, RPAP3, is part of an 11-subunit complex we termed the RPAP3/R2TP/prefoldin-like complex. Here, we review the literature on the subunits of this complex, which points to a role in nuclear RNAP biogenesis.
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Affiliation(s)
- Philippe Cloutier
- Laboratory of Gene Transcription and Proteomics, Institut de recherches cliniques de Montreal, 110 avenue des Pins Ouest, Montreal, QC H2W 1R7, Canada
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30
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Ni L, Saeki M, Xu L, Nakahara H, Saijo M, Tanaka K, Kamisaki Y. RPAP3 interacts with Reptin to regulate UV-induced phosphorylation of H2AX and DNA damage. J Cell Biochem 2009; 106:920-8. [PMID: 19180575 DOI: 10.1002/jcb.22073] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
We have previously reported that Monad, a novel WD40 repeat protein, potentiates apoptosis induced by tumor necrosis factor-alpha and cycloheximide. By affinity purification and mass spectrometry, RNA polymerase II-associated protein 3 (RPAP3) was identified as a Monad binding protein and may function with Monad as a novel modulator of apoptosis pathways. Here we report that Reptin, a highly conserved AAA + ATPase that is part of various chromatin-remodeling complexes, is also involved in the association of RPAP3 by immunoprecipitation and confocal microscopic analysis. Overexpression of RPAP3 induced HEK293 cells to death after UV-irradiation. Loss of RPAP3 by RNAi improved HeLa cell survival after UV-induced DNA damage and attenuated the phosphorylation of H2AX. Depletion of Reptin reduced cell survival and facilitated the phosphorylation on H2AX. These results suggest that RPAP3 modulates UV-induced DNA damage by regulating H2AX phosphorylation.
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Affiliation(s)
- Lin Ni
- Department of Pharmacology, Graduate School of Dentistry, Osaka University, Suita, Osaka, Japan
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Cloutier P, Al-Khoury R, Lavallée-Adam M, Faubert D, Jiang H, Poitras C, Bouchard A, Forget D, Blanchette M, Coulombe B. High-resolution mapping of the protein interaction network for the human transcription machinery and affinity purification of RNA polymerase II-associated complexes. Methods 2009; 48:381-6. [PMID: 19450687 DOI: 10.1016/j.ymeth.2009.05.005] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2008] [Revised: 05/08/2009] [Accepted: 05/11/2009] [Indexed: 10/20/2022] Open
Abstract
Thirty years of research on gene transcription has uncovered a myriad of factors that regulate, directly or indirectly, the activity of RNA polymerase II (RNAPII) during mRNA synthesis. Yet many regulatory factors remain to be discovered. Using protein affinity purification coupled to mass spectrometry (AP-MS), we recently unraveled a high-density interaction network formed by RNAPII and its accessory factors from the soluble fraction of human cell extracts. Validation of the dataset using a machine learning approach trained to minimize the rate of false positives and false negatives yielded a high-confidence dataset and uncovered novel interactors that regulate the RNAPII transcription machinery, including a new protein assembly we named the RNAPII-Associated Protein 3 (RPAP3) complex.
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Affiliation(s)
- Philippe Cloutier
- Institut de recherches cliniques de Montréal, Montréal (Québec), Canada
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