1
|
Yang Y, Zhang G, Su M, Shi Q, Chen Q. Prefoldin Subunits and Its Associate Partners: Conservations and Specificities in Plants. PLANTS (BASEL, SWITZERLAND) 2024; 13:556. [PMID: 38498526 PMCID: PMC10893143 DOI: 10.3390/plants13040556] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Revised: 02/16/2024] [Accepted: 02/17/2024] [Indexed: 03/20/2024]
Abstract
Prefoldins (PFDs) are ubiquitous co-chaperone proteins that originated in archaea during evolution and are present in all eukaryotes, including yeast, mammals, and plants. Typically, prefoldin subunits form hexameric PFD complex (PFDc) that, together with class II chaperonins, mediate the folding of nascent proteins, such as actin and tubulin. In addition to functioning as a co-chaperone in cytoplasm, prefoldin subunits are also localized in the nucleus, which is essential for transcription and post-transcription regulation. However, the specific and critical roles of prefoldins in plants have not been well summarized. In this review, we present an overview of plant prefoldin and its related proteins, summarize the structure of prefoldin/prefoldin-like complex (PFD/PFDLc), and analyze the versatile landscape by prefoldin subunits, from cytoplasm to nucleus regulation. We also focus the specific role of prefoldin-mediated phytohormone response and global plant development. Finally, we overview the emerging prefoldin-like (PFDL) subunits in plants and the novel roles in related processes, and discuss the next direction in further studies.
Collapse
Affiliation(s)
- Yi Yang
- Shandong Provincial Key Laboratory of Biophysics, Institute of Biophysics, Dezhou University, Dezhou 253023, China; (G.Z.); (M.S.)
| | - Gang Zhang
- Shandong Provincial Key Laboratory of Biophysics, Institute of Biophysics, Dezhou University, Dezhou 253023, China; (G.Z.); (M.S.)
| | - Mengyu Su
- Shandong Provincial Key Laboratory of Biophysics, Institute of Biophysics, Dezhou University, Dezhou 253023, China; (G.Z.); (M.S.)
| | - Qingbiao Shi
- National Key Laboratory of Wheat Improvement, College of Life Sciences, Shandong Agricultural University, Tai’an 271018, China;
| | - Qingshuai Chen
- Shandong Provincial Key Laboratory of Biophysics, Institute of Biophysics, Dezhou University, Dezhou 253023, China; (G.Z.); (M.S.)
| |
Collapse
|
2
|
Pinard M, Moursli A, Coulombe B. Drugs targeting the particle for arrangement of quaternary structure (PAQosome) and protein complex assembly. Expert Opin Drug Discov 2024; 19:57-71. [PMID: 37840283 DOI: 10.1080/17460441.2023.2267974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Accepted: 10/04/2023] [Indexed: 10/17/2023]
Abstract
INTRODUCTION The PAQosome is a 12-subunit complex that acts as a co-factor of the molecular chaperones HSP90 and HSP70. This co-chaperone has been shown to participate in assembly and maturation of several protein complexes, including nuclear RNA polymerases, RNA processing factors, the ribosome, PIKKs, and others. Subunits of the PAQosome, adaptors, and clients have been reported to be involved in various diseases, making them interesting targets for drug discovery. AREA COVERED In this review, the authors cover the detailed mechanisms of PAQosome and chaperone function. Specifically, the authors summarize the status of the PAQosome and some related chaperones and co-chaperones as candidate targets for drug discovery. Indeed, a number of compounds are currently being tested for the development of treatments against diseases, such as cancers and neurodegenerative conditions. EXPERT OPINION Searching for new drugs targeting the PAQosome requires a better understanding of PAQosome subunit interactions and the discovery of new interaction partners. Thus, PAQosome subunit crystallization is an important experiment to initiate virtual screening against new target and the development of in silico tools such as AlphaFold-multimer could accelerate the search for new interaction partner and determine more rapidly the interaction pocket needed for virtual drug screening.
Collapse
Affiliation(s)
- Maxime Pinard
- Translational Proteomics Laboratory, Institut de Recherches Cliniques de Montréal, Montréal, Québec, Canada
| | - Asmae Moursli
- Translational Proteomics Laboratory, Institut de Recherches Cliniques de Montréal, Montréal, Québec, Canada
| | - Benoit Coulombe
- Translational Proteomics Laboratory, Institut de Recherches Cliniques de Montréal, Montréal, Québec, Canada
- Department of Biochemistry and Molecular Medicine, Université de Montréal, Montréal, Québec, Canada
| |
Collapse
|
3
|
Zhao H, Chen C, Yang C, Mo S, Zhao H, Tian Y. Prefoldin and prefoldin-like complex subunits as predictive biomarkers for hepatocellular carcinoma immunotherapy. Pathol Res Pract 2022; 232:153808. [DOI: 10.1016/j.prp.2022.153808] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 02/09/2022] [Accepted: 02/11/2022] [Indexed: 12/15/2022]
|
4
|
Toullec D, Elías-Villalobos A, Faux C, Noly A, Lledo G, Séveno M, Helmlinger D. The Hsp90 cochaperone TTT promotes cotranslational maturation of PIKKs prior to complex assembly. Cell Rep 2021; 37:109867. [PMID: 34686329 DOI: 10.1016/j.celrep.2021.109867] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 07/30/2021] [Accepted: 09/30/2021] [Indexed: 01/28/2023] Open
Abstract
Phosphatidylinositol 3-kinase-related kinases (PIKKs) are a family of kinases that control fundamental processes, including cell growth, DNA damage repair, and gene expression. Although their regulation and activities are well characterized, little is known about how PIKKs fold and assemble into active complexes. Previous work has identified a heat shock protein 90 (Hsp90) cochaperone, the TTT complex, that specifically stabilizes PIKKs. Here, we describe a mechanism by which TTT promotes their de novo maturation in fission yeast. We show that TTT recognizes newly synthesized PIKKs during translation. Although PIKKs form multimeric complexes, we find that they do not engage in cotranslational assembly with their partners. Rather, our findings suggest a model by which TTT protects nascent PIKK polypeptides from misfolding and degradation because PIKKs acquire their native state after translation is terminated. Thus, PIKK maturation and assembly are temporally segregated, suggesting that the biogenesis of large complexes requires both dedicated chaperones and cotranslational interactions between subunits.
Collapse
Affiliation(s)
- Damien Toullec
- CRBM, University of Montpellier, CNRS, Montpellier, France
| | | | - Céline Faux
- CRBM, University of Montpellier, CNRS, Montpellier, France
| | - Ambre Noly
- CRBM, University of Montpellier, CNRS, Montpellier, France
| | | | - Martial Séveno
- BioCampus Montpellier, University of Montpellier, CNRS, INSERM, Montpellier, France
| | | |
Collapse
|
5
|
Pal M, Muñoz-Hernandez H, Bjorklund D, Zhou L, Degliesposti G, Skehel JM, Hesketh EL, Thompson RF, Pearl LH, Llorca O, Prodromou C. Structure of the TELO2-TTI1-TTI2 complex and its function in TOR recruitment to the R2TP chaperone. Cell Rep 2021; 36:109317. [PMID: 34233195 PMCID: PMC8278493 DOI: 10.1016/j.celrep.2021.109317] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 03/15/2021] [Accepted: 06/07/2021] [Indexed: 11/28/2022] Open
Abstract
The R2TP (RUVBL1-RUVBL2-RPAP3-PIH1D1) complex, in collaboration with heat shock protein 90 (HSP90), functions as a chaperone for the assembly and stability of protein complexes, including RNA polymerases, small nuclear ribonucleoprotein particles (snRNPs), and phosphatidylinositol 3-kinase (PI3K)-like kinases (PIKKs) such as TOR and SMG1. PIKK stabilization depends on an additional complex of TELO2, TTI1, and TTI2 (TTT), whose structure and function are poorly understood. The cryoelectron microscopy (cryo-EM) structure of the human R2TP-TTT complex, together with biochemical experiments, reveals the mechanism of TOR recruitment to the R2TP-TTT chaperone. The HEAT-repeat TTT complex binds the kinase domain of TOR, without blocking its activity, and delivers TOR to the R2TP chaperone. In addition, TTT regulates the R2TP chaperone by inhibiting RUVBL1-RUVBL2 ATPase activity and by modulating the conformation and interactions of the PIH1D1 and RPAP3 components of R2TP. Taken together, our results show how TTT couples the recruitment of TOR to R2TP with the regulation of this chaperone system.
Collapse
Affiliation(s)
- Mohinder Pal
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9RQ, UK
| | - Hugo Muñoz-Hernandez
- Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, 28029 Madrid, Spain
| | - Dennis Bjorklund
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9RQ, UK
| | - Lihong Zhou
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9RQ, UK
| | - Gianluca Degliesposti
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge CB2 0QH, UK
| | - J Mark Skehel
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge CB2 0QH, UK
| | - Emma L Hesketh
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Rebecca F Thompson
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Laurence H Pearl
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9RQ, UK; Division of Structural Biology, Institute of Cancer Research, Chester Beatty Laboratories, 237 Fulham Road, London SW1E 6BT, UK.
| | - Oscar Llorca
- Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, 28029 Madrid, Spain.
| | - Chrisostomos Prodromou
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9RQ, UK
| |
Collapse
|
6
|
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.
Collapse
|
7
|
Nakamura A, Kakihara Y, Funayama A, Haga K, Mikami T, Kobayashi D, Yoshida Y, Izumi K, Kobayashi T, Saeki M. HEATR1, a novel interactor of Pontin/Reptin, stabilizes Pontin/Reptin and promotes cell proliferation of oral squamous cell carcinoma. Biochem Biophys Res Commun 2021; 557:294-301. [PMID: 33894417 DOI: 10.1016/j.bbrc.2021.04.021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 04/07/2021] [Indexed: 12/25/2022]
Abstract
Pontin and Reptin are closely related proteins belonging to the AAA+ (ATPases Associated with various cellular Activities) family. They form a hetero-oligomeric complex, Pontin/Reptin, which is involved in protein stability and assembly of the protein complexes as a molecular chaperone. Overexpression of Pontin and Reptin in tumor cells has been reported and is implicated in the development of various cancers. However, the molecular mechanism of Pontin/Reptin function in oral squamous cell carcinoma (OSCC) development remains unclear. Here, we identify HEAT repeat-containing protein 1 (HEATR1) as a novel binding factor of Pontin/Reptin. Functionally, HEATR1 stabilizes Pontin/Reptin and positively regulates OSCC cell proliferation by activating mTOR and pre-rRNA synthesis. We also find that HEATR1 expression is markedly upregulated in tumor region of OSCC tissue. Hence, we propose that HEATR1 is involved in the regulation of mTOR and ribosome biogenesis as a potential protein stabilizer of Pontin/Reptin in OSCC.
Collapse
Affiliation(s)
- Akihiko Nakamura
- Division of Reconstructive Surgery for Oral and Maxillofacial Region, Faculty of Dentistry & Graduate School of Medical and Dental Sciences, Niigata University, 2-5274 Gakkocho-dori, Chuo-ku, Niigata, 951-8514, Japan; Division of Dental Pharmacology, Faculty of Dentistry & Graduate School of Medical and Dental Sciences, Niigata University, 2-5274 Gakkocho-dori, Chuo-ku, Niigata, 951-8514, Japan
| | - Yoshito Kakihara
- Division of Dental Pharmacology, Faculty of Dentistry & Graduate School of Medical and Dental Sciences, Niigata University, 2-5274 Gakkocho-dori, Chuo-ku, Niigata, 951-8514, Japan.
| | - Akinori Funayama
- Division of Reconstructive Surgery for Oral and Maxillofacial Region, Faculty of Dentistry & Graduate School of Medical and Dental Sciences, Niigata University, 2-5274 Gakkocho-dori, Chuo-ku, Niigata, 951-8514, Japan
| | - Kenta Haga
- Division of Reconstructive Surgery for Oral and Maxillofacial Region, Faculty of Dentistry & Graduate School of Medical and Dental Sciences, Niigata University, 2-5274 Gakkocho-dori, Chuo-ku, Niigata, 951-8514, Japan
| | - Toshihiko Mikami
- Division of Reconstructive Surgery for Oral and Maxillofacial Region, Faculty of Dentistry & Graduate School of Medical and Dental Sciences, Niigata University, 2-5274 Gakkocho-dori, Chuo-ku, Niigata, 951-8514, Japan
| | - Daiki Kobayashi
- Omics Unit, Niigata University Graduate School of Medical and Dental Sciences, 1-757 Asahimachi-dori, Chuo-ku, Niigata, 951-8510, Japan
| | - Yutaka Yoshida
- Department of Structural Pathology, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, 1-757 Asahimachi-dori, Chuo-ku, Niigata, 951-8510, Japan
| | - Kenji Izumi
- Division of Biomimetics, Faculty of Dentistry & Graduate School of Medical and Dental Sciences, Niigata University, 2-5274 Gakkocho-dori, Chuo-ku, Niigata, 951-8514, Japan
| | - Tadaharu Kobayashi
- Division of Reconstructive Surgery for Oral and Maxillofacial Region, Faculty of Dentistry & Graduate School of Medical and Dental Sciences, Niigata University, 2-5274 Gakkocho-dori, Chuo-ku, Niigata, 951-8514, Japan
| | - Makio Saeki
- Division of Dental Pharmacology, Faculty of Dentistry & Graduate School of Medical and Dental Sciences, Niigata University, 2-5274 Gakkocho-dori, Chuo-ku, Niigata, 951-8514, Japan
| |
Collapse
|
8
|
Dafinger C, Benzing T, Dötsch J, Schermer B, Liebau MC. Targeted deletion of Ruvbl1 results in severe defects of epidermal development and perinatal mortality. Mol Cell Pediatr 2021; 8:1. [PMID: 33580312 PMCID: PMC7881068 DOI: 10.1186/s40348-021-00111-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Accepted: 01/26/2021] [Indexed: 11/29/2022] Open
Abstract
Epidermal development is a complex process of regulated cellular proliferation, differentiation, and tightly controlled cell death involving multiple cellular signaling networks. Here, we report a first description linking the AAA+ (ATPases associated with various cellular activities) superfamily protein Ruvbl1 to mammalian epidermal development. Keratinocyte-specific Ruvbl1 knockout mice (Ruvbl1fl/flK14:Cretg) show a severe phenotype including dramatic structural epidermal defects resulting in the loss of the functional skin barrier and perinatal death. Thus, Ruvbl1 is a newly identified essential player for the development of differentiated epidermis in mice.
Collapse
Affiliation(s)
- Claudia Dafinger
- Department of Pediatrics, Faculty of Medicine and University Hospital Cologne, University of Cologne, Kerpener Str. 62, 50937, Cologne, Germany.,Department II of Internal Medicine, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany.,CECAD, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Thomas Benzing
- Department II of Internal Medicine, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany.,CECAD, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany.,Systems Biology of Ageing Cologne, University of Cologne, Cologne, Germany.,Center for Molecular Medicine, University of Cologne, Cologne, Germany
| | - Jörg Dötsch
- Department of Pediatrics, Faculty of Medicine and University Hospital Cologne, University of Cologne, Kerpener Str. 62, 50937, Cologne, Germany
| | - Bernhard Schermer
- Department II of Internal Medicine, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany.,CECAD, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany.,Systems Biology of Ageing Cologne, University of Cologne, Cologne, Germany.,Center for Molecular Medicine, University of Cologne, Cologne, Germany
| | - Max C Liebau
- Department of Pediatrics, Faculty of Medicine and University Hospital Cologne, University of Cologne, Kerpener Str. 62, 50937, Cologne, Germany. .,Department II of Internal Medicine, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany. .,Center for Molecular Medicine, University of Cologne, Cologne, Germany.
| |
Collapse
|
9
|
Zimmermann F, Serna M, Ezquerra A, Fernandez-Leiro R, Llorca O, Luders J. Assembly of the asymmetric human γ-tubulin ring complex by RUVBL1-RUVBL2 AAA ATPase. SCIENCE ADVANCES 2020; 6:eabe0894. [PMID: 33355144 PMCID: PMC11206223 DOI: 10.1126/sciadv.abe0894] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Accepted: 11/11/2020] [Indexed: 06/12/2023]
Abstract
The microtubule nucleator γ-tubulin ring complex (γTuRC) is essential for the function of microtubule organizing centers such as the centrosome. Since its discovery over two decades ago, γTuRC has evaded in vitro reconstitution and thus detailed structure-function studies. Here, we show that a complex of RuvB-like protein 1 (RUVBL1) and RUVBL2 "RUVBL" controls assembly and composition of γTuRC in human cells. Likewise, RUVBL assembles γTuRC from a minimal set of core subunits in a heterologous coexpression system. RUVBL interacts with γTuRC subcomplexes but is not part of fully assembled γTuRC. Purified, reconstituted γTuRC has nucleation activity and resembles native γTuRC as revealed by its cryo-electron microscopy (cryo-EM) structure at ~4.0-Å resolution. We further use cryo-EM to identify features that determine the intricate, higher-order γTuRC architecture. Our work finds RUVBL as an assembly factor that regulates γTuRC in cells and allows production of recombinant γTuRC for future in-depth mechanistic studies.
Collapse
Affiliation(s)
- Fabian Zimmermann
- Mechanisms of Disease Programme, Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Marina Serna
- Structural Biology Programme, Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, 28029 Madrid, Spain
| | - Artur Ezquerra
- Mechanisms of Disease Programme, Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Rafael Fernandez-Leiro
- Structural Biology Programme, Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, 28029 Madrid, Spain
| | - Oscar Llorca
- Structural Biology Programme, Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, 28029 Madrid, Spain.
| | - Jens Luders
- Mechanisms of Disease Programme, Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), Baldiri Reixac 10, 08028 Barcelona, Spain.
| |
Collapse
|
10
|
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.
Collapse
Affiliation(s)
| | - Oscar Llorca
- Correspondence: ; Tel.: +34-91-732-8000 (ext. 3000/3033)
| |
Collapse
|
11
|
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.
Collapse
|