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Martín-Villanueva S, Galmozzi CV, Ruger-Herreros C, Kressler D, de la Cruz J. The Beak of Eukaryotic Ribosomes: Life, Work and Miracles. Biomolecules 2024; 14:882. [PMID: 39062596 PMCID: PMC11274626 DOI: 10.3390/biom14070882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2024] [Revised: 07/19/2024] [Accepted: 07/21/2024] [Indexed: 07/28/2024] Open
Abstract
Ribosomes are not totally globular machines. Instead, they comprise prominent structural protrusions and a myriad of tentacle-like projections, which are frequently made up of ribosomal RNA expansion segments and N- or C-terminal extensions of ribosomal proteins. This is more evident in higher eukaryotic ribosomes. One of the most characteristic protrusions, present in small ribosomal subunits in all three domains of life, is the so-called beak, which is relevant for the function and regulation of the ribosome's activities. During evolution, the beak has transitioned from an all ribosomal RNA structure (helix h33 in 16S rRNA) in bacteria, to an arrangement formed by three ribosomal proteins, eS10, eS12 and eS31, and a smaller h33 ribosomal RNA in eukaryotes. In this review, we describe the different structural and functional properties of the eukaryotic beak. We discuss the state-of-the-art concerning its composition and functional significance, including other processes apparently not related to translation, and the dynamics of its assembly in yeast and human cells. Moreover, we outline the current view about the relevance of the beak's components in human diseases, especially in ribosomopathies and cancer.
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Affiliation(s)
- Sara Martín-Villanueva
- Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, E-41013 Seville, Spain; (S.M.-V.); (C.V.G.); (C.R.-H.)
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla, E-41012 Seville, Spain
| | - Carla V. Galmozzi
- Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, E-41013 Seville, Spain; (S.M.-V.); (C.V.G.); (C.R.-H.)
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla, E-41012 Seville, Spain
| | - Carmen Ruger-Herreros
- Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, E-41013 Seville, Spain; (S.M.-V.); (C.V.G.); (C.R.-H.)
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla, E-41012 Seville, Spain
| | - Dieter Kressler
- Department of Biology, University of Fribourg, CH-1700 Fribourg, Switzerland;
| | - Jesús de la Cruz
- Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, E-41013 Seville, Spain; (S.M.-V.); (C.V.G.); (C.R.-H.)
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla, E-41012 Seville, Spain
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Das AS, Basu A, Mukhopadhyay R. Ribosomal proteins: the missing piece in the inflammation puzzle? Mol Cell Biochem 2024:10.1007/s11010-024-05050-9. [PMID: 38951378 DOI: 10.1007/s11010-024-05050-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2024] [Accepted: 06/09/2024] [Indexed: 07/03/2024]
Abstract
Ribosomal proteins (RPs) are constituents of macromolecular machinery, ribosome that translates genetic information into proteins. Besides ribosomal functions, RPs are now getting appreciated for their 'moonlighting'/extra-ribosomal functions modulating many cellular processes. Accumulating evidence suggests that a number of RPs are involved in inflammation. Though acute inflammation is a part of the innate immune response, uncontrolled inflammation is a driving factor for several chronic inflammatory diseases. An in-depth understanding of inflammation regulation has always been valued for the better management of associated diseases. Hence, this review first outlines the common livelihood of RPs and then provides a comprehensive account of five RPs that significantly contribute to the inflammation process. Finally, we discuss the possible therapeutic uses of RPs against chronic inflammatory diseases.
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Affiliation(s)
- Anindhya Sundar Das
- Department of Molecular Biology and Biotechnology, Tezpur University, Assam, 784028, India.
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, Rhode Island, 02912, USA.
| | - Anandita Basu
- Department of Molecular Biology and Biotechnology, Tezpur University, Assam, 784028, India
- Division of Surgical Research, Department of Surgery, Rhode Island Hospital, The Warren Alpert Medical School of Brown University, Providence, Rhode Island, 02903, USA
| | - Rupak Mukhopadhyay
- Department of Molecular Biology and Biotechnology, Tezpur University, Assam, 784028, India.
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Chen G, Gao X, Jia X, Wang Y, Xu L, Yu D, Chang S, Deng H, Hu K, Wang G, Li B, Xu Z, Lu Y, Wang H, Zhang T, Song D, Yang G, Wu X, Zhu H, Zhu W, Shi J. Ribosomal protein S3 mediates drug resistance of proteasome inhibitor: potential therapeutic application in multiple myeloma. Haematologica 2024; 109:1206-1219. [PMID: 37767568 PMCID: PMC10985453 DOI: 10.3324/haematol.2023.282789] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 09/15/2023] [Indexed: 09/29/2023] Open
Abstract
Multiple myeloma (MM) remains incurable due to drug resistance. Ribosomal protein S3 (RPS3) has been identified as a non-Rel subunit of NF-κB. However, the detailed biological roles of RPS3 remain unclear. Here, we report for the first time that RPS3 is necessary for MM survival and drug resistance. RPS3 was highly expressed in MM, and knockout of RPS3 in MM inhibited cell growth and induced cell apoptosis both in vitro and in vivo. Overexpression of RPS3 mediated the proteasome inhibitor resistance of MM and shortened the survival of MM tumor-bearing animals. Moreover, our present study found an interaction between RPS3 and the thyroid hormone receptor interactor 13 (TRIP13), an oncogene related to MM tumorigenesis and drug resistance. We demonstrated that the phosphorylation of RPS3 was mediated by TRIP13 via PKCδ, which played an important role in activating the canonical NF-κB signaling and inducing cell survival and drug resistance in MM. Notably, the inhibition of NF-κB signaling by the small-molecule inhibitor targeting TRIP13, DCZ0415, was capable of triggering synergistic cytotoxicity when combined with bortezomib in drug-resistant MM. This study identifies RPS3 as a novel biomarker and therapeutic target in MM.
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Affiliation(s)
- Gege Chen
- Department of Hematology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai 200120
| | - Xuejie Gao
- Department of Hematology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai 200120
| | - Xinyan Jia
- Department of Hematology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai 200120
| | - Yingcong Wang
- Department of Hematology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai 200072
| | - Li Xu
- Department of Hematology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai 200120
| | - Dandan Yu
- Department of Hematology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai 200072
| | - Shuaikang Chang
- Department of Hematology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai 200120
| | - Hui Deng
- Department of Hematology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai 200120
| | - Ke Hu
- Department of Hematology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai 200120
| | - Guanli Wang
- Department of Hematology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai 200120
| | - Bo Li
- CAS Key Laboratory of Receptor Research; State Key Laboratory of Drug Research; Drug Discovery and Design Center, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203
| | - Zhijian Xu
- CAS Key Laboratory of Receptor Research; State Key Laboratory of Drug Research; Drug Discovery and Design Center, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203
| | - Yumeng Lu
- Department of Hematology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai 200072
| | - Huaping Wang
- Department of Hematology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai 200072
| | - Ting Zhang
- Department of Hematology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai 200072
| | - Dongliang Song
- Department of Hematology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai 200072
| | - Guang Yang
- Department of Hematology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai 200072
| | - Xiaosong Wu
- Department of Hematology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai 200072
| | - Huabin Zhu
- Department of Hematology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai 200072
| | - Weiliang Zhu
- CAS Key Laboratory of Receptor Research; State Key Laboratory of Drug Research; Drug Discovery and Design Center, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203.
| | - Jumei Shi
- Department of Hematology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai 200120.
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Jin S, Xiong Y, Zhang W, Qiao H, Wu Y, Jiang S, Fu H. Identification of Candidate Male-Reproduction-Related Genes from the Testis and Androgenic Gland of Macrobrachium nipponense, Regulated by PDHE1, through Transcriptome Profiling Analysis. Int J Mol Sci 2024; 25:1940. [PMID: 38339218 PMCID: PMC10856083 DOI: 10.3390/ijms25031940] [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: 01/05/2024] [Revised: 01/27/2024] [Accepted: 01/31/2024] [Indexed: 02/12/2024] Open
Abstract
The previous publication identified that pyruvate dehydrogenase E1 (PDHE1) positively regulated the process of male reproduction in M. nipponense through affecting the expressions of insulin-like androgenic gland hormone. The present study aimed to identify the potential male-reproduction-related genes that were regulated by PDHE1 through performing the transcriptome profiling analysis in the testis and androgenic gland after the knockdown of the expressions of PDHE1 by the injection of dsPDHE1. Both RNA-Seq and qPCR analysis identified the significant decreases in PDHE1 expressions in the testis and androgenic gland in dsPDHE1-injected prawns compared to those in dsGFP-injected prawns, indicating the efficiency of dsPDHE1 in the present study. Transcriptome profiling analysis identified 56 and 127 differentially expressed genes (DEGs) in the testis and androgenic gland, respectively. KEGG analysis revealed that the energy-metabolism-related pathways represented the main enriched metabolic pathways of DEGs in both the testis and androgenic gland, including pyruvate metabolism, the Citrate cycle (TCA cycle), Glycolysis/Gluconeogenesis, and the Glucagon signaling pathway. Thus, it is predicted that these metabolic pathways and the DEGs from these metabolic pathways regulated by PDHE1 may be involved in the regulation of male reproduction in M. nipponense. Furthermore, four genes were found to be differentially expressed in both the testis and androgenic gland, of which ribosomal protein S3 was down-regulated and uncharacterized protein LOC113829596 was up-regulated in both the testis and androgenic gland in dsPDHE1-injected prawns. The present study provided valuable evidence for the establishment of an artificial technique to regulate the process of male reproduction in M. nipponense.
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Affiliation(s)
- Shubo Jin
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China; (Y.X.); (W.Z.); (H.Q.); (Y.W.); (S.J.)
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi 214081, China
| | - Yiwei Xiong
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China; (Y.X.); (W.Z.); (H.Q.); (Y.W.); (S.J.)
| | - Wenyi Zhang
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China; (Y.X.); (W.Z.); (H.Q.); (Y.W.); (S.J.)
| | - Hui Qiao
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China; (Y.X.); (W.Z.); (H.Q.); (Y.W.); (S.J.)
| | - Yan Wu
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China; (Y.X.); (W.Z.); (H.Q.); (Y.W.); (S.J.)
| | - Sufei Jiang
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China; (Y.X.); (W.Z.); (H.Q.); (Y.W.); (S.J.)
| | - Hongtuo Fu
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China; (Y.X.); (W.Z.); (H.Q.); (Y.W.); (S.J.)
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi 214081, China
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5
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Blomqvist EK, Huang H, Karbstein K. A disease associated mutant reveals how Ltv1 orchestrates RP assembly and rRNA folding of the small ribosomal subunit head. PLoS Genet 2023; 19:e1010862. [PMID: 37910572 PMCID: PMC10695388 DOI: 10.1371/journal.pgen.1010862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 12/04/2023] [Accepted: 09/25/2023] [Indexed: 11/03/2023] Open
Abstract
Ribosomes are complex macromolecules assembled from 4 rRNAs and 79 ribosomal proteins (RPs). Their assembly is organized in a highly hierarchical manner, which is thought to avoid dead-end pathways, thereby enabling efficient assembly of ribosomes in the large quantities needed for healthy cellular growth. Moreover, hierarchical assembly also can help ensure that each RP is included in the mature ribosome. Nonetheless, how this hierarchy is achieved remains unknown, beyond the examples that depend on direct RP-RP interactions, which account for only a fraction of the observed dependencies. Using assembly of the small subunit head and a disease-associated mutation in the assembly factor Ltv1 as a model system, we dissect here how the hierarchy in RP binding is constructed. A combination of data from yeast genetics, mass spectrometry, DMS probing and biochemical experiments demonstrate that the LIPHAK-disease-associated Ltv1 mutation leads to global defects in head assembly, which are explained by direct binding of Ltv1 to 5 out of 15 RPs, and indirect effects that affect 4 additional RPs. These indirect effects are mediated by conformational transitions in the nascent subunit that are regulated by Ltv1. Mechanistically, Ltv1 aids the recruitment of some RPs via direct protein-protein interactions, but surprisingly also delays the recruitment of other RPs. Delayed binding of key RPs also delays the acquisition of RNA structure that is stabilized by these proteins. Finally, our data also indicate direct roles for Ltv1 in chaperoning the folding of a key rRNA structural element, the three-helix junction j34-35-38. Thus, Ltv1 plays critical roles in organizing the order of both RP binding to rRNA and rRNA folding, thereby enabling efficient 40S subunit assembly.
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Affiliation(s)
- Ebba K. Blomqvist
- Department of Integrative Structural and Computational Biology, The Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, Florida, United States of America
| | - Haina Huang
- Department of Integrative Structural and Computational Biology, The Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, Florida, United States of America
- The Skaggs Graduate School of Chemical and Biological Sciences, The Scripps Research Institute, La Jolla, California, United States of America
| | - Katrin Karbstein
- Department of Integrative Structural and Computational Biology, The Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, Florida, United States of America
- The Skaggs Graduate School of Chemical and Biological Sciences, The Scripps Research Institute, La Jolla, California, United States of America
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Steiner A, Favre S, Mack M, Hausharter A, Pillet B, Hafner J, Mitterer V, Kressler D, Pertschy B, Zierler I. Dissecting the Nuclear Import of the Ribosomal Protein Rps2 (uS5). Biomolecules 2023; 13:1127. [PMID: 37509163 PMCID: PMC10377357 DOI: 10.3390/biom13071127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 07/06/2023] [Accepted: 07/12/2023] [Indexed: 07/30/2023] Open
Abstract
The ribosome is assembled in a complex process mainly taking place in the nucleus. Consequently, newly synthesized ribosomal proteins have to travel from the cytoplasm into the nucleus, where they are incorporated into nascent ribosomal subunits. In this study, we set out to investigate the mechanism mediating nuclear import of the small subunit ribosomal protein Rps2. We demonstrate that an internal region in Rps2, ranging from amino acids 76 to 145, is sufficient to target a 3xyEGFP reporter to the nucleus. The importin-β Pse1 interacts with this Rps2 region and is involved in its import, with Rps2 residues arginine 95, arginine 97, and lysine 99 being important determinants for both Pse1 binding and nuclear localization. Moreover, our data reveal a second import mechanism involving the N-terminal region of Rps2, which depends on the presence of basic residues within amino acids 10 to 28. This Rps2 segment overlaps with the binding site of the dedicated chaperone Tsr4; however, the nuclear import of Rps2 via the internal as well as the N-terminal nuclear-targeting element does not depend on Tsr4. Taken together, our study has unveiled hitherto undescribed nuclear import signals, showcasing the versatility of the mechanisms coordinating the nuclear import of ribosomal proteins.
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Affiliation(s)
- Andreas Steiner
- Institute of Molecular Biosciences, University of Graz, Humboldtstrasse 50, 8010 Graz, Austria; (A.S.); (M.M.); (V.M.)
- BioTechMed-Graz, Mozartgasse 12/II, 8010 Graz, Austria
| | - Sébastien Favre
- Unit of Biochemistry, Department of Biology, University of Fribourg, Chemin du Musée 10, 1700 Fribourg, Switzerland; (S.F.); (B.P.); (D.K.)
| | - Maximilian Mack
- Institute of Molecular Biosciences, University of Graz, Humboldtstrasse 50, 8010 Graz, Austria; (A.S.); (M.M.); (V.M.)
- BioTechMed-Graz, Mozartgasse 12/II, 8010 Graz, Austria
| | - Annika Hausharter
- Institute of Molecular Biosciences, University of Graz, Humboldtstrasse 50, 8010 Graz, Austria; (A.S.); (M.M.); (V.M.)
| | - Benjamin Pillet
- Unit of Biochemistry, Department of Biology, University of Fribourg, Chemin du Musée 10, 1700 Fribourg, Switzerland; (S.F.); (B.P.); (D.K.)
| | - Jutta Hafner
- Institute of Molecular Biosciences, University of Graz, Humboldtstrasse 50, 8010 Graz, Austria; (A.S.); (M.M.); (V.M.)
- BioTechMed-Graz, Mozartgasse 12/II, 8010 Graz, Austria
| | - Valentin Mitterer
- Institute of Molecular Biosciences, University of Graz, Humboldtstrasse 50, 8010 Graz, Austria; (A.S.); (M.M.); (V.M.)
- BioTechMed-Graz, Mozartgasse 12/II, 8010 Graz, Austria
| | - Dieter Kressler
- Unit of Biochemistry, Department of Biology, University of Fribourg, Chemin du Musée 10, 1700 Fribourg, Switzerland; (S.F.); (B.P.); (D.K.)
| | - Brigitte Pertschy
- Institute of Molecular Biosciences, University of Graz, Humboldtstrasse 50, 8010 Graz, Austria; (A.S.); (M.M.); (V.M.)
- BioTechMed-Graz, Mozartgasse 12/II, 8010 Graz, Austria
| | - Ingrid Zierler
- Institute of Molecular Biosciences, University of Graz, Humboldtstrasse 50, 8010 Graz, Austria; (A.S.); (M.M.); (V.M.)
- BioTechMed-Graz, Mozartgasse 12/II, 8010 Graz, Austria
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7
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Blomqvist EK, Huang H, Karbstein K. A disease associated mutant reveals how Ltv1 orchestrates RP assembly and rRNA folding of the small ribosomal subunit head. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.10.548325. [PMID: 37503067 PMCID: PMC10369890 DOI: 10.1101/2023.07.10.548325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Ribosomes are complex macromolecules assembled from 4 rRNAs and 79 ribosomal proteins (RPs). Their assembly is organized in a highly hierarchical manner, which is thought to avoid dead-end pathways, thereby enabling efficient assembly of ribosomes in the large quantities needed for healthy cellular growth. Moreover, hierarchical assembly also can help ensure that each RP is included in the mature ribosome. Nonetheless, how this hierarchy is achieved remains unknown, beyond the examples that depend on direct RP-RP interactions, which account for only a fraction of the observed dependencies. Using assembly of the small subunit head and a disease-associated mutation in the assembly factor Ltv1 as a model system, we dissect here how the hierarchy in RP binding is constructed. Our data demonstrate that the LIPHAK-disease-associated Ltv1 mutation leads to global defects in head assembly, which are explained by direct binding of Ltv1 to 5 out of 15 RPs, and indirect effects that affect 4 additional RPs. These indirect effects are mediated by conformational transitions in the nascent subunit that are regulated by Ltv1. Mechanistically, Ltv1 aids the recruitment of some RPs via direct protein-protein interactions, but surprisingly also delays the recruitment of other RPs. Delayed binding of key RPs also delays the acquisition of RNA structure that is stabilized by these proteins. Finally, our data also indicate direct roles for Ltv1 in chaperoning the folding of a key rRNA structural element, the three-helix junction j34-35-38. Thus, Ltv1 plays critical roles in organizing the order of both RP binding to rRNA and rRNA folding, thereby enabling efficient 40S subunit assembly.
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Affiliation(s)
- Ebba K. Blomqvist
- Department of Integrative Structural and Computational Biology, The Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, Florida 33458, United States of America
| | - Haina Huang
- Department of Integrative Structural and Computational Biology, The Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, Florida 33458, United States of America
- The Skaggs Graduate School of Chemical and Biological Sciences, The Scripps Research Institute, La Jolla, CA 92037
- Present Address: Arrakis Therapeutics, Waltham, MA 02451
| | - Katrin Karbstein
- Department of Integrative Structural and Computational Biology, The Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, Jupiter, Florida 33458, United States of America
- The Skaggs Graduate School of Chemical and Biological Sciences, The Scripps Research Institute, La Jolla, CA 92037
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Parker MD, Karbstein K. Quality control ensures fidelity in ribosome assembly and cellular health. J Cell Biol 2023; 222:e202209115. [PMID: 36790396 PMCID: PMC9960125 DOI: 10.1083/jcb.202209115] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 01/09/2023] [Accepted: 02/02/2023] [Indexed: 02/16/2023] Open
Abstract
The coordinated integration of ribosomal RNA and protein into two functional ribosomal subunits is safeguarded by quality control checkpoints that ensure ribosomes are correctly assembled and functional before they engage in translation. Quality control is critical in maintaining the integrity of ribosomes and necessary to support healthy cell growth and prevent diseases associated with mistakes in ribosome assembly. Its importance is demonstrated by the finding that bypassing quality control leads to misassembled, malfunctioning ribosomes with altered translation fidelity, which change gene expression and disrupt protein homeostasis. In this review, we outline our understanding of quality control within ribosome synthesis and how failure to enforce quality control contributes to human disease. We first provide a definition of quality control to guide our investigation, briefly present the main assembly steps, and then examine stages of assembly that test ribosome function, establish a pass-fail system to evaluate these functions, and contribute to altered ribosome performance when bypassed, and are thus considered "quality control."
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Affiliation(s)
- Melissa D. Parker
- The Skaggs Graduate School of Chemical and Biological Sciences, The Scripps Research Institute, La Jolla, CA, USA
- University of Florida—Scripps Biomedical Research, Jupiter, FL, USA
| | - Katrin Karbstein
- The Skaggs Graduate School of Chemical and Biological Sciences, The Scripps Research Institute, La Jolla, CA, USA
- University of Florida—Scripps Biomedical Research, Jupiter, FL, USA
- Howard Hughes Medical Institute Faculty Scholar, Howard Hughes Medical Institute, Chevy Chase, MD, USA
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Zhang Q, Lin R, Yang J, Zhao J, Li H, Liu K, Xue X, Zhao H, Han S, Zhao H. Transcriptome Analysis Reveals That C17 Mycosubtilin Antagonizes Verticillium dahliae by Interfering with Multiple Functional Pathways of Fungi. BIOLOGY 2023; 12:biology12040513. [PMID: 37106714 PMCID: PMC10136297 DOI: 10.3390/biology12040513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 03/20/2023] [Accepted: 03/23/2023] [Indexed: 03/31/2023]
Abstract
Verticillium wilt is a kind of soil-borne plant fungal disease caused by Verticillium dahliae (Vd). Vd 991 is a strong pathogen causing cotton Verticillium wilt. Previously, we isolated a compound from the secondary metabolites of Bacillus subtilis J15 (BS J15), which showed a significant control effect on cotton Verticillium wilt and was identified as C17 mycosubtilin. However, the specific fungistatic mechanism by which C17 mycosubtilin antagonizes Vd 991 is not clear. Here, we first showed that C17 mycosubtilin inhibits the growth of Vd 991 and affects germination of spores at the minimum inhibitory concentration (MIC). Morphological observation showed that C17 mycosubtilin treatment caused shrinking, sinking, and even damage to spores; the hyphae became twisted and rough, the surface was sunken, and the contents were unevenly distributed, resulting in thinning and damage to the cell membrane and cell wall and swelling of mitochondria of fungi. Flow cytometry analysis with ANNEXINV-FITC/PI staining showed that C17 mycosubtilin induces necrosis of Vd 991 cells in a time-dependent manner. Differential transcription analysis showed that C17 mycosubtilin at a semi-inhibitory concentration (IC50) treated Vd 991 for 2 and 6 h and inhibited fungal growth mainly by destroying synthesis of the fungal cell membrane and cell wall, inhibiting its DNA replication and transcriptional translation process, blocking its cell cycle, destroying fungal energy and substance metabolism, and disrupting the redox process of fungi. These results directly showed the mechanism by which C17 mycosubtilin antagonizes Vd 991, providing clues for the mechanism of action of lipopeptides and useful information for development of more effective antimicrobials.
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Abstract
Although differential transcription drives the development of multicellular organisms, the ultimate readout of a protein-coding gene is ribosome-dependent mRNA translation. Ribosomes were once thought of as uniform molecular machines, but emerging evidence indicates that the complexity and diversity of ribosome biogenesis and function should be given a fresh look in the context of development. This Review begins with a discussion of different developmental disorders that have been linked with perturbations in ribosome production and function. We then highlight recent studies that reveal how different cells and tissues exhibit variable levels of ribosome production and protein synthesis, and how changes in protein synthesis capacity can influence specific cell fate decisions. We finish by touching upon ribosome heterogeneity in stress responses and development. These discussions highlight the importance of considering both ribosome levels and functional specialization in the context of development and disease.
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Affiliation(s)
- Chunyang Ni
- Department of Molecular Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - Michael Buszczak
- Department of Molecular Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
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11
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Ni C, Buszczak M. The homeostatic regulation of ribosome biogenesis. Semin Cell Dev Biol 2023; 136:13-26. [PMID: 35440410 PMCID: PMC9569395 DOI: 10.1016/j.semcdb.2022.03.043] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 03/30/2022] [Accepted: 03/31/2022] [Indexed: 12/22/2022]
Abstract
The continued integrity of biological systems depends on a balance between interdependent elements at the molecular, cellular, and organismal levels. This is particularly true for the generation of ribosomes, which influence almost every aspect of cell and organismal biology. Ribosome biogenesis (RiBi) is an energetically demanding process that involves all three RNA polymerases, numerous RNA processing factors, chaperones, and the coordinated expression of 79-80 ribosomal proteins (r-proteins). Work over the last several decades has revealed that the dynamic regulation of ribosome production represents a major mechanism by which cells maintain homeostasis in response to changing environmental conditions and acute stress. More recent studies suggest that cells and tissues within multicellular organisms exhibit dramatically different levels of ribosome production and protein synthesis, marked by the differential expression of RiBi factors. Thus, distinct bottlenecks in the RiBi process, downstream of rRNA transcription, may exist within different cell populations of multicellular organisms during development and in adulthood. This review will focus on our current understanding of the mechanisms that link the complex molecular process of ribosome biogenesis with cellular and organismal physiology. We will discuss diverse topics including how different steps in the RiBi process are coordinated with one another, how MYC and mTOR impact RiBi, and how RiBi levels change between stem cells and their differentiated progeny. In turn, we will also review how regulated changes in ribosome production itself can feedback to influence cell fate and function.
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Affiliation(s)
- Chunyang Ni
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9148, USA
| | - Michael Buszczak
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9148, USA.
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12
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Chen H, Jin J, Hu S, Shen L, Zhang P, Li Z, Fang Z, Liu H. Metabolomics and proteomics reveal the toxicological mechanisms of florfenicol stress on wheat (Triticum aestivum L.) seedlings. JOURNAL OF HAZARDOUS MATERIALS 2023; 443:130264. [PMID: 36327828 DOI: 10.1016/j.jhazmat.2022.130264] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Revised: 10/16/2022] [Accepted: 10/24/2022] [Indexed: 06/16/2023]
Abstract
Although the ecological impacts of antibiotics have received attention worldwide, research on the toxicity of florfenicol is still limited. We conducted a metabolomic and proteomic study on wheat (Triticum aestivum L.) seedlings to reveal the toxicological mechanism of florfenicol. The growth of the wheat seedlings was found to be inhibited by florfenicol. Antioxidant enzyme activities (superoxide dismutase, peroxidase and catalase), malondialdehyde content and membrane permeability increased with increasing florfenicol concentration. The contents of chlorophyll and chlorophyll synthesis precursor substances (Proto IX, Mg-proto IX and Pchlide), photosynthetic and respiration rates, and chlorophyll fluorescence parameters decreased, indicating that photosynthesis was inhibited. The ultrastructure of chloroplasts was destroyed, as evidenced by the blurred membrane surface, irregular grana arrangement, irregular thylakoid lamella structure, and increased plastoglobuli number. Proteome analysis revealed that up-regulated proteins were highly involved in protein refolding, translation, oxidation-reduction, tricarboxylic acid cycle (TCA cycle), reactive oxygen species metabolic process, cellular oxidant detoxification, and response to oxidative stress. The down-regulated proteins were mainly enriched in photosynthesis-related pathways. In the metabolome analysis, the content of most of the metabolites in wheat leaves, such as carbohydrates and amino acids increased significantly (p < 0.05). Combined pathway analysis showed that florfenicol stress stimulated the TCA cycle pathway and downregulated the photosynthesis pathway.
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Affiliation(s)
- Hanmei Chen
- School of Environmental Science and Engineering, Instrumental analysis center, Zhejiang Gongshang University, Hangzhou 310018, PR China
| | - Jiaojun Jin
- School of Environmental Science and Engineering, Instrumental analysis center, Zhejiang Gongshang University, Hangzhou 310018, PR China
| | - Shuhao Hu
- School of Environmental Science and Engineering, Instrumental analysis center, Zhejiang Gongshang University, Hangzhou 310018, PR China
| | - Luoqin Shen
- School of Environmental Science and Engineering, Instrumental analysis center, Zhejiang Gongshang University, Hangzhou 310018, PR China
| | - Ping Zhang
- School of Environmental Science and Engineering, Instrumental analysis center, Zhejiang Gongshang University, Hangzhou 310018, PR China
| | - Zhiheng Li
- School of Environmental Science and Engineering, Instrumental analysis center, Zhejiang Gongshang University, Hangzhou 310018, PR China
| | - Zhiguo Fang
- School of Environmental Science and Engineering, Instrumental analysis center, Zhejiang Gongshang University, Hangzhou 310018, PR China
| | - Huijun Liu
- School of Environmental Science and Engineering, Instrumental analysis center, Zhejiang Gongshang University, Hangzhou 310018, PR China.
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13
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Xing C, Chen S, Wang Y, Pan Z, Zou Y, Sun S, Ren Z, Zhang Y. Glyphosate exposure deteriorates oocyte meiotic maturation via induction of organelle dysfunctions in pigs. J Anim Sci Biotechnol 2022; 13:80. [PMID: 35799248 PMCID: PMC9264682 DOI: 10.1186/s40104-022-00732-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 05/12/2022] [Indexed: 12/13/2022] Open
Abstract
Background Recently, defects in mammalian oocytes maturation induced by environmental pollution results in the decreasing animal reproduction. Animal exposed to glyphosate is largely unavoidable because glyphosate is one of the most widely used herbicide worldwide due to its high-efficiency and broad-spectrum effects, which causes glyphosate an environmental contaminant found in soil, water and food. During the last few years, the growing and wider use of glyphosate has raised great concerns about its effects of reproductive toxicity. In this study, using porcine models, we investigated effects of glyphosate on organelle functions during oocyte meiosis. Results The results showed glyphosate exposure disrupted porcine oocyte maturation. Expression levels of cumulus expansion-related genes were interfered, further indicating the meiotic defects. The damaging effects were mediated by destruction of mitochondrial distribution and functions, which induced ROS accumulation and oxidative stress, also indicated by the decreased mRNA expression of related antioxidant enzyme genes. We also found an interference of endoplasmic reticulum (ER) distribution, disturbance of Ca2+ homeostasis, as well as fluctuation of ER stress, showing with the reduced ER stress-related mRNA or protein expression, which could indicate the dysfunction of ER for protein processing and signal transduction in glyphosate-exposed oocytes. Moreover, glyphosate exposure induced the disruption of lysosome function for autophagy, showing with the decrease of LAMP2 expression and autophagy-related genes mRNA expression. Additionally, our data showed the distribution of Golgi apparatus and the functions of ribosome were disturbed after glyphosate exposure, which might affect protein synthesis and transport. Conclusions Collectively, our study showed that exposed to glyphosate could affect animal reproduction by compromising the quality of oocytes through its wide toxic effects on organelle functions.
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Affiliation(s)
- Chunhua Xing
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China
| | - Shun Chen
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yue Wang
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China
| | - Zhennan Pan
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yuanjing Zou
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China
| | - Shaochen Sun
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China
| | - Zili Ren
- College of Animal Science, Tibet Agricultural and Animal Husbandry University, Linzhi, 860000, Tibet, China
| | - Yu Zhang
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China.
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14
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Han JH, Ryan G, Guy A, Liu L, Quinodoz M, Helbling I, Lai-Cheong JE, Barwell J, Folcher M, McGrath JA, Moss C, Rivolta C. Mutations in the ribosome biogenesis factor gene LTV1 are linked to LIPHAK syndrome, a novel poikiloderma-like disorder. Hum Mol Genet 2022; 31:1970-1978. [PMID: 34999892 PMCID: PMC9239743 DOI: 10.1093/hmg/ddab368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 11/18/2021] [Accepted: 12/13/2021] [Indexed: 11/12/2022] Open
Abstract
In the framework of the UK 100 000 Genomes Project, we investigated the genetic origin of a previously undescribed recessive dermatological condition, which we named LIPHAK (LTV1-associated Inflammatory Poikiloderma with Hair abnormalities and Acral Keratoses), in four affected individuals from two UK families of Pakistani and Indian origins, respectively. Our analysis showed that only one gene, LTV1, carried rare biallelic variants that were shared in all affected individuals, and specifically they bore the NM_032860.5:c.503A > G, p.(Asn168Ser) change, found homozygously in all of them. In addition, high-resolution homozygosity mapping revealed the presence of a small 652-kb stretch on chromosome 6, encompassing LTV1, that was haploidentical and common to all affected individuals. The c.503A > G variant was predicted by in silico tools to affect the correct splicing of LTV1's exon 5. Minigene-driven splicing assays in HEK293T cells and in a skin sample from one of the patients confirmed that this variant was indeed responsible for the creation of a new donor splice site, resulting in aberrant splicing and in a premature termination codon in exon 6 of this gene. LTV1 encodes one of the ribosome biogenesis factors that promote the assembly of the small (40S) ribosomal subunit. In yeast, defects in LTV1 alter the export of nascent ribosomal subunits to the cytoplasm; however, the role of this gene in human pathology is unknown to date. Our data suggest that LIPHAK could be a previously unrecognized ribosomopathy.
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Affiliation(s)
- Ji Hoon Han
- Institute of Molecular and Clinical Ophthalmology Basel (IOB), 4031 Basel, Switzerland
- Department of Ophthalmology, University of Basel, 4031 Basel, Switzerland
| | - Gavin Ryan
- West Midlands Regional Genetics Laboratory, Central and South Genomic Laboratory Hub, Birmingham B15 2TG, UK
| | - Alyson Guy
- Viapath, St Thomas' Hospital, London SE1 7EH, UK
| | - Lu Liu
- Viapath, St Thomas' Hospital, London SE1 7EH, UK
| | - Mathieu Quinodoz
- Institute of Molecular and Clinical Ophthalmology Basel (IOB), 4031 Basel, Switzerland
- Department of Ophthalmology, University of Basel, 4031 Basel, Switzerland
- Department of Genetics and Genome Biology, University of Leicester, Leicester LE1 7RH, UK
| | - Ingrid Helbling
- Department of Dermatology, University Hospitals of Leicester NHS Trust, Leicester LE1 5WW, UK
| | | | | | - Julian Barwell
- Department of Genetics and Genome Biology, University of Leicester, Leicester LE1 7RH, UK
- Department of Clinical Genetics, University Hospitals of Leicester NHS Trust, Leicester LE1 5WW, UK
| | - Marc Folcher
- Institute of Molecular and Clinical Ophthalmology Basel (IOB), 4031 Basel, Switzerland
- Department of Ophthalmology, University of Basel, 4031 Basel, Switzerland
| | - John A McGrath
- NIHR Biomedical Research Centre, Guy's and St Thomas' NHS Foundation Trust and King's College London, London SE1 9RT, UK
- St John's Institute of Dermatology, King's College London (Guy's campus), London SE1 9RT, UK
| | - Celia Moss
- Department of Paediatric Dermatology, Birmingham Women’s and Children’s Hospital NHS FT, Birmingham B4 6NH, UK
- College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Carlo Rivolta
- Institute of Molecular and Clinical Ophthalmology Basel (IOB), 4031 Basel, Switzerland
- Department of Ophthalmology, University of Basel, 4031 Basel, Switzerland
- Department of Genetics and Genome Biology, University of Leicester, Leicester LE1 7RH, UK
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15
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Wing CE, Fung HYJ, Chook YM. Karyopherin-mediated nucleocytoplasmic transport. Nat Rev Mol Cell Biol 2022; 23:307-328. [PMID: 35058649 PMCID: PMC10101760 DOI: 10.1038/s41580-021-00446-7] [Citation(s) in RCA: 117] [Impact Index Per Article: 58.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/09/2021] [Indexed: 12/25/2022]
Abstract
Efficient and regulated nucleocytoplasmic trafficking of macromolecules to the correct subcellular compartment is critical for proper functions of the eukaryotic cell. The majority of the macromolecular traffic across the nuclear pores is mediated by the Karyopherin-β (or Kap) family of nuclear transport receptors. Work over more than two decades has shed considerable light on how the different Kap family members bring their respective cargoes into the nucleus or the cytoplasm in efficient and highly regulated manners. In this Review, we overview the main features and established functions of Kap family members, describe how Kaps recognize their cargoes and discuss the different ways in which these Kap-cargo interactions can be regulated, highlighting new findings and open questions. We also describe current knowledge of the import and export of the components of three large gene expression machines - the core replisome, RNA polymerase II and the ribosome - pointing out the questions that persist about how such large macromolecular complexes are trafficked to serve their function in a designated subcellular location.
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16
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Mitterer V, Pertschy B. RNA folding and functions of RNA helicases in ribosome biogenesis. RNA Biol 2022; 19:781-810. [PMID: 35678541 PMCID: PMC9196750 DOI: 10.1080/15476286.2022.2079890] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Accepted: 05/16/2022] [Indexed: 11/13/2022] Open
Abstract
Eukaryotic ribosome biogenesis involves the synthesis of ribosomal RNA (rRNA) and its stepwise folding into the unique structure present in mature ribosomes. rRNA folding starts already co-transcriptionally in the nucleolus and continues when pre-ribosomal particles further maturate in the nucleolus and upon their transit to the nucleoplasm and cytoplasm. While the approximate order of folding of rRNA subdomains is known, especially from cryo-EM structures of pre-ribosomal particles, the actual mechanisms of rRNA folding are less well understood. Both small nucleolar RNAs (snoRNAs) and proteins have been implicated in rRNA folding. snoRNAs hybridize to precursor rRNAs (pre-rRNAs) and thereby prevent premature folding of the respective rRNA elements. Ribosomal proteins (r-proteins) and ribosome assembly factors might have a similar function by binding to rRNA elements and preventing their premature folding. Besides that, a small group of ribosome assembly factors are thought to play a more active role in rRNA folding. In particular, multiple RNA helicases participate in individual ribosome assembly steps, where they are believed to coordinate RNA folding/unfolding events or the release of proteins from the rRNA. In this review, we summarize the current knowledge on mechanisms of RNA folding and on the specific function of the individual RNA helicases involved. As the yeast Saccharomyces cerevisiae is the organism in which ribosome biogenesis and the role of RNA helicases in this process is best studied, we focused our review on insights from this model organism, but also make comparisons to other organisms where applicable.
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Affiliation(s)
- Valentin Mitterer
- Biochemistry Center, Heidelberg University, Im Neuenheimer Feld 328, Heidelberg, Germany
- BioTechMed-Graz, Graz, Austria
| | - Brigitte Pertschy
- BioTechMed-Graz, Graz, Austria
- Institute of Molecular Biosciences, University of Graz, Humboldtstrasse 50, Graz, Austria
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17
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Rössler I, Weigl S, Fernández-Fernández J, Martín-Villanueva S, Strauss D, Hurt E, de la Cruz J, Pertschy B. The C-terminal tail of ribosomal protein Rps15 is engaged in cytoplasmic pre-40S maturation. RNA Biol 2021; 19:560-574. [PMID: 35438042 PMCID: PMC9037480 DOI: 10.1080/15476286.2022.2064073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 04/04/2022] [Indexed: 11/22/2022] Open
Abstract
The small ribosomal subunit protein Rps15/uS19 is involved in early nucleolar ribosome biogenesis and subsequent nuclear export of pre-40S particles to the cytoplasm. In addition, the C-terminal tail of Rps15 was suggested to play a role in mature ribosomes, namely during translation elongation. Here, we show that Rps15 not only functions in nucleolar ribosome assembly but also in cytoplasmic pre-40S maturation, which is indicated by a strong genetic interaction between Rps15 and the 40S assembly factor Ltv1. Specifically, mutations either in the globular or C-terminal domain of Rps15 when combined with the non-essential ltv1 null allele are lethal or display a strong growth defect. However, not only rps15 ltv1 double mutants but also single rps15 C-terminal deletion mutants exhibit an accumulation of the 20S pre-rRNA in the cytoplasm, indicative of a cytoplasmic pre-40S maturation defect. Since in pre-40S particles, the C-terminal tail of Rps15 is positioned between assembly factors Rio2 and Tsr1, we further tested whether Tsr1 is genetically linked to Rps15, which indeed could be demonstrated. Thus, the integrity of the Rps15 C-terminal tail plays an important role during late pre-40S maturation, perhaps in a quality control step to ensure that only 40S ribosomal subunits with functional Rps15 C-terminal tail can efficiently enter translation. As mutations in the C-terminal tail of human RPS15 have been observed in connection with chronic lymphocytic leukaemia, it is possible that apart from defects in translation, an impaired late pre-40S maturation step in the cytoplasm could also be a reason for this disease.
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Affiliation(s)
- Ingrid Rössler
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
- BioTechMed-Graz, Graz, Austria
| | - Sarah Weigl
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - José Fernández-Fernández
- Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Seville, Spain
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla, Seville, Spain
| | - Sara Martín-Villanueva
- Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Seville, Spain
| | - Daniela Strauss
- Biochemistry Center BZH, Heidelberg University, Heidelberg, Germany
| | - Ed Hurt
- Biochemistry Center BZH, Heidelberg University, Heidelberg, Germany
| | - Jesús de la Cruz
- Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Seville, Spain
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla, Seville, Spain
| | - Brigitte Pertschy
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
- BioTechMed-Graz, Graz, Austria
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18
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Cerezo EL, Houles T, Lié O, Sarthou MK, Audoynaud C, Lavoie G, Halladjian M, Cantaloube S, Froment C, Burlet-Schiltz O, Henry Y, Roux PP, Henras AK, Romeo Y. RIOK2 phosphorylation by RSK promotes synthesis of the human small ribosomal subunit. PLoS Genet 2021; 17:e1009583. [PMID: 34125833 PMCID: PMC8224940 DOI: 10.1371/journal.pgen.1009583] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 06/24/2021] [Accepted: 05/05/2021] [Indexed: 11/18/2022] Open
Abstract
Ribosome biogenesis lies at the nexus of various signaling pathways coordinating protein synthesis with cell growth and proliferation. This process is regulated by well-described transcriptional mechanisms, but a growing body of evidence indicates that other levels of regulation exist. Here we show that the Ras/mitogen-activated protein kinase (MAPK) pathway stimulates post-transcriptional stages of human ribosome synthesis. We identify RIOK2, a pre-40S particle assembly factor, as a new target of the MAPK-activated kinase RSK. RIOK2 phosphorylation by RSK stimulates cytoplasmic maturation of late pre-40S particles, which is required for optimal protein synthesis and cell proliferation. RIOK2 phosphorylation facilitates its release from pre-40S particles and its nuclear re-import, prior to completion of small ribosomal subunits. Our results bring a detailed mechanistic link between the Ras/MAPK pathway and the maturation of human pre-40S particles, which opens a hitherto poorly explored area of ribosome biogenesis.
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Affiliation(s)
- Emilie L. Cerezo
- Molecular, Cellular and Developmental biology department (MCD), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Thibault Houles
- Institute for Research in Immunology and Cancer, Université de Montréal, Montreal, Québec, Canada
| | - Oriane Lié
- Molecular, Cellular and Developmental biology department (MCD), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Marie-Kerguelen Sarthou
- Molecular, Cellular and Developmental biology department (MCD), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Charlotte Audoynaud
- Molecular, Cellular and Developmental biology department (MCD), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Geneviève Lavoie
- Institute for Research in Immunology and Cancer, Université de Montréal, Montreal, Québec, Canada
| | - Maral Halladjian
- Molecular, Cellular and Developmental biology department (MCD), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Sylvain Cantaloube
- Molecular, Cellular and Developmental biology department (MCD), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Carine Froment
- Institut de Pharmacologie et Biologie Structurale (IPBS), Université de Toulouse, UPS, CNRS, Toulouse, France
| | - Odile Burlet-Schiltz
- Institut de Pharmacologie et Biologie Structurale (IPBS), Université de Toulouse, UPS, CNRS, Toulouse, France
| | - Yves Henry
- Molecular, Cellular and Developmental biology department (MCD), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Philippe P. Roux
- Institute for Research in Immunology and Cancer, Université de Montréal, Montreal, Québec, Canada
- Department of Pathology and Cell Biology, Faculty of Medicine, Université de Montréal, Montreal, Québec, Canada
| | - Anthony K. Henras
- Molecular, Cellular and Developmental biology department (MCD), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Yves Romeo
- Molecular, Cellular and Developmental biology department (MCD), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
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19
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Huang H, Ghalei H, Karbstein K. Quality control of 40S ribosome head assembly ensures scanning competence. J Cell Biol 2021; 219:152152. [PMID: 33007085 PMCID: PMC7534925 DOI: 10.1083/jcb.202004161] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 06/25/2020] [Accepted: 08/13/2020] [Indexed: 11/22/2022] Open
Abstract
During translation initiation, 40S ribosomes scan the mRNA until they encounter the start codon, where conformational changes produce a translation-competent 80S complex. Destabilizing the scanning complex results in misinitiation at non-AUG codons, demonstrating its importance for fidelity. Here, we use a combination of biochemical and genetic analyses to demonstrate that the ability of the nascent subunit to adopt the scanning complex is tested during assembly via structural mimicry. Specifically, formation of the 80S-like assembly intermediate, which structurally resembles scanning complexes, requires the correct folding of two rRNA elements in the subunit head and the proper positioning of the universally conserved head proteins Rps3, Rps15, Rps20, and Rps29. rRNA misfolding impairs the formation of 80S-like ribosomes, and bypass of individual checkpoints using cancer-associated mutations produces ribosomes defective in accurate start-site selection. Thus, the formation of 80S-like assembly intermediates is a quality control step that ensures scanning competence of the nascent subunit.
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Affiliation(s)
- Haina Huang
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, Jupiter, FL
| | - Homa Ghalei
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, Jupiter, FL
| | - Katrin Karbstein
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, Jupiter, FL.,Howard Hughes Medical Institute, Chevy Chase, MD
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20
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Rai J, Parker MD, Huang H, Choy S, Ghalei H, Johnson MC, Karbstein K, Stroupe ME. An open interface in the pre-80S ribosome coordinated by ribosome assembly factors Tsr1 and Dim1 enables temporal regulation of Fap7. RNA (NEW YORK, N.Y.) 2021; 27:221-233. [PMID: 33219089 PMCID: PMC7812869 DOI: 10.1261/rna.077610.120] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Accepted: 11/17/2020] [Indexed: 06/11/2023]
Abstract
During their maturation, nascent 40S subunits enter a translation-like quality control cycle, where they are joined by mature 60S subunits to form 80S-like ribosomes. While these assembly intermediates are essential for maturation and quality control, how they form, and how their structure promotes quality control, remains unknown. To address these questions, we determined the structure of an 80S-like ribosome assembly intermediate to an overall resolution of 3.4 Å. The structure, validated by biochemical data, resolves a large body of previously paradoxical data and illustrates how assembly and translation factors cooperate to promote the formation of an interface that lacks many mature subunit contacts but is stabilized by the universally conserved methyltransferase Dim1. We also show how Tsr1 enables this interface by blocking the canonical binding of eIF5B to 40S subunits, while maintaining its binding to 60S. The structure also shows how this interface leads to unfolding of the platform, which allows for temporal regulation of the ATPase Fap7, thus linking 40S maturation to quality control during ribosome assembly.
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MESH Headings
- Adenylate Kinase/chemistry
- Adenylate Kinase/genetics
- Adenylate Kinase/metabolism
- Binding Sites
- Gene Expression Regulation, Fungal
- Methyltransferases/chemistry
- Methyltransferases/genetics
- Methyltransferases/metabolism
- Models, Molecular
- Nuclear Proteins/chemistry
- Nuclear Proteins/genetics
- Nuclear Proteins/metabolism
- Nucleoside-Triphosphatase/chemistry
- Nucleoside-Triphosphatase/genetics
- Nucleoside-Triphosphatase/metabolism
- Organelle Biogenesis
- Protein Binding
- Protein Biosynthesis
- Protein Conformation, alpha-Helical
- Protein Conformation, beta-Strand
- Protein Interaction Domains and Motifs
- Ribosomal Proteins/chemistry
- Ribosomal Proteins/genetics
- Ribosomal Proteins/metabolism
- Ribosome Subunits, Large, Eukaryotic/genetics
- Ribosome Subunits, Large, Eukaryotic/metabolism
- Ribosome Subunits, Large, Eukaryotic/ultrastructure
- Ribosome Subunits, Small, Eukaryotic/genetics
- Ribosome Subunits, Small, Eukaryotic/metabolism
- Ribosome Subunits, Small, Eukaryotic/ultrastructure
- Saccharomyces cerevisiae/genetics
- Saccharomyces cerevisiae/metabolism
- Saccharomyces cerevisiae Proteins/chemistry
- Saccharomyces cerevisiae Proteins/genetics
- Saccharomyces cerevisiae Proteins/metabolism
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Affiliation(s)
- Jay Rai
- Department of Biological Science and the Institute of Molecular Biophysics, Florida State University, Tallahassee, Florida 32306, USA
| | - Melissa D Parker
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, Jupiter, Florida 33458, USA
| | - Haina Huang
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, Jupiter, Florida 33458, USA
| | - Stefan Choy
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, Jupiter, Florida 33458, USA
| | - Homa Ghalei
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, Jupiter, Florida 33458, USA
| | - Matthew C Johnson
- Department of Biological Science and the Institute of Molecular Biophysics, Florida State University, Tallahassee, Florida 32306, USA
| | - Katrin Karbstein
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, Jupiter, Florida 33458, USA
- HHMI Faculty Scholar, Howard Hughes Medical Institute, Chevy Chase, Maryland 20815, USA
| | - M Elizabeth Stroupe
- Department of Biological Science and the Institute of Molecular Biophysics, Florida State University, Tallahassee, Florida 32306, USA
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21
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Interactions between tumor-derived proteins and Toll-like receptors. Exp Mol Med 2020; 52:1926-1935. [PMID: 33299138 PMCID: PMC8080774 DOI: 10.1038/s12276-020-00540-4] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 10/20/2020] [Accepted: 11/02/2020] [Indexed: 12/23/2022] Open
Abstract
Damage-associated molecular patterns (DAMPs) are danger signals (or alarmins) alerting immune cells through pattern recognition receptors (PRRs) to begin defense activity. Moreover, DAMPs are host biomolecules that can initiate a noninflammatory response to infection, and pathogen-associated molecular pattern (PAMPs) perpetuate the inflammatory response to infection. Many DAMPs are proteins that have defined intracellular functions and are released from dying cells after tissue injury or chemo-/radiotherapy. In the tumor microenvironment, DAMPs can be ligands for Toll-like receptors (TLRs) expressed on immune cells and induce cytokine production and T-cell activation. Moreover, DAMPs released from tumor cells can directly activate tumor-expressed TLRs that induce chemoresistance, migration, invasion, and metastasis. Furthermore, DAMP-induced chronic inflammation in the tumor microenvironment causes an increase in immunosuppressive populations, such as M2 macrophages, myeloid-derived suppressor cells (MDSCs), and regulatory T cells (Tregs). Therefore, regulation of DAMP proteins can reduce excessive inflammation to create an immunogenic tumor microenvironment. Here, we review tumor-derived DAMP proteins as ligands of TLRs and discuss their association with immune cells, tumors, and the composition of the tumor microenvironment. Tumor cells killed by radiotherapy or chemotherapy release signaling molecules that stimulate both immune response and tumor aggressiveness; regulating these molecules could improve treatment efficacy. Tae Heung Kang, Yeong-Min Park, and co-workers at Konkuk University, Seoul, South Korea, have reviewed the role of damage-associated molecular patterns (DAMPs) in immunity and cancer. These signaling molecules act as danger signals, activating immune cells by binding to specific receptors. However, tumor cells have the same receptors, and DAMPs binding triggers chemoresistance and increases invasiveness. The researchers report that although DAMPs can trigger a helpful immune response, they can also cause chronic inflammation, which in turn promotes an immune suppression response, allowing tumors to escape immune detection. Improving our understanding of the functions of different DAMPs could improve our ability to boost the immune response and decrease tumor aggressiveness.
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22
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Graifer D, Karpova G. Ribosomal protein uS3 in cell biology and human disease: Latest insights and prospects. Bioessays 2020; 42:e2000124. [PMID: 33179285 DOI: 10.1002/bies.202000124] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 09/14/2020] [Indexed: 12/20/2022]
Abstract
The conserved ribosomal protein uS3 in eukaryotes has long been known as one of the essential components of the small (40S) ribosomal subunit, which is involved in the structure of the 40S mRNA entry pore, ensuring the functioning of the 40S subunit during translation initiation. Besides, uS3, being outside the ribosome, is engaged in various cellular processes related to DNA repair, NF-kB signaling pathway and regulation of apoptosis. This review is devoted to recent data opening new horizons in understanding the roles of uS3 in such processes as the assembly and maturation of 40S subunits, ensuring proper structure of 48S pre-initiation complexes, regulation of initiation and ribosome-based RNA quality control pathways. Besides, we summarize novel results on the participation of the protein in processes beyond translation and consider biomedical implications of previously known and recently found extra-ribosomal functions of uS3, primarily, in oncogenesis.
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Affiliation(s)
- Dmitri Graifer
- Institute of Chemical Biology and Fundamental Medicine SB RAS, Novosibirsk, Russia
| | - Galina Karpova
- Institute of Chemical Biology and Fundamental Medicine SB RAS, Novosibirsk, Russia
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23
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Babaylova ES, Kolobova AV, Gopanenko AV, Tupikin AE, Kabilov MR, Malygin AA, Karpova GG. The human ribosomal protein eL29 binds in vivo to the cognate mRNA by interacting with its coding sequence, as revealed from in-cell cross-linking data. Biochimie 2020; 177:68-77. [DOI: 10.1016/j.biochi.2020.07.019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 07/31/2020] [Accepted: 07/31/2020] [Indexed: 01/21/2023]
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24
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Martín-Villanueva S, Fernández-Fernández J, Rodríguez-Galán O, Fernández-Boraita J, Villalobo E, de La Cruz J. Role of the 40S beak ribosomal protein eS12 in ribosome biogenesis and function in Saccharomyces cerevisiae. RNA Biol 2020; 17:1261-1276. [PMID: 32408794 DOI: 10.1080/15476286.2020.1767951] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
Abstract
In eukaryotes, the beak structure of 40S subunits is formed by the protrusion of the 18S rRNA helix 33 and three ribosomal proteins: eS10, eS12 and eS31. The exact role of these proteins in ribosome biogenesis is not well understood. While eS10 is an essential protein encoded by two paralogous genes in Saccharomyces cerevisiae, eS12 and eS31 are not essential proteins encoded by the single-copy genes RPS12 and UBI3, respectively. Here, we have analysed the contribution of yeast eS12 to ribosome biogenesis and compared it with that of eS31. Polysome analysis reveals that deletion of either RPS12 or UBI3 results in equivalent 40S deficits. Analysis of pre-rRNA processing indicates that eS12, akin to eS31, is required for efficient processing of 20S pre-rRNA to mature 18S rRNA. Moreover, we show that the 20S pre-rRNA accumulates within cytoplasmic pre-40S particles, as deduced from FISH experiments and the lack of nuclear retention of 40S subunit reporter proteins, in rps12∆ and ubi3∆ cells. However, these particles containing 20S pre-rRNA are not efficiently incorporated into polyribosomes. We also provide evidence for a genetic interaction between eS12 or eS31 and the late-acting 40S assembly factors Enp1 and Ltv1, which appears not to be linked to the dynamics of their association with or release from pre-40S particles in the absence of either eS12 or eS31. Finally, we show that eS12- and eS31-deficient ribosomes exhibit increased levels of translational misreading. Altogether, our data highlight distinct important roles of the beak region during ribosome assembly and function.
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Affiliation(s)
- Sara Martín-Villanueva
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla , Seville, Spain.,Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla , Seville, Spain
| | - José Fernández-Fernández
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla , Seville, Spain.,Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla , Seville, Spain
| | - Olga Rodríguez-Galán
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla , Seville, Spain.,Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla , Seville, Spain
| | - Julia Fernández-Boraita
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla , Seville, Spain.,Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla , Seville, Spain
| | - Eduardo Villalobo
- Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla , Seville, Spain.,Departamento de Microbiología, Facultad de Biología, Universidad de Sevilla , Seville, Spain
| | - Jesús de La Cruz
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla , Seville, Spain.,Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla , Seville, Spain
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25
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Shayan R, Rinaldi D, Larburu N, Plassart L, Balor S, Bouyssié D, Lebaron S, Marcoux J, Gleizes PE, Plisson-Chastang C. Good Vibrations: Structural Remodeling of Maturing Yeast Pre-40S Ribosomal Particles Followed by Cryo-Electron Microscopy. Molecules 2020; 25:molecules25051125. [PMID: 32138239 PMCID: PMC7179242 DOI: 10.3390/molecules25051125] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Revised: 02/24/2020] [Accepted: 02/27/2020] [Indexed: 12/03/2022] Open
Abstract
Assembly of eukaryotic ribosomal subunits is a very complex and sequential process that starts in the nucleolus and finishes in the cytoplasm with the formation of functional ribosomes. Over the past few years, characterization of the many molecular events underlying eukaryotic ribosome biogenesis has been drastically improved by the “resolution revolution” of cryo-electron microscopy (cryo-EM). However, if very early maturation events have been well characterized for both yeast ribosomal subunits, little is known regarding the final maturation steps occurring to the small (40S) ribosomal subunit. To try to bridge this gap, we have used proteomics together with cryo-EM and single particle analysis to characterize yeast pre-40S particles containing the ribosome biogenesis factor Tsr1. Our analyses lead us to refine the timing of the early pre-40S particle maturation steps. Furthermore, we suggest that after an early and structurally stable stage, the beak and platform domains of pre-40S particles enter a “vibrating” or “wriggling” stage, that might be involved in the final maturation of 18S rRNA as well as the fitting of late ribosomal proteins into their mature position.
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Affiliation(s)
- Ramtin Shayan
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative, Université de Toulouse, CNRS, UPS, 118 route de Narbonne, 31062 Toulouse CEDEX, France; (R.S.); (D.R.); (N.L.); (L.P.); (S.B.); (S.L.)
| | - Dana Rinaldi
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative, Université de Toulouse, CNRS, UPS, 118 route de Narbonne, 31062 Toulouse CEDEX, France; (R.S.); (D.R.); (N.L.); (L.P.); (S.B.); (S.L.)
| | - Natacha Larburu
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative, Université de Toulouse, CNRS, UPS, 118 route de Narbonne, 31062 Toulouse CEDEX, France; (R.S.); (D.R.); (N.L.); (L.P.); (S.B.); (S.L.)
| | - Laura Plassart
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative, Université de Toulouse, CNRS, UPS, 118 route de Narbonne, 31062 Toulouse CEDEX, France; (R.S.); (D.R.); (N.L.); (L.P.); (S.B.); (S.L.)
| | - Stéphanie Balor
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative, Université de Toulouse, CNRS, UPS, 118 route de Narbonne, 31062 Toulouse CEDEX, France; (R.S.); (D.R.); (N.L.); (L.P.); (S.B.); (S.L.)
| | - David Bouyssié
- Institut de Pharmacologie et Biologie Structurale, Université de Toulouse, CNRS, UPS, 205 route de Narbonne, 31062 Toulouse CEDEX, France;
| | - Simon Lebaron
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative, Université de Toulouse, CNRS, UPS, 118 route de Narbonne, 31062 Toulouse CEDEX, France; (R.S.); (D.R.); (N.L.); (L.P.); (S.B.); (S.L.)
| | - Julien Marcoux
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative, Université de Toulouse, CNRS, UPS, 118 route de Narbonne, 31062 Toulouse CEDEX, France; (R.S.); (D.R.); (N.L.); (L.P.); (S.B.); (S.L.)
- Correspondence: (J.M.); (P.-E.G.); (C.P.-C.)
| | - Pierre-Emmanuel Gleizes
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative, Université de Toulouse, CNRS, UPS, 118 route de Narbonne, 31062 Toulouse CEDEX, France; (R.S.); (D.R.); (N.L.); (L.P.); (S.B.); (S.L.)
- Correspondence: (J.M.); (P.-E.G.); (C.P.-C.)
| | - Célia Plisson-Chastang
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative, Université de Toulouse, CNRS, UPS, 118 route de Narbonne, 31062 Toulouse CEDEX, France; (R.S.); (D.R.); (N.L.); (L.P.); (S.B.); (S.L.)
- Correspondence: (J.M.); (P.-E.G.); (C.P.-C.)
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26
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Maurice F, Pérébaskine N, Thore S, Fribourg S. In vitro dimerization of human RIO2 kinase. RNA Biol 2019; 16:1633-1642. [PMID: 31390939 DOI: 10.1080/15476286.2019.1653679] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
RIO proteins form a conserved family of atypical protein kinases. RIO2 is a serine/threonine protein kinase/ATPase involved in pre-40S ribosomal maturation. Current crystal structures of archaeal and fungal Rio2 proteins report a monomeric form of the protein. Here, we describe three atomic structures of the human RIO2 kinase showing that it forms a homodimer in vitro. Upon self-association, each protomer ATP-binding pocket is partially remodelled and found in an apostate. The homodimerization is mediated by key residues previously shown to be responsible for ATP binding and catalysis. This unusual in vitro protein kinase dimer reveals an intricate mechanism where identical residues are involved in substrate binding and oligomeric state formation. We speculate that such an oligomeric state might be formed also in vivo and might function in maintaining the protein in an inactive state and could be employed during import.
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Affiliation(s)
| | | | - Stéphane Thore
- INSERM U1212, UMR CNRS 5320, Université de Bordeaux , Bordeaux , France
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27
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Rössler I, Embacher J, Pillet B, Murat G, Liesinger L, Hafner J, Unterluggauer JJ, Birner-Gruenberger R, Kressler D, Pertschy B. Tsr4 and Nap1, two novel members of the ribosomal protein chaperOME. Nucleic Acids Res 2019; 47:6984-7002. [PMID: 31062022 PMCID: PMC6648895 DOI: 10.1093/nar/gkz317] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 04/15/2019] [Accepted: 04/19/2019] [Indexed: 12/12/2022] Open
Abstract
Dedicated chaperones protect newly synthesized ribosomal proteins (r-proteins) from aggregation and accompany them on their way to assembly into nascent ribosomes. Currently, only nine of the ∼80 eukaryotic r-proteins are known to be guarded by such chaperones. In search of new dedicated r-protein chaperones, we performed a tandem-affinity purification based screen and looked for factors co-enriched with individual small subunit r-proteins. We report the identification of Nap1 and Tsr4 as direct binding partners of Rps6 and Rps2, respectively. Both factors promote the solubility of their r-protein clients in vitro. While Tsr4 is specific for Rps2, Nap1 has several interaction partners including Rps6 and two other r-proteins. Tsr4 binds co-translationally to the essential, eukaryote-specific N-terminal extension of Rps2, whereas Nap1 interacts with a large, mostly eukaryote-specific binding surface of Rps6. Mutation of the essential Tsr4 and deletion of the non-essential Nap1 both enhance the 40S synthesis defects of the corresponding r-protein mutants. Our findings highlight that the acquisition of eukaryote-specific domains in r-proteins was accompanied by the co-evolution of proteins specialized to protect these domains and emphasize the critical role of r-protein chaperones for the synthesis of eukaryotic ribosomes.
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Affiliation(s)
- Ingrid Rössler
- Institute of Molecular Biosciences, University of Graz, Humboldtstrasse 50, 8010 Graz, Austria
- BioTechMed-Graz, Graz, Austria
| | - Julia Embacher
- Institute of Molecular Biosciences, University of Graz, Humboldtstrasse 50, 8010 Graz, Austria
- BioTechMed-Graz, Graz, Austria
| | - Benjamin Pillet
- Unit of Biochemistry, Department of Biology, University of Fribourg, Chemin du Musée 10, 1700 Fribourg, Switzerland
| | - Guillaume Murat
- Unit of Biochemistry, Department of Biology, University of Fribourg, Chemin du Musée 10, 1700 Fribourg, Switzerland
| | - Laura Liesinger
- BioTechMed-Graz, Graz, Austria
- Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria
- Omics Center Graz, BioTechMed-Graz, Graz, Austria
| | - Jutta Hafner
- Institute of Molecular Biosciences, University of Graz, Humboldtstrasse 50, 8010 Graz, Austria
- BioTechMed-Graz, Graz, Austria
| | - Julia Judith Unterluggauer
- Institute of Molecular Biosciences, University of Graz, Humboldtstrasse 50, 8010 Graz, Austria
- BioTechMed-Graz, Graz, Austria
| | - Ruth Birner-Gruenberger
- BioTechMed-Graz, Graz, Austria
- Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria
- Omics Center Graz, BioTechMed-Graz, Graz, Austria
| | - Dieter Kressler
- Unit of Biochemistry, Department of Biology, University of Fribourg, Chemin du Musée 10, 1700 Fribourg, Switzerland
| | - Brigitte Pertschy
- Institute of Molecular Biosciences, University of Graz, Humboldtstrasse 50, 8010 Graz, Austria
- BioTechMed-Graz, Graz, Austria
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28
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Tetrapeptide 60-63 of human ribosomal protein uS3 is crucial for translation initiation. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2019; 1862:194411. [PMID: 31356988 DOI: 10.1016/j.bbagrm.2019.194411] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 07/16/2019] [Accepted: 07/16/2019] [Indexed: 12/14/2022]
Abstract
Conserved ribosomal protein uS3 contains a decapeptide fragment in positions 55-64 (human numbering), which has a very specific ability to cross-link to various RNA derivatives bearing aldehyde groups, likely provided by K62. It has been shown that during translation in the cell-free protein-synthesizing system, uS3 becomes accessible for such cross-linking only after eIF3j leaves the mRNA binding channel of the 40S ribosomal subunit. We studied the functional role of K62 and its nearest neighbors in the ribosomal assembly and translation with the use of HEK293T-derived cell cultures capable of producing FLAG-tagged uS3 (uS3FLAG) or its mutant form with amino acid residues at positions 60-63 replaced with alanines. Analysis of polysome profiles from the respective cells and cytosol lysates showed that the mutation significantly affected the uS3 ability to participate in the assembly of 40S subunits, but it was not essential for their maturation and did not prevent the binding of mRNAs to 40S subunits during translation initiation. The most striking effect of the replacement of amino acid residues in the above uS3 positions was that it almost completely deprived the 40S subunits of their ability to form 80S ribosomes, suggesting that the 48S pre-initiation complexes assembled on these subunits were defective in the binding of 60S subunits. Thus, our results revealed the previously unknown crucial role of the uS3 tetrapeptide 60GEKG63 in translation initiation related to maintaining the proper structure of the 48S complex, most likely via the prevention of premature mRNA loading into the ribosomal channel.
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29
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Espinar-Marchena F, Rodríguez-Galán O, Fernández-Fernández J, Linnemann J, de la Cruz J. Ribosomal protein L14 contributes to the early assembly of 60S ribosomal subunits in Saccharomyces cerevisiae. Nucleic Acids Res 2019; 46:4715-4732. [PMID: 29788267 PMCID: PMC5961077 DOI: 10.1093/nar/gky123] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Accepted: 02/12/2018] [Indexed: 12/11/2022] Open
Abstract
The contribution of most ribosomal proteins to ribosome synthesis has been quite well analysed in Saccharomyces cerevisiae. However, few yeast ribosomal proteins still await characterization. Herein, we show that L14, an essential 60S ribosomal protein, assembles in the nucleolus at an early stage into pre-60S particles. Depletion of L14 results in a deficit in 60S subunits and defective processing of 27SA2 and 27SA3 to 27SB pre-rRNAs. As a result, 27S pre-rRNAs are subjected to turnover and export of pre-60S particles is blocked. These phenotypes likely appear as the direct consequence of the reduced pre-60S particle association not only of L14 upon its depletion but also of a set of neighboring ribosomal proteins located at the solvent interface of 60S subunits and the adjacent region surrounding the polypeptide exit tunnel. These pre-60S intermediates also lack some essential trans-acting factors required for 27SB pre-rRNA processing but accumulate practically all factors required for processing of 27SA3 pre-rRNA. We have also analysed the functional interaction between the eukaryote-specific carboxy-terminal extensions of the neighboring L14 and L16 proteins. Our results indicate that removal of the most distal parts of these extensions cause slight translation alterations in mature 60S subunits.
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Affiliation(s)
- Francisco Espinar-Marchena
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, and Departamento de Genética, Universidad de Sevilla, Seville, Spain. Avda. Manuel Siurot, E-41013 Seville, Spain
| | - Olga Rodríguez-Galán
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, and Departamento de Genética, Universidad de Sevilla, Seville, Spain. Avda. Manuel Siurot, E-41013 Seville, Spain
| | - José Fernández-Fernández
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, and Departamento de Genética, Universidad de Sevilla, Seville, Spain. Avda. Manuel Siurot, E-41013 Seville, Spain
| | - Jan Linnemann
- Institut für Biochemie III, Universität Regensburg, 93053, Regensburg, Germany
| | - Jesús de la Cruz
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, and Departamento de Genética, Universidad de Sevilla, Seville, Spain. Avda. Manuel Siurot, E-41013 Seville, Spain
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30
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Ahmed YL, Thoms M, Mitterer V, Sinning I, Hurt E. Crystal structures of Rea1-MIDAS bound to its ribosome assembly factor ligands resembling integrin-ligand-type complexes. Nat Commun 2019; 10:3050. [PMID: 31296859 PMCID: PMC6624252 DOI: 10.1038/s41467-019-10922-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 06/10/2019] [Indexed: 01/08/2023] Open
Abstract
The Rea1 AAA+-ATPase dislodges assembly factors from pre-60S ribosomes upon ATP hydrolysis, thereby driving ribosome biogenesis. Here, we present crystal structures of Rea1-MIDAS, the conserved domain at the tip of the flexible Rea1 tail, alone and in complex with its substrate ligands, the UBL domains of Rsa4 or Ytm1. These complexes have structural similarity to integrin α-subunit domains when bound to extracellular matrix ligands, which for integrin biology is a key determinant for force-bearing cell-cell adhesion. However, the presence of additional motifs equips Rea1-MIDAS for its tasks in ribosome maturation. One loop insert cofunctions as an NLS and to activate the mechanochemical Rea1 cycle, whereas an additional β-hairpin provides an anchor to hold the ligand UBL domains in place. Our data show the versatility of the MIDAS fold for mechanical force transmission in processes as varied as integrin-mediated cell adhesion and mechanochemical removal of assembly factors from pre-ribosomes.
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Affiliation(s)
| | - Matthias Thoms
- Heidelberg University Biochemistry Center, D-69120, Heidelberg, Germany.,Gene Center, University of Munich, D-81377, Munich, Germany
| | - Valentin Mitterer
- Heidelberg University Biochemistry Center, D-69120, Heidelberg, Germany
| | - Irmgard Sinning
- Heidelberg University Biochemistry Center, D-69120, Heidelberg, Germany.
| | - Ed Hurt
- Heidelberg University Biochemistry Center, D-69120, Heidelberg, Germany.
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31
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Knüppel R, Christensen RH, Gray FC, Esser D, Strauß D, Medenbach J, Siebers B, MacNeill SA, LaRonde N, Ferreira-Cerca S. Insights into the evolutionary conserved regulation of Rio ATPase activity. Nucleic Acids Res 2019; 46:1441-1456. [PMID: 29237037 PMCID: PMC5815136 DOI: 10.1093/nar/gkx1236] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Accepted: 12/01/2017] [Indexed: 12/24/2022] Open
Abstract
Eukaryotic ribosome biogenesis is a complex dynamic process which requires the action of numerous ribosome assembly factors. Among them, the eukaryotic Rio protein family members (Rio1, Rio2 and Rio3) belong to an ancient conserved atypical protein kinase/ ATPase family required for the maturation of the small ribosomal subunit (SSU). Recent structure–function analyses suggested an ATPase-dependent role of the Rio proteins to regulate their dynamic association with the nascent pre-SSU. However, the evolutionary origin of this feature and the detailed molecular mechanism that allows controlled activation of the catalytic activity remained to be determined. In this work we provide functional evidence showing a conserved role of the archaeal Rio proteins for the synthesis of the SSU in archaea. Moreover, we unravel a conserved RNA-dependent regulation of the Rio ATPases, which in the case of Rio2 involves, at least, helix 30 of the SSU rRNA and the P-loop lysine within the shared RIO domain. Together, our study suggests a ribosomal RNA-mediated regulatory mechanism enabling the appropriate stimulation of Rio2 catalytic activity and subsequent release of Rio2 from the nascent pre-40S particle. Based on our findings we propose a unified release mechanism for the Rio proteins.
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Affiliation(s)
- Robert Knüppel
- Biochemistry III - Institute for Biochemistry, Genetics and Microbiology, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany
| | - Regitse H Christensen
- Department of Biology, University of Copenhagen, Copenhagen Biocenter, University of Copenhagen, Ole Maaløes Vej 5, 2200 Copenhagen N, Denmark
| | - Fiona C Gray
- Department of Biology, University of Copenhagen, Copenhagen Biocenter, University of Copenhagen, Ole Maaløes Vej 5, 2200 Copenhagen N, Denmark
| | - Dominik Esser
- Molecular Enzyme Technology and Biochemistry, Biofilm Centre, Faculty of Chemistry, University of Duisburg-Essen, Universitätsstraße 5, 45141 Essen, Germany
| | - Daniela Strauß
- Biochemistry I - Institute for Biochemistry, Genetics and Microbiology, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany
| | - Jan Medenbach
- Biochemistry I - Institute for Biochemistry, Genetics and Microbiology, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany
| | - Bettina Siebers
- Molecular Enzyme Technology and Biochemistry, Biofilm Centre, Faculty of Chemistry, University of Duisburg-Essen, Universitätsstraße 5, 45141 Essen, Germany
| | - Stuart A MacNeill
- Department of Biology, University of Copenhagen, Copenhagen Biocenter, University of Copenhagen, Ole Maaløes Vej 5, 2200 Copenhagen N, Denmark.,School of Biology, University of St Andrews, North Haugh, St Andrews KY16 9ST, UK
| | - Nicole LaRonde
- Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA University of Maryland Marlene and Stewart Greenebaum Cancer Center, Baltimore, MD 21201, USA
| | - Sébastien Ferreira-Cerca
- Biochemistry III - Institute for Biochemistry, Genetics and Microbiology, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany
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Mitterer V, Shayan R, Ferreira-Cerca S, Murat G, Enne T, Rinaldi D, Weigl S, Omanic H, Gleizes PE, Kressler D, Plisson-Chastang C, Pertschy B. Conformational proofreading of distant 40S ribosomal subunit maturation events by a long-range communication mechanism. Nat Commun 2019; 10:2754. [PMID: 31227701 PMCID: PMC6588571 DOI: 10.1038/s41467-019-10678-z] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Accepted: 05/23/2019] [Indexed: 12/21/2022] Open
Abstract
Eukaryotic ribosomes are synthesized in a hierarchical process driven by a plethora of assembly factors, but how maturation events at physically distant sites on pre-ribosomes are coordinated is poorly understood. Using functional analyses and cryo-EM, we show that ribosomal protein Rps20 orchestrates communication between two multi-step maturation events across the pre-40S subunit. Our study reveals that during pre-40S maturation, formation of essential contacts between Rps20 and Rps3 permits assembly factor Ltv1 to recruit the Hrr25 kinase, thereby promoting Ltv1 phosphorylation. In parallel, a deeply buried Rps20 loop reaches to the opposite pre-40S side, where it stimulates Rio2 ATPase activity. Both cascades converge to the final maturation steps releasing Rio2 and phosphorylated Ltv1. We propose that conformational proofreading exerted via Rps20 constitutes a checkpoint permitting assembly factor release and progression of pre-40S maturation only after completion of all earlier maturation steps. The biogenesis of eukaryotic ribosomes is a multi-step process involving the action of more than 200 different ribosome assembly factors. Here the authors show that Rps20 acts as a conduit to coordinate maturation steps across the head domain of the nascent small ribosomal subunit.
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Affiliation(s)
- Valentin Mitterer
- Institute for Molecular Biosciences, University of Graz, Humboldtstrasse 50, 8010, Graz, Austria.,Biochemistry Centre, University of Heidelberg, 69120, Heidelberg, Germany
| | - Ramtin Shayan
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative, Université de Toulouse, CNRS, UPS, 118 route de Narbonne, 31062, Toulouse Cedex, France
| | - Sébastien Ferreira-Cerca
- Biochemistry III - Institute for Biochemistry, Genetics and Microbiology, University of Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany.
| | - Guillaume Murat
- Unit of Biochemistry, Department of Biology, University of Fribourg, Chemin du Musée 10, 1700, Fribourg, Switzerland
| | - Tanja Enne
- Institute for Molecular Biosciences, University of Graz, Humboldtstrasse 50, 8010, Graz, Austria
| | - Dana Rinaldi
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative, Université de Toulouse, CNRS, UPS, 118 route de Narbonne, 31062, Toulouse Cedex, France
| | - Sarah Weigl
- Institute for Molecular Biosciences, University of Graz, Humboldtstrasse 50, 8010, Graz, Austria
| | - Hajrija Omanic
- Institute for Molecular Biosciences, University of Graz, Humboldtstrasse 50, 8010, Graz, Austria
| | - Pierre-Emmanuel Gleizes
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative, Université de Toulouse, CNRS, UPS, 118 route de Narbonne, 31062, Toulouse Cedex, France
| | - Dieter Kressler
- Unit of Biochemistry, Department of Biology, University of Fribourg, Chemin du Musée 10, 1700, Fribourg, Switzerland.
| | - Celia Plisson-Chastang
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative, Université de Toulouse, CNRS, UPS, 118 route de Narbonne, 31062, Toulouse Cedex, France.
| | - Brigitte Pertschy
- Institute for Molecular Biosciences, University of Graz, Humboldtstrasse 50, 8010, Graz, Austria.
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Communication between RACK1/Asc1 and uS3 (Rps3) is essential for RACK1/Asc1 function in yeast Saccharomyces cerevisiae. Gene 2019; 706:69-76. [PMID: 31054365 DOI: 10.1016/j.gene.2019.04.087] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2019] [Revised: 04/10/2019] [Accepted: 04/30/2019] [Indexed: 01/03/2023]
Abstract
The receptor for activated c-kinase (RACK1, Asc1 in yeast) is a eukaryotic ribosomal protein located in the head region of the 40S subunit near the mRNA exit channel. This WD-repeat β-propeller protein acts as a signaling molecule and is involved in metabolic regulation, cell cycle progression, and translational control. However, the exact details of the RACK1 recruitment and stable association with the 40S ribosomal subunit remain only partially known. X-ray analyses of the yeast, Saccharomyces cerevisiae, ribosome revealed that the RACK1 propeller blade (4-5) interacts with the eukaryote-specific C-terminal domain (CTD) of ribosomal protein S3 (uS3 family). To check the functional significance of this interaction, we generated mutant yeast strains harboring C-terminal deletions of uS3. We found that deletion of the 20 C-terminal residues (interacting with blade 4-5) from the uS3-CTD abrogates RACK1 binding to the ribosome. Strains with truncated uS3-CTD exhibited compromised cellular growth and protein synthesis similar to that of RACK1Δ strain, thus suggesting that the uS3-CTD is crucial not only for the recruitment and association of RACK1 with the ribosome, but also for its intracellular function. We suggest that eukaryote-specific RACK1-uS3 interaction has evolved to act as a link between the ribosome and the cellular signaling pathways.
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Peng H, Zhao Y, Chen J, Huo J, Zhang Y, Xiao T. Knockdown of ribosomal protein S3 causes preimplantation developmental arrest in mice. Theriogenology 2019; 129:77-81. [PMID: 30826720 DOI: 10.1016/j.theriogenology.2019.02.022] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 01/09/2019] [Accepted: 02/22/2019] [Indexed: 01/05/2023]
Abstract
Ribosomal protein S3 (RpS3), a member of the ribosome 40S subunit, has conventional ribosomal function and additional extraribosomal functions. The aim of the present study was to analyze the expression and localization of RpS3 and its function in early embryogenesis in mice. RpS3 mRNA and protein were expressed in multiple mouse tissues. In the ovary, RpS3 protein was ubiquitously and highly expressed in oocytes and granulosa cells. After ovulation and fertilization, RpS3 mRNA and protein were detected in oocytes and preimplantation embryos. Furthermore, RpS3 protein was localized in the cytoplasm of oocytes and preimplantation embryos. Moreover, knockdown of RpS3 in zygotes led to a significantly decreased rate of blastocyst formation. These results provide the first evidence for a novel function of RpS3 in regulating early embryonic development in mice.
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Affiliation(s)
- Hui Peng
- College of Animal Science, Fujian Agriculture and Forestry University, Fujian, Fuzhou, 350002, PR China; University Key Lab for Integrated Chinese Traditional and Western Veterinary Medicine and Animal Healthcare in Fujian Province, Fujian Agriculture and Forestry University, Fujian, Fuzhou, 350002, PR China
| | - Yifan Zhao
- College of Animal Science, Fujian Agriculture and Forestry University, Fujian, Fuzhou, 350002, PR China
| | - Jing Chen
- College of Animal Science, Fujian Agriculture and Forestry University, Fujian, Fuzhou, 350002, PR China
| | - Jianchao Huo
- College of Animal Science, Fujian Agriculture and Forestry University, Fujian, Fuzhou, 350002, PR China
| | - Yanyan Zhang
- College of Animal Science, Fujian Agriculture and Forestry University, Fujian, Fuzhou, 350002, PR China
| | - Tianfang Xiao
- College of Animal Science, Fujian Agriculture and Forestry University, Fujian, Fuzhou, 350002, PR China.
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35
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Linnemann J, Pöll G, Jakob S, Ferreira-Cerca S, Griesenbeck J, Tschochner H, Milkereit P. Impact of two neighbouring ribosomal protein clusters on biogenesis factor binding and assembly of yeast late small ribosomal subunit precursors. PLoS One 2019; 14:e0203415. [PMID: 30653518 PMCID: PMC6336269 DOI: 10.1371/journal.pone.0203415] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Accepted: 01/01/2019] [Indexed: 11/25/2022] Open
Abstract
Many of the small ribosomal subunit proteins are required for the stabilisation of late small ribosomal subunit (SSU) precursors and for final SSU rRNA processing in S. cerevisiae. Among them are ribosomal proteins (r-proteins) which form a protein cluster around rpS0 (uS2) at the "neck" of the SSU (S0-cluster) and others forming a nearby protein cluster around rpS3 (uS3) at the SSU "beak". Here we applied semi-quantitative proteomics together with complementary biochemical approaches to study how incomplete assembly of these two r-protein clusters affects binding and release of SSU maturation factors and assembly of other r-proteins in late SSU precursors in S. cerevisiae. For each of the two clusters specific impairment of the local r-protein assembly state was observed in Rio2 associated SSU precursors. Besides, cluster-specific effects on the association of biogenesis factors were detected. These suggested a role of S0-cluster formation for the efficient release of the two nuclear export factors Rrp12 and Slx9 from SSU precursors and for the correct incorporation of the late acting biogenesis factor Rio2. Based on our and on previous results we propose the existence of at least two different r-protein assembly checkpoints during late SSU maturation in S. cerevisiae. We discuss in the light of recent SSU precursor structure models how r-protein assembly states might be sensed by biogenesis factors at the S0-cluster checkpoint.
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Affiliation(s)
- Jan Linnemann
- Lehrstuhl für Biochemie III, Universität Regensburg, Regensburg, Germany
| | - Gisela Pöll
- Lehrstuhl für Biochemie III, Universität Regensburg, Regensburg, Germany
| | - Steffen Jakob
- Lehrstuhl für Biochemie III, Universität Regensburg, Regensburg, Germany
| | | | - Joachim Griesenbeck
- Lehrstuhl für Biochemie III, Universität Regensburg, Regensburg, Germany
- * E-mail: (JG); (HT); (PM)
| | - Herbert Tschochner
- Lehrstuhl für Biochemie III, Universität Regensburg, Regensburg, Germany
- * E-mail: (JG); (HT); (PM)
| | - Philipp Milkereit
- Lehrstuhl für Biochemie III, Universität Regensburg, Regensburg, Germany
- * E-mail: (JG); (HT); (PM)
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36
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Ochkasova AS, Meschaninova MI, Venyaminova AG, Ivanov AV, Graifer DM, Karpova GG. The human ribosome can interact with the abasic site in mRNA via a specific peptide of the uS3 protein located near the mRNA entry channel. Biochimie 2018; 158:117-125. [PMID: 30594661 DOI: 10.1016/j.biochi.2018.12.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 12/25/2018] [Indexed: 12/12/2022]
Abstract
The small subunit ribosomal protein uS3 is a critically important player in the ribosome-mRNA interactions during translation and has numerous functions not directly related to protein synthesis in eukaryotes. A peculiar feature of the human uS3 protein is the ability of its fragment 55-64 exposed on the 40S subunit surface near the mRNA entry channel to form cross-links with 3'-terminal dialdehyde derivatives of various unstructured RNAs and with abasic sites in single-stranded DNAs. Here we showed that the ability of the above uS3 fragment to cross-link to abasic sites in DNAs is inherent only in mature cytoplasmic 40S subunits, but not nuclear pre-40S particles, which implies that it may be relevant to the ribosome-mRNA interplay. To clarify this issue, we investigated interactions of human ribosomes with synthetic mRNA analogues bearing an abasic site protected by a photocleavable group at the 3'-termini. We found that these mRNA analogues can form specific complexes with 80S ribosomes and 40S subunits, where the undamaged upstream part of the analogue is fixed in the mRNA binding channel by interaction with the P-site tRNA, and the downstream part located outside the ribosome is cross-linked to the uS3 fragment 55-64. The yield of cross-links of the mRNA analogues was rather high when their undamaged parts were bound to the mRNA channel prior to deprotection of the abasic site enabling its covalent attachment to the 40S subunit via the uS3 protein, but not vice versa. Based on our findings, one can assume that abasic sites, which can occur in mRNAs due to oxidative stress and ageing, are able to interact directly with the uS3 fragment exposed on the 40S subunit surface near the mRNA entry channel during translation. Consequently, the 40S subunit can be considered as a potential mRNA quality controller.
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Affiliation(s)
- Anastasia S Ochkasova
- Institute of Chemical Biology and Fundamental Medicine SB RAS, Novosibirsk, 630090, Russia
| | - Maria I Meschaninova
- Institute of Chemical Biology and Fundamental Medicine SB RAS, Novosibirsk, 630090, Russia
| | - Aliya G Venyaminova
- Institute of Chemical Biology and Fundamental Medicine SB RAS, Novosibirsk, 630090, Russia
| | - Anton V Ivanov
- Institute of Chemical Biology and Fundamental Medicine SB RAS, Novosibirsk, 630090, Russia
| | - Dmitri M Graifer
- Institute of Chemical Biology and Fundamental Medicine SB RAS, Novosibirsk, 630090, Russia; Novosibirsk State University, Novosibirsk, 630090, Russia
| | - Galina G Karpova
- Institute of Chemical Biology and Fundamental Medicine SB RAS, Novosibirsk, 630090, Russia; Novosibirsk State University, Novosibirsk, 630090, Russia.
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37
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Cerezo E, Plisson-Chastang C, Henras AK, Lebaron S, Gleizes PE, O'Donohue MF, Romeo Y, Henry Y. Maturation of pre-40S particles in yeast and humans. WILEY INTERDISCIPLINARY REVIEWS-RNA 2018; 10:e1516. [PMID: 30406965 DOI: 10.1002/wrna.1516] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 09/02/2018] [Accepted: 10/01/2018] [Indexed: 12/22/2022]
Abstract
The synthesis of ribosomal subunits in eukaryotes requires the interplay of numerous maturation and assembly factors (AFs) that intervene in the insertion of ribosomal proteins within pre-ribosomal particles, the ribosomal subunit precursors, as well as in pre-ribosomal RNA (rRNA) processing and folding. Here, we review the intricate nuclear and cytoplasmic maturation steps of pre-40S particles, the precursors to the small ribosomal subunits, in both yeast and human cells, with particular emphasis on the timing and mechanisms of AF association with and dissociation from pre-40S particles and the roles of these AFs in the maturation process. We highlight the particularly complex pre-rRNA processing pathway in human cells, compared to yeast, to generate the mature 18S rRNA. We discuss the information gained from the recently published cryo-electron microscopy atomic models of yeast and human pre-40S particles, as well as the checkpoint/quality control systems that seem to operate to probe functional sites within yeast cytoplasmic pre-40S particles. This article is categorized under: RNA Processing > rRNA Processing Translation > Ribosome Biogenesis.
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Affiliation(s)
- Emilie Cerezo
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Célia Plisson-Chastang
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Anthony K Henras
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Simon Lebaron
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Pierre-Emmanuel Gleizes
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Marie-Françoise O'Donohue
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Yves Romeo
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Yves Henry
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
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Collins JC, Ghalei H, Doherty JR, Huang H, Culver RN, Karbstein K. Ribosome biogenesis factor Ltv1 chaperones the assembly of the small subunit head. J Cell Biol 2018; 217:4141-4154. [PMID: 30348748 PMCID: PMC6279377 DOI: 10.1083/jcb.201804163] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Revised: 08/17/2018] [Accepted: 09/20/2018] [Indexed: 11/22/2022] Open
Abstract
Collins et al. use yeast genetics, biochemistry, and structure probing to dissect the role of the assembly factor Ltv1 in 40S ribosome maturation. Ribosomes from Ltv1-deficient cells have substoichiometric amounts of Rps10 and Asc1 and misfolded head rRNA, leading to defects in translational fidelity and ribosome-mediated RNA quality control, demonstrating a role for Ltv1 in chaperoning the assembly of the subunit head. The correct assembly of ribosomes from ribosomal RNAs (rRNAs) and ribosomal proteins (RPs) is critical, as indicated by the diseases caused by RP haploinsufficiency and loss of RP stoichiometry in cancer cells. Nevertheless, how assembly of each RP is ensured remains poorly understood. We use yeast genetics, biochemistry, and structure probing to show that the assembly factor Ltv1 facilitates the incorporation of Rps3, Rps10, and Asc1/RACK1 into the small ribosomal subunit head. Ribosomes from Ltv1-deficient yeast have substoichiometric amounts of Rps10 and Asc1 and show defects in translational fidelity and ribosome-mediated RNA quality control. These defects provide a growth advantage under some conditions but sensitize the cells to oxidative stress. Intriguingly, relative to glioma cell lines, breast cancer cells have reduced levels of LTV1 and produce ribosomes lacking RPS3, RPS10, and RACK1. These data describe a mechanism to ensure RP assembly and demonstrate how cancer cells circumvent this mechanism to generate diverse ribosome populations that can promote survival under stress.
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Affiliation(s)
- Jason C Collins
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, Jupiter, FL
| | - Homa Ghalei
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, Jupiter, FL
| | - Joanne R Doherty
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, Jupiter, FL
| | - Haina Huang
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, Jupiter, FL
| | - Rebecca N Culver
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, Jupiter, FL
| | - Katrin Karbstein
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, Jupiter, FL
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39
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Gene Expression of Pneumocystis murina after Treatment with Anidulafungin Results in Strong Signals for Sexual Reproduction, Cell Wall Integrity, and Cell Cycle Arrest, Indicating a Requirement for Ascus Formation for Proliferation. Antimicrob Agents Chemother 2018; 62:AAC.02513-17. [PMID: 29463544 PMCID: PMC5923105 DOI: 10.1128/aac.02513-17] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Accepted: 02/10/2018] [Indexed: 01/03/2023] Open
Abstract
The echinocandins are a class of antifungal agents that target β-1,3-d-glucan (BG) biosynthesis. In the ascigerous Pneumocystis species, treatment with these drugs depletes the ascus life cycle stage, which contains BG, but large numbers of forms which do not express BG remain in the infected lungs. In the present study, the gene expression profiles of Pneumocystis murina were compared between infected, untreated mice and mice treated with anidulafungin for 2 weeks to understand the metabolism of the persisting forms. Almost 80 genes were significantly up- or downregulated. Like other fungi exposed to echinocandins, genes associated with sexual replication, cell wall integrity, cell cycle arrest, and stress comprised the strongest upregulated signals in P. murina from the treated mice. The upregulation of the P. murina β-1,3-d-glucan endohydrolase and endo-1,3-glucanase was notable and may explain the disappearance of the existing asci in the lungs of treated mice since both enzymes can degrade BG. The biochemical measurement of BG in the lungs of treated mice and fluorescence microscopy with an anti-BG antibody supported the loss of BG. Downregulated signals included genes involved in cell replication, genome stability, and ribosomal biogenesis and function and the Pneumocystis-specific genes encoding the major surface glycoproteins (Msg). These studies suggest that P. murina attempted to undergo sexual replication in response to a stressed environment and was halted in any type of proliferative cycle, likely due to a lack of BG. Asci appear to be a required part of the life cycle stage of Pneumocystis, and BG may be needed to facilitate progression through the life cycle via sexual replication.
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40
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Jung Y, Kim HD, Yang HW, Kim HJ, Jang CY, Kim J. Modulating cellular balance of Rps3 mono-ubiquitination by both Hel2 E3 ligase and Ubp3 deubiquitinase regulates protein quality control. Exp Mol Med 2017; 49:e390. [PMID: 29147007 PMCID: PMC5704183 DOI: 10.1038/emm.2017.128] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Revised: 03/25/2017] [Accepted: 03/27/2017] [Indexed: 12/14/2022] Open
Abstract
When a ribosome complex is stalled during the translation elongation process in eukaryotes, the mono-ubiquitination of Rps3 has recently been shown to be critical to ribosome quality control. We have discovered that the regulatory role of Rps3 mono-ubiquitination is controlled by a deubiquitinase. We also showed that an autophagic signal appears to be coupled to the mono-ubiquitination of Rps3p through the entrance of Ubp3p into the autophagosome in yeasts. The mono-ubiquitination of the Rps3 protein is tightly modulated by reciprocal action between the Hel2p E3 ligase and the Ubp3p deubiquitinase in yeasts and the reciprocal action between the RNF123 E3 ligase and the USP10 deubiquitinase in mammalian cells. We also found that the Ubp3p/USP10 deubiquitinases critically modulate Hel2p/RNF123-mediated Rps3p mono-ubiquitination. In addition, we found that Hel2p/RNF123 and Ubp3p/USP10 appeared to be differently localized in the ribosome complex after ultraviolet irradiation. Together, our results support a model in which coordinated ubiquitination and deubiquitination activities can finely balance the level of regulatory Rps3p mono-ubiquitination in ribosome-associated quality control and autophagy processes.
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Affiliation(s)
- Youjin Jung
- Laboratory of Biochemistry, Division of Life Sciences, Korea University, Seoul, Republic of Korea
| | - Hag Dong Kim
- Laboratory of Biochemistry, Division of Life Sciences, Korea University, Seoul, Republic of Korea.,HAEL Lab, TechnoComplex Building 603-3, Korea University, Seoul, Republic of Korea
| | - Hee Woong Yang
- Laboratory of Biochemistry, Division of Life Sciences, Korea University, Seoul, Republic of Korea
| | - Hye Jin Kim
- Laboratory of Biochemistry, Division of Life Sciences, Korea University, Seoul, Republic of Korea
| | - Chang-Young Jang
- Laboratory of Cell Biology, Research Center for Cell Fate Control, College of Pharmacy, Sookmyung Women's University, Seoul, Republic of Korea
| | - Joon Kim
- Laboratory of Biochemistry, Division of Life Sciences, Korea University, Seoul, Republic of Korea.,HAEL Lab, TechnoComplex Building 603-3, Korea University, Seoul, Republic of Korea
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41
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Belhabich-Baumas K, Joret C, Jády BE, Plisson-Chastang C, Shayan R, Klopp C, Henras AK, Henry Y, Mougin A. The Rio1p ATPase hinders premature entry into translation of late pre-40S pre-ribosomal particles. Nucleic Acids Res 2017; 45:10824-10836. [PMID: 28977579 PMCID: PMC5737503 DOI: 10.1093/nar/gkx734] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Accepted: 08/17/2017] [Indexed: 12/03/2022] Open
Abstract
Cytoplasmic maturation of precursors to the small ribosomal subunit in yeast requires the intervention of a dozen assembly factors (AFs), the precise roles of which remain elusive. One of these is Rio1p that seems to intervene at a late step of pre-40S particle maturation. We have investigated the role played by Rio1p in the dynamic association and dissociation of AFs with and from pre-40S particles. Our results indicate that Rio1p depletion leads to the stalling of at least 4 AFs (Nob1p, Tsr1p, Pno1p/Dim2p and Fap7p) in 80S-like particles. We conclude that Rio1p is important for the timely release of these factors from 80S-like particles. In addition, we present immunoprecipitation and electron microscopy evidence suggesting that when Rio1p is depleted, a subset of Nob1p-containing pre-40S particles associate with translating polysomes. Using Nob1p as bait, we purified pre-40S particles from cells lacking Rio1p and performed ribosome profiling experiments which suggest that immature 40S subunits can carry out translation elongation. We conclude that lack of Rio1p allows premature entry of pre-40S particles in the translation process and that the presence of Nob1p and of the 18S rRNA 3′ extension in the 20S pre-rRNA is not incompatible with translation elongation.
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Affiliation(s)
- Kamila Belhabich-Baumas
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 31000 Toulouse, France
| | - Clément Joret
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 31000 Toulouse, France
| | - Beáta E Jády
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 31000 Toulouse, France
| | - Célia Plisson-Chastang
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 31000 Toulouse, France
| | - Ramtin Shayan
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 31000 Toulouse, France
| | - Christophe Klopp
- Unité de Mathématiques et Informatique Appliquées, INRA, 31320 Castanet Tolosan, France
| | - Anthony K Henras
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 31000 Toulouse, France
| | - Yves Henry
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 31000 Toulouse, France
| | - Annie Mougin
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 31000 Toulouse, France
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Abstract
The assembly of eukaryotic ribosomes requires about 200 assembly factors promoting RNA modification, folding, cleavage, and ribosomal protein association. In this issue of Structure, Johnson et al. (2017) report structures of several late-stage intermediates of pre-40S ribosomal subunit assembly. This work provides detailed testable insights into assembly factor function.
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Eukaryotic ribosome assembly, transport and quality control. Nat Struct Mol Biol 2017; 24:689-699. [PMID: 28880863 DOI: 10.1038/nsmb.3454] [Citation(s) in RCA: 159] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Accepted: 07/27/2017] [Indexed: 12/18/2022]
Abstract
Eukaryotic ribosome synthesis is a complex, energy-consuming process that takes place across the nucleolus, nucleoplasm and cytoplasm and requires more than 200 conserved assembly factors. Here, we discuss mechanisms by which the ribosome assembly and nucleocytoplasmic transport machineries collaborate to produce functional ribosomes. We also highlight recent cryo-EM studies that provided unprecedented snapshots of ribosomes during assembly and quality control.
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Kressler D, Hurt E, Baßler J. A Puzzle of Life: Crafting Ribosomal Subunits. Trends Biochem Sci 2017; 42:640-654. [DOI: 10.1016/j.tibs.2017.05.005] [Citation(s) in RCA: 95] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 03/16/2017] [Accepted: 05/05/2017] [Indexed: 01/24/2023]
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Espinar-Marchena FJ, Babiano R, Cruz J. Placeholder factors in ribosome biogenesis: please, pave my way. MICROBIAL CELL 2017; 4:144-168. [PMID: 28685141 PMCID: PMC5425277 DOI: 10.15698/mic2017.05.572] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The synthesis of cytoplasmic eukaryotic ribosomes is an extraordinarily energy-demanding cellular activity that occurs progressively from the nucleolus to the cytoplasm. In the nucleolus, precursor rRNAs associate with a myriad of trans-acting factors and some ribosomal proteins to form pre-ribosomal particles. These factors include snoRNPs, nucleases, ATPases, GTPases, RNA helicases, and a vast list of proteins with no predicted enzymatic activity. Their coordinate activity orchestrates in a spatiotemporal manner the modification and processing of precursor rRNAs, the rearrangement reactions required for the formation of productive RNA folding intermediates, the ordered assembly of the ribosomal proteins, and the export of pre-ribosomal particles to the cytoplasm; thus, providing speed, directionality and accuracy to the overall process of formation of translation-competent ribosomes. Here, we review a particular class of trans-acting factors known as "placeholders". Placeholder factors temporarily bind selected ribosomal sites until these have achieved a structural context that is appropriate for exchanging the placeholder with another site-specific binding factor. By this strategy, placeholders sterically prevent premature recruitment of subsequently binding factors, premature formation of structures, avoid possible folding traps, and act as molecular clocks that supervise the correct progression of pre-ribosomal particles into functional ribosomal subunits. We summarize the current understanding of those factors that delay the assembly of distinct ribosomal proteins or subsequently bind key sites in pre-ribosomal particles. We also discuss recurrent examples of RNA-protein and protein-protein mimicry between rRNAs and/or factors, which have clear functional implications for the ribosome biogenesis pathway.
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Affiliation(s)
- Francisco J Espinar-Marchena
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, and Departamento de Genética, Universidad de Sevilla, E-41013, Seville, Spain
| | - Reyes Babiano
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, and Departamento de Genética, Universidad de Sevilla, E-41013, Seville, Spain.,Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, and Departamento de Genética, Universidad de Sevilla, E-41013, Seville, Spain
| | - Jesús Cruz
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, and Departamento de Genética, Universidad de Sevilla, E-41013, Seville, Spain
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46
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Pertschy B. When a ribosomal protein grows up - the ribosome assembly path of Rps3. MICROBIAL CELL (GRAZ, AUSTRIA) 2017; 4:140-143. [PMID: 28685140 PMCID: PMC5425276 DOI: 10.15698/mic2017.05.571] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Accepted: 03/09/2017] [Indexed: 11/29/2022]
Abstract
The biogenesis of ribosomes is a central process in all dividing cells. Eukaryotic ribosomes are composed of a large 60S and a small 40S subunit, each comprising a complex assembly of ribosomal RNA (rRNA) and ribosomal proteins (r-proteins). The synthesis of these constituents is spatially separated, with r-proteins being produced by translation in the cytoplasm, while rRNA is generated by transcription in the nucleus. Hence, the arrangement of r-proteins and rRNA into large ribonucleoprotein complexes requires dedicated mechanisms ensuring their encounter in the same compartment. To this end, r-proteins need to be safely delivered to the nucleus where they assemble with the rRNA. Beyond these initial challenges, the synthesis of ribosomes does not merely comprise the joining of r-proteins with rRNA, but occurs in a complex assembly line involving multiple maturation steps, including the processing and folding of rRNA. R-proteins usually have composite rRNA binding sites, with several different rRNA helices contributing to the full interaction. Not all of these interaction sites may already be accessible at the point when an r-protein is incorporated, necessitating that some of the r-protein-rRNA contacts are formed at later maturation stages. In our two recent studies, we investigated the ribosome assembly path of r-proteins in the yeast Saccharomyces cerevisiae using the small subunit r-protein S3 (Rps3) as a model. Our studies revealed intricate mechanisms to protect the protein, transport it into the nucleus, integrate it into pre-ribosomal precursor particles and promote its final stable association with 40S subunits.
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Affiliation(s)
- Brigitte Pertschy
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
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47
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Johnson MC, Ghalei H, Doxtader KA, Karbstein K, Stroupe ME. Structural Heterogeneity in Pre-40S Ribosomes. Structure 2017; 25:329-340. [PMID: 28111018 DOI: 10.1016/j.str.2016.12.011] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Revised: 11/07/2016] [Accepted: 12/21/2016] [Indexed: 11/24/2022]
Abstract
Late-stage 40S ribosome assembly is a highly regulated dynamic process that occurs in the cytoplasm, alongside the full translation machinery. Seven assembly factors (AFs) regulate and facilitate maturation, but the mechanisms through which they work remain undetermined. Here, we present a series of structures of the immature small subunit (pre-40S) determined by three-dimensional (3D) cryoelectron microscopy with 3D sorting to assess the molecule's heterogeneity. These structures demonstrate an extensive structural heterogeneity of interface AFs that likely regulates subunit joining during 40S maturation. We also present structural models for the beak and the platform, two regions where the low resolution of previous studies did not allow for localization of AFs and the rRNA, respectively. These models are supported by biochemical analyses using point variants and suggest that maturation of the 18S 3' end is regulated by dissociation of the AF Dim1 from the subunit interface, consistent with previous biochemical analyses.
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Affiliation(s)
- Matthew C Johnson
- Department of Biological Science, Institute of Molecular Biophysics, Florida State University, 91 Chieftain Way, Tallahassee, FL 32306, USA
| | - Homa Ghalei
- Department of Cancer Biology, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - Katelyn A Doxtader
- Department of Cancer Biology, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - Katrin Karbstein
- Department of Cancer Biology, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - M Elizabeth Stroupe
- Department of Biological Science, Institute of Molecular Biophysics, Florida State University, 91 Chieftain Way, Tallahassee, FL 32306, USA.
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48
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Peña C, Schütz S, Fischer U, Chang Y, Panse VG. Prefabrication of a ribosomal protein subcomplex essential for eukaryotic ribosome formation. eLife 2016; 5. [PMID: 27929371 PMCID: PMC5148605 DOI: 10.7554/elife.21755] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Accepted: 11/29/2016] [Indexed: 01/21/2023] Open
Abstract
Spatial clustering of ribosomal proteins (r-proteins) through tertiary interactions is a striking structural feature of the eukaryotic ribosome. However, the functional importance of these intricate inter-connections, and how they are established is currently unclear. Here, we reveal that a conserved ATPase, Fap7, organizes interactions between neighboring r-proteins uS11 and eS26 prior to their delivery to the earliest ribosome precursor, the 90S. In vitro, uS11 only when bound to Fap7 becomes competent to recruit eS26 through tertiary contacts found between these r-proteins on the mature ribosome. Subsequently, Fap7 ATPase activity unloads the uS11:eS26 subcomplex onto its rRNA binding site, and therefore ensures stoichiometric integration of these r-proteins into the 90S. Fap7-depletion in vivo renders uS11 susceptible to proteolysis, and precludes eS26 incorporation into the 90S. Thus, prefabrication of a native-like r-protein subcomplex drives efficient and accurate construction of the eukaryotic ribosome. DOI:http://dx.doi.org/10.7554/eLife.21755.001
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Affiliation(s)
- Cohue Peña
- Institute of Biochemistry, ETH Zurich, Zurich, Switzerland.,Institute of Medical Microbiology, University of Zurich, Zurich, Switzerland
| | - Sabina Schütz
- Institute of Medical Microbiology, University of Zurich, Zurich, Switzerland
| | - Ute Fischer
- Institute of Biochemistry, ETH Zurich, Zurich, Switzerland
| | - Yiming Chang
- Institute of Biochemistry, ETH Zurich, Zurich, Switzerland
| | - Vikram G Panse
- Institute of Medical Microbiology, University of Zurich, Zurich, Switzerland
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49
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Pillet B, Mitterer V, Kressler D, Pertschy B. Hold on to your friends: Dedicated chaperones of ribosomal proteins: Dedicated chaperones mediate the safe transfer of ribosomal proteins to their site of pre-ribosome incorporation. Bioessays 2016; 39:1-12. [PMID: 27859409 DOI: 10.1002/bies.201600153] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Eukaryotic ribosomes are assembled from their components, the ribosomal RNAs and ribosomal proteins, in a tremendously complex, multi-step process, which primarily takes place in the nuclear compartment. Therefore, most ribosomal proteins have to travel from the cytoplasm to their incorporation site on pre-ribosomes within the nucleus. However, due to their particular characteristics, such as a highly basic amino acid composition and the presence of unstructured extensions, ribosomal proteins are especially prone to aggregation and degradation in their unassembled state, hence specific mechanisms must operate to ensure their safe delivery. Recent studies have uncovered a group of proteins, termed dedicated chaperones, specialized in accompanying and guarding individual ribosomal proteins. In this essay, we review how these dedicated chaperones utilize different folds to interact with their ribosomal protein clients and how they ensure their soluble expression and interconnect their intracellular transport with their efficient assembly into pre-ribosomes.
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Affiliation(s)
- Benjamin Pillet
- Unit of Biochemistry, Department of Biology, University of Fribourg, Fribourg, Switzerland
| | - Valentin Mitterer
- Institut für Molekulare Biowissenschaften, Universität Graz, Graz, Austria
| | - Dieter Kressler
- Unit of Biochemistry, Department of Biology, University of Fribourg, Fribourg, Switzerland
| | - Brigitte Pertschy
- Institut für Molekulare Biowissenschaften, Universität Graz, Graz, Austria
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50
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Nuclear import of dimerized ribosomal protein Rps3 in complex with its chaperone Yar1. Sci Rep 2016; 6:36714. [PMID: 27819319 PMCID: PMC5098186 DOI: 10.1038/srep36714] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Accepted: 10/19/2016] [Indexed: 11/08/2022] Open
Abstract
After their cytoplasmic synthesis, ribosomal proteins need to be transported into the nucleus, where they assemble with ribosomal RNA into pre-ribosomal particles. Due to their physicochemical properties, they need protection from aggregation on this path. Newly synthesized ribosomal protein Rps3 forms a dimer that is associated with one molecule of its specific chaperone Yar1. Here we report that redundant pathways contribute to the nuclear import of Rps3, with the classical importin α/β pathway (Kap60/Kap95 in yeast) constituting a main import route. The Kap60/Kap95 heterodimer mediates efficient nuclear import of Rps3 by recognition of an N-terminal monopartite nuclear localization signal (NLS). This Rps3-NLS is located directly adjacent to the Yar1-binding site and, upon binding of Kap60 to Rps3, Yar1 is displaced from the ribosomal protein in vitro. While Yar1 does not directly interact with Kap60 in vitro, affinity purifications of Yar1 and Rps3, however, revealed that Kap60 is present in the Rps3/Yar1 complex in vivo. Indeed we could reconstitute such a protein complex containing Rps3 and both Yar1 and Kap60 in vitro. Our data suggest that binding of Yar1 to one N-domain and binding of Kap60 to the second N-domain of dimerized Rps3 orchestrates import and protection of the ribosomal protein.
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