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Zang Y, Ran X, Yuan J, Wu H, Wang Y, Li H, Teng H, Sun Z. Genomic hallmarks and therapeutic targets of ribosome biogenesis in cancer. Brief Bioinform 2024; 25:bbae023. [PMID: 38343327 PMCID: PMC10859687 DOI: 10.1093/bib/bbae023] [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: 10/26/2023] [Revised: 01/11/2024] [Accepted: 01/15/2024] [Indexed: 02/15/2024] Open
Abstract
Hyperactive ribosome biogenesis (RiboSis) fuels unrestricted cell proliferation, whereas genomic hallmarks and therapeutic targets of RiboSis in cancers remain elusive, and efficient approaches to quantify RiboSis activity are still limited. Here, we have established an in silico approach to conveniently score RiboSis activity based on individual transcriptome data. By employing this novel approach and RNA-seq data of 14 645 samples from TCGA/GTEx dataset and 917 294 single-cell expression profiles across 13 cancer types, we observed the elevated activity of RiboSis in malignant cells of various human cancers, and high risk of severe outcomes in patients with high RiboSis activity. Our mining of pan-cancer multi-omics data characterized numerous molecular alterations of RiboSis, and unveiled the predominant somatic alteration in RiboSis genes was copy number variation. A total of 128 RiboSis genes, including EXOSC4, BOP1, RPLP0P6 and UTP23, were identified as potential therapeutic targets. Interestingly, we observed that the activity of RiboSis was associated with TP53 mutations, and hyperactive RiboSis was associated with poor outcomes in lung cancer patients without TP53 mutations, highlighting the importance of considering TP53 mutations during therapy by impairing RiboSis. Moreover, we predicted 23 compounds, including methotrexate and CX-5461, associated with the expression signature of RiboSis genes. The current study generates a comprehensive blueprint of molecular alterations in RiboSis genes across cancers, which provides a valuable resource for RiboSis-based anti-tumor therapy.
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Affiliation(s)
- Yue Zang
- HIM-BGI Omics Center, Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences and Institute of Genomic Medicine, Wenzhou Medical University, China
| | - Xia Ran
- Liangzhu Laboratory, Zhejiang University Medical Center, China
| | - Jie Yuan
- BGI Education Center, University of Chinese Academy of Sciences, China
| | - Hao Wu
- Institute of Genomic Medicine, Wenzhou Medical University, China
| | - Youya Wang
- Institute of Genomic Medicine, Wenzhou Medical University, China
| | - He Li
- Institute of Genomic Medicine, Wenzhou Medical University, China
| | - Huajing Teng
- Department of Radiation Oncology, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education) at Peking University Cancer Hospital and Institute, Beijing 100142, China
| | - Zhongsheng Sun
- HIM-BGI Omics Center, Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Institute of Genomic Medicine, Wenzhou Medical University, and Beijing Institutes of Life Science, Chinese Academy of Sciences, Hangzhou, China
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2
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Marrugal Á, Ferrer I, Quintanal-Villalonga Á, Ojeda L, Pastor MD, García-Luján R, Carnero A, Paz-Ares L, Molina-Pinelo S. Inhibition of HSP90 in Driver Oncogene-Defined Lung Adenocarcinoma Cell Lines: Key Proteins Underpinning Therapeutic Efficacy. Int J Mol Sci 2023; 24:13830. [PMID: 37762133 PMCID: PMC10530904 DOI: 10.3390/ijms241813830] [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: 08/21/2023] [Revised: 09/04/2023] [Accepted: 09/06/2023] [Indexed: 09/29/2023] Open
Abstract
The use of 90 kDa heat shock protein (HSP90) inhibition as a therapy in lung adenocarcinoma remains limited due to moderate drug efficacy, the emergence of drug resistance, and early tumor recurrence. The main objective of this research is to maximize treatment efficacy in lung adenocarcinoma by identifying key proteins underlying HSP90 inhibition according to molecular background, and to search for potential biomarkers of response to this therapeutic strategy. Inhibition of the HSP90 chaperone was evaluated in different lung adenocarcinoma cell lines representing the most relevant molecular alterations (EGFR mutations, KRAS mutations, or EML4-ALK translocation) and wild-type genes found in each tumor subtype. The proteomic technique iTRAQ was used to identify proteomic profiles and determine which biological pathways are involved in the response to HSP90 inhibition in lung adenocarcinoma. We corroborated the greater efficacy of HSP90 inhibition in EGFR mutated or EML4-ALK translocated cell lines. We identified proteins specifically and significantly deregulated after HSP90 inhibition for each molecular alteration. Two proteins, ADI1 and RRP1, showed independently deregulated molecular patterns. Functional annotation of the altered proteins suggested that apoptosis was the only pathway affected by HSP90 inhibition across all molecular subgroups. The expression of ADI1 and RRP1 could be used to monitor the correct inhibition of HSP90 in lung adenocarcinoma. In addition, proteins such as ASS1, ITCH, or UBE2L3 involved in pathways related to the inhibition of a particular molecular background could be used as potential response biomarkers, thereby improving the efficacy of this therapeutic approach to combat lung adenocarcinoma.
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Affiliation(s)
- Ángela Marrugal
- H12O-CNIO Lung Cancer Clinical Research Unit, Instituto de Investigación Hospital 12 de Octubre & Centro Nacional de Investigaciones Oncológicas (CNIO), 28029 Madrid, Spain (L.P.-A.)
| | - Irene Ferrer
- H12O-CNIO Lung Cancer Clinical Research Unit, Instituto de Investigación Hospital 12 de Octubre & Centro Nacional de Investigaciones Oncológicas (CNIO), 28029 Madrid, Spain (L.P.-A.)
- CIBERONC, Instituto de Salud Carlos III, 28029 Madrid, Spain;
| | | | - Laura Ojeda
- H12O-CNIO Lung Cancer Clinical Research Unit, Instituto de Investigación Hospital 12 de Octubre & Centro Nacional de Investigaciones Oncológicas (CNIO), 28029 Madrid, Spain (L.P.-A.)
| | - María Dolores Pastor
- Instituto de Biomedicina de Sevilla (IBiS) (HUVR, CSIC, Universidad de Sevilla), 41013 Sevilla, Spain
| | - Ricardo García-Luján
- Respiratory Department, Hospital Universitario Doce de Octubre, 28041 Madrid, Spain
| | - Amancio Carnero
- CIBERONC, Instituto de Salud Carlos III, 28029 Madrid, Spain;
- Instituto de Biomedicina de Sevilla (IBiS) (HUVR, CSIC, Universidad de Sevilla), 41013 Sevilla, Spain
| | - Luis Paz-Ares
- H12O-CNIO Lung Cancer Clinical Research Unit, Instituto de Investigación Hospital 12 de Octubre & Centro Nacional de Investigaciones Oncológicas (CNIO), 28029 Madrid, Spain (L.P.-A.)
- CIBERONC, Instituto de Salud Carlos III, 28029 Madrid, Spain;
- Medical Oncology Department, Hospital Universitario Doce de Octubre, 28041 Madrid, Spain
- Medical School, Universidad Complutense, 28040 Madrid, Spain
| | - Sonia Molina-Pinelo
- CIBERONC, Instituto de Salud Carlos III, 28029 Madrid, Spain;
- Instituto de Biomedicina de Sevilla (IBiS) (HUVR, CSIC, Universidad de Sevilla), 41013 Sevilla, Spain
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3
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Halbout M, Bury M, Hanet A, Gerin I, Graff J, Killian T, Gatto L, Vertommen D, Bommer GT. SUZ domain-containing proteins have multiple effects on nonsense-mediated decay target transcripts. J Biol Chem 2023; 299:105095. [PMID: 37507022 PMCID: PMC10470013 DOI: 10.1016/j.jbc.2023.105095] [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: 01/31/2023] [Revised: 07/13/2023] [Accepted: 07/14/2023] [Indexed: 07/30/2023] Open
Abstract
Many transcripts are targeted by nonsense-mediated decay (NMD), leading to their degradation and the inhibition of their translation. We found that the protein SUZ domain-containing protein 1 (SZRD1) interacts with the key NMD factor up-frameshift 1. When recruited to NMD-sensitive reporter gene transcripts, SZRD1 increased protein production, at least in part, by relieving translational inhibition. The conserved SUZ domain in SZRD1 was required for this effect. The SUZ domain is present in only three other human proteins besides SZRD1: R3H domain-containing protein 1 and 2 (R3HDM1, R3HDM2) and cAMP-regulated phosphoprotein 21 (ARPP21). We found that ARPP21, similarly to SZRD1, can increase protein production from NMD-sensitive reporter transcripts in an SUZ domain-dependent manner. This indicated that the SUZ domain-containing proteins could prevent translational inhibition of transcripts targeted by NMD. Consistent with the idea that SZRD1 mainly prevents translational inhibition, we did not observe a systematic decrease in the abundance of NMD targets when we knocked down SZRD1. Surprisingly, knockdown of SZRD1 in two different cell lines led to reduced levels of the NMD component UPF3B, which was accompanied by increased levels in a subset of NMD targets. This suggests that SZRD1 is required to maintain normal UPF3B levels and indicates that the effect of SZRD1 on NMD targets is not limited to a relief from translational inhibition. Overall, our study reveals that human SUZ domain-containing proteins play a complex role in regulating protein output from transcripts targeted by NMD.
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Affiliation(s)
- Mathias Halbout
- Department of Physiological Chemistry, de Duve Institute, UCLouvain, Brussels, Belgium; WELBIO, Brussels, Belgium
| | - Marina Bury
- Department of Physiological Chemistry, de Duve Institute, UCLouvain, Brussels, Belgium; WELBIO, Brussels, Belgium
| | - Aoife Hanet
- Department of Physiological Chemistry, de Duve Institute, UCLouvain, Brussels, Belgium
| | - Isabelle Gerin
- Department of Physiological Chemistry, de Duve Institute, UCLouvain, Brussels, Belgium; WELBIO, Brussels, Belgium
| | - Julie Graff
- Department of Physiological Chemistry, de Duve Institute, UCLouvain, Brussels, Belgium; WELBIO, Brussels, Belgium
| | - Theodore Killian
- Computational Biology Laboratory, de Duve Institute, UCLouvain, Bruxelles, Belgium
| | - Laurent Gatto
- Computational Biology Laboratory, de Duve Institute, UCLouvain, Bruxelles, Belgium
| | - Didier Vertommen
- Protein Phosphorylation Unit, de Duve Institute, UCLouvain, Brussels, Belgium
| | - Guido T Bommer
- Department of Physiological Chemistry, de Duve Institute, UCLouvain, Brussels, Belgium; WELBIO, Brussels, Belgium.
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Moraleva A, Deryabin A, Kordyukova M, Polzikov M, Shishova K, Dobrochaeva K, Rubtsov Y, Rubtsova M, Dontsova O, Zatsepina O. Human nucleolar protein SURF6/RRP14 participates in early steps of pre-rRNA processing. PLoS One 2023; 18:e0285833. [PMID: 37450438 PMCID: PMC10348582 DOI: 10.1371/journal.pone.0285833] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Accepted: 05/02/2023] [Indexed: 07/18/2023] Open
Abstract
The biogenesis of ribosomes requires tightly controlled transcription and processing of pre-rRNA which comprises ribosomal RNAs forming the core of large and small ribosomal subunits. Early steps of the pre-rRNA processing and assembly of the ribosomal subunits require a large set of proteins that perform folding and nucleolytic cleavage of pre-rRNAs in the nucleoli. Structure and functions of proteins involved in the pre-rRNA processing have been extensively studied in the budding yeast S. cerevisiae. Functional characterization of their human homologues is complicated by the complexity of mammalian ribosomes and increased number of protein factors involved in the ribosomal biogenesis. Homologues of human nucleolar protein SURF6 from yeast and mouse, Rrp14 and Surf6, respectively, had been shown to be involved in the early steps of pre-rRNA processing. Rrp14 works as RNA chaperone in complex with proteins Ssf1 and Rrp15. Human SURF6 knockdown and overexpression were used to clarify a role of SURF6 in the early steps of pre-rRNA processing in human cell lines HeLa and HTC116. By analyzing the abundance of the rRNA precursors in cells with decreased level or overexpression of SURF6, we demonstrated that human SURF6 is involved in the maturation of rRNAs from both small and large ribosomal subunits. Changes in the SURF6 level caused by knockdown or overexpression of the protein do not result in the death of HeLa cells in contrast to murine embryonic fibroblasts, but significantly alter the distribution of cells among the phases of the cell cycle. SURF6 knockdown in both p53 sufficient and p53 deficient HCT116 human cancer cells results in elongation of G0/G1 and shortening of G2/M phase. This surprising result suggests p53 independence of SURF6 effects on the cell cycle and possible multiple functions of SURF6. Our data point to the shift from pathway 1 to pathway 2 of the rRNA biogenesis caused by the SURF6 knockdown and its likely association with p53 pathway.
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Affiliation(s)
- Anastasiia Moraleva
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Moscow, Russian Federation
| | - Alexander Deryabin
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Moscow, Russian Federation
| | - Maria Kordyukova
- Federal Center of Brain Research and Neurotechnologies of the Federal Medical Biological Agency, Moscow, Russian Federation
| | - Mikhail Polzikov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Moscow, Russian Federation
| | - Kseniya Shishova
- Federal Center of Brain Research and Neurotechnologies of the Federal Medical Biological Agency, Moscow, Russian Federation
| | - Kira Dobrochaeva
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Moscow, Russian Federation
| | - Yury Rubtsov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Moscow, Russian Federation
| | - Maria Rubtsova
- Department of Chemistry, Lomonosov Moscow State University, Moscow, Russian Federation
| | - Olga Dontsova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Moscow, Russian Federation
- Department of Chemistry, Lomonosov Moscow State University, Moscow, Russian Federation
- SkolTech, Moscow, Russian Federation
| | - Olga Zatsepina
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Moscow, Russian Federation
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5
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Liskovykh M, Petrov NS, Noskov VN, Masumoto H, Earnshaw WC, Schlessinger D, Shabalina SA, Larionov V, Kouprina N. Actively transcribed rDNA and distal junction (DJ) sequence are involved in association of NORs with nucleoli. Cell Mol Life Sci 2023; 80:121. [PMID: 37043028 PMCID: PMC10097779 DOI: 10.1007/s00018-023-04770-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 03/27/2023] [Accepted: 03/28/2023] [Indexed: 04/13/2023]
Abstract
Although they are organelles without a limiting membrane, nucleoli have an exclusive structure, built upon the rDNA-rich acrocentric short arms of five human chromosomes (nucleolar organizer regions or NORs). This has raised the question: what are the structural features of a chromosome required for its inclusion in a nucleolus? Previous work has suggested that sequences adjacent to the tandemly repeated rDNA repeat units (DJ, distal junction sequence) may be involved, and we have extended such studies by addressing several issues related to the requirements for the association of NORs with nucleoli. We exploited both a set of somatic cell hybrids containing individual human acrocentric chromosomes and a set of Human Artificial Chromosomes (HACs) carrying different parts of a NOR, including an rDNA unit or DJ or PJ (proximal junction) sequence. Association of NORs with nucleoli was increased when constituent rDNA was transcribed and may be also affected by the status of heterochromatin blocks formed next to the rDNA arrays. Furthermore, our data suggest that a relatively small size DJ region, highly conserved in evolution, is also involved, along with the rDNA repeats, in the localization of p-arms of acrocentric chromosomes in nucleoli. Thus, we infer a cooperative action of rDNA sequence-stimulated by its activity-and sequences distal to rDNA contributing to incorporation into nucleoli. Analysis of NOR sequences also identified LncRNA_038958 in the DJ, a candidate transcript with the region of the suggested promoter that is located close to the DJ/rDNA boundary and contains CTCF binding sites. This LncRNA may affect RNA Polymerase I and/or nucleolar activity. Our findings provide the basis for future studies to determine which RNAs and proteins interact critically with NOR sequences to organize the higher-order structure of nucleoli and their function in normal cells and pathological states.
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Affiliation(s)
- Mikhail Liskovykh
- Developmental Therapeutics Branch, National Cancer Institute, NIH, Bethesda, MD, 20892, USA.
| | - Nikolai S Petrov
- Developmental Therapeutics Branch, National Cancer Institute, NIH, Bethesda, MD, 20892, USA
| | - Vladimir N Noskov
- Developmental Therapeutics Branch, National Cancer Institute, NIH, Bethesda, MD, 20892, USA
| | - Hiroshi Masumoto
- Laboratory of Chromosome Engineering, Department of Frontier Research and Development, Kazusa DNA Research Institute, Kisarazu, Chiba, 292-0818, Japan
| | - William C Earnshaw
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, EH9 3JR, Scotland, UK
| | - David Schlessinger
- National Institute on Aging, Laboratory of Genetics and Genomics, NIH, Baltimore, MD, 21224, USA
| | - Svetlana A Shabalina
- National Center for Biotechnology Information, National Library of Medicine, NIH, Bethesda, MD, 20892, USA
| | - Vladimir Larionov
- Developmental Therapeutics Branch, National Cancer Institute, NIH, Bethesda, MD, 20892, USA.
| | - Natalay Kouprina
- Developmental Therapeutics Branch, National Cancer Institute, NIH, Bethesda, MD, 20892, USA.
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Zhu Q, Tao B, Chen H, Shi H, Huang L, Chen J, Hu M, Lo LJ, Peng J. Rcl1 depletion impairs 18S pre-rRNA processing at the A1-site and up-regulates a cohort of ribosome biogenesis genes in zebrafish. Nucleic Acids Res 2021; 49:5743-5759. [PMID: 34019640 PMCID: PMC8191805 DOI: 10.1093/nar/gkab381] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Revised: 04/24/2021] [Accepted: 04/29/2021] [Indexed: 12/12/2022] Open
Abstract
Yeast Rcl1 is a potential endonuclease that mediates pre-RNA cleavage at the A2-site to separate 18S rRNA from 5.8S and 25S rRNAs. However, the biological function of Rcl1 in opisthokonta is poorly defined. Moreover, there is no information regarding the exact positions of 18S pre-rRNA processing in zebrafish. Here, we report that zebrafish pre-rRNA harbours three major cleavage sites in the 5′ETS, namely –477nt (A′-site), –97nt (A0-site) and the 5′ETS and 18S rRNA link (A1-site), as well as two major cleavage regions within the ITS1, namely 208–218nt (site 2) and 20–33nt (site E). We also demonstrate that depletion of zebrafish Rcl1 mainly impairs cleavage at the A1-site. Phenotypically, rcl1–/– mutants exhibit a small liver and exocrine pancreas and die before 15 days post-fertilization. RNA-seq analysis revealed that the most significant event in rcl1–/– mutants is the up-regulated expression of a cohort of genes related to ribosome biogenesis and tRNA production. Our data demonstrate that Rcl1 is essential for 18S rRNA maturation at the A1-site and for digestive organogenesis in zebrafish. Rcl1 deficiency, similar to deficiencies in other ribosome biogenesis factors, might trigger a common mechanism to upregulate the expression of genes responsible for ribosome biogenesis.
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Affiliation(s)
- Qinfang Zhu
- MOE Key Laboratory for Molecular Animal Nutrition, College of Animal Sciences, China
| | - Boxiang Tao
- MOE Key Laboratory for Molecular Animal Nutrition, College of Animal Sciences, China
| | - Hong Chen
- MOE Key Laboratory for Molecular Animal Nutrition, College of Animal Sciences, China
| | - Hui Shi
- MOE Key Laboratory for Molecular Animal Nutrition, College of Animal Sciences, China
| | - Ling Huang
- MOE Key Laboratory for Molecular Animal Nutrition, College of Animal Sciences, China
| | - Jun Chen
- College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Minjie Hu
- Department of Embryology, Carnegie Institution for Science, Baltimore, MD 21218, USA
| | - Li Jan Lo
- MOE Key Laboratory for Molecular Animal Nutrition, College of Animal Sciences, China
| | - Jinrong Peng
- MOE Key Laboratory for Molecular Animal Nutrition, College of Animal Sciences, China
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NORs on human acrocentric chromosome p-arms are active by default and can associate with nucleoli independently of rDNA. Proc Natl Acad Sci U S A 2020; 117:10368-10377. [PMID: 32332163 PMCID: PMC7229746 DOI: 10.1073/pnas.2001812117] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
A detailed description of how the genome is organized within the human nucleus is a major research goal. Nucleolar organizer regions (NORs) comprising ribosomal DNA (rDNA) arrays are located on the p-arms of the five human acrocentric chromosomes. Here we characterize the rules of engagement between NORs and nucleoli. We reveal variation in rDNA distribution, with some primary cell lines containing as many as four acrocentrics devoid of rDNA. We establish the default status of NORs as active and show that acrocentric p-arms devoid of rDNA retain nucleolar association potential. Based on our data, we propose that in diploid human cells, all 10 acrocentric chromosomes are nucleolar-associated, with involvement of non-rDNA sequences buffering against variable rDNA distribution. Nucleoli, the sites of ribosome biogenesis and the largest structures in human nuclei, form around nucleolar organizer regions (NORs) comprising ribosomal DNA (rDNA) arrays. NORs are located on the p-arms of the five human acrocentric chromosomes. Defining the rules of engagement between these p-arms and nucleoli takes on added significance as describing the three-dimensional organization of the human genome represents a major research goal. Here we used fluorescent in situ hybridization (FISH) and immuno-FISH on metaphase chromosomes from karyotypically normal primary and hTERT-immortalized human cell lines to catalog NORs in terms of their relative rDNA content and activity status. We demonstrate that a proportion of acrocentric p-arms in cell lines and from normal human donors have no detectable rDNA. Surprisingly, we found that all NORs with detectable rDNA are active, as defined by upstream binding factor loading. We determined the nucleolar association status of all NORs during interphase, and found that nucleolar association of acrocentric p-arms can occur independently of rDNA content, suggesting that sequences elsewhere on these chromosome arms drive nucleolar association. In established cancer lines, we characterize a variety of chromosomal rearrangements involving acrocentric p-arms and observe silent, rDNA-containing NORs that are dissociated from nucleoli. In conclusion, our findings indicate that within human nuclei, positioning of all 10 acrocentric chromosomes is dictated by nucleolar association. Furthermore, these nucleolar associations are buffered against interindividual variation in the distribution of rDNA.
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Sirri V, Grob A, Berthelet J, Jourdan N, Roussel P. Sirtuin 7 promotes 45S pre-rRNA cleavage at site 2 and determines the processing pathway. J Cell Sci 2019; 132:jcs228601. [PMID: 31331964 PMCID: PMC6771141 DOI: 10.1242/jcs.228601] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Accepted: 07/10/2019] [Indexed: 01/06/2023] Open
Abstract
In humans, ribosome biogenesis mainly occurs in nucleoli following two alternative pre-rRNA processing pathways differing in the order in which cleavages take place but not by the sites of cleavage. To uncover the role of the nucleolar NAD+-dependent deacetylase sirtuin 7 in the synthesis of ribosomal subunits, pre-rRNA processing was analyzed after sirtinol-mediated inhibition of sirtuin 7 activity or depletion of sirtuin 7 protein. We thus reveal that sirtuin 7 activity is a critical regulator of processing of 45S, 32S and 30S pre-rRNAs. Sirtuin 7 protein is primarily essential to 45S pre-rRNA cleavage at site 2, which is the first step of processing pathway 2. Furthermore, we demonstrate that sirtuin 7 physically interacts with Nop56 and the GAR domain of fibrillarin, and propose that this could interfere with fibrillarin-dependent cleavage. Sirtuin 7 depletion results in the accumulation of 5' extended forms of 32S pre-rRNA, and also influences the localization of fibrillarin. Thus, we establish a close relationship between sirtuin 7 and fibrillarin, which might determine the processing pathway used for ribosome biogenesis.
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Affiliation(s)
- Valentina Sirri
- Université de Paris, Unité de Biologie Fonctionnelle et Adaptative (BFA), UMR 8251, CNRS, 4 rue Marie-Andrée Lagroua Weill-Hallé, F-75013 Paris, France
| | - Alice Grob
- Department of Life Sciences, Imperial College London, London SW7 2AZ, England, UK
| | - Jérémy Berthelet
- Université de Paris, Unité de Biologie Fonctionnelle et Adaptative (BFA), UMR 8251, CNRS, 4 rue Marie-Andrée Lagroua Weill-Hallé, F-75013 Paris, France
| | - Nathalie Jourdan
- Sorbonne Université, Institut de Biologie Paris-Seine (IBPS), UMR 8256, CNRS, 9 quai St Bernard, F-75005 Paris, France
| | - Pascal Roussel
- Université de Paris, Unité de Biologie Fonctionnelle et Adaptative (BFA), UMR 8251, CNRS, 4 rue Marie-Andrée Lagroua Weill-Hallé, F-75013 Paris, France
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9
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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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10
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Yoshikawa H, Larance M, Harney DJ, Sundaramoorthy R, Ly T, Owen-Hughes T, Lamond AI. Efficient analysis of mammalian polysomes in cells and tissues using Ribo Mega-SEC. eLife 2018; 7:36530. [PMID: 30095066 PMCID: PMC6086667 DOI: 10.7554/elife.36530] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Accepted: 07/28/2018] [Indexed: 12/14/2022] Open
Abstract
We describe Ribo Mega-SEC, a powerful approach for the separation and biochemical analysis of mammalian polysomes and ribosomal subunits using Size Exclusion Chromatography and uHPLC. Using extracts from either cells, or tissues, polysomes can be separated within 15 min from sample injection to fraction collection. Ribo Mega-SEC shows translating ribosomes exist predominantly in polysome complexes in human cell lines and mouse liver tissue. Changes in polysomes are easily quantified between treatments, such as the cellular response to amino acid starvation. Ribo Mega-SEC is shown to provide an efficient, convenient and highly reproducible method for studying functional translation complexes. We show that Ribo Mega-SEC is readily combined with high-throughput MS-based proteomics to characterize proteins associated with polysomes and ribosomal subunits. It also facilitates isolation of complexes for electron microscopy and structural studies.
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Affiliation(s)
- Harunori Yoshikawa
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Mark Larance
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, United Kingdom.,Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Sydney, Australia
| | - Dylan J Harney
- Charles Perkins Centre, School of Life and Environmental Sciences, University of Sydney, Sydney, Australia
| | | | - Tony Ly
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, United Kingdom.,Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, United Kingdom
| | - Tom Owen-Hughes
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Angus I Lamond
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, United Kingdom
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11
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Prohibitin 2 localizes in nucleolus to regulate ribosomal RNA transcription and facilitate cell proliferation in RD cells. Sci Rep 2018; 8:1479. [PMID: 29367618 PMCID: PMC5784149 DOI: 10.1038/s41598-018-19917-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Accepted: 01/09/2018] [Indexed: 01/03/2023] Open
Abstract
Prohibitin 2 (PHB2), as a conserved multifunctional protein, is traditionally localized in the mitochondrial inner membrane and essential for maintenance of mitochondrial function. Here, we investigated the role of PHB2 in human rhabdomyosarcoma (RMS) RD cells and found substantial localization of PHB2 in the nucleolus. We demonstrated that PHB2 knockdown inhibited RD cell proliferation through inducing cell cycle arrest and suppressing DNA synthesis. Meanwhile, down-regulation of PHB2 also induced apoptosis and promoted differentiation in fractions of RD cells. In addition, PHB2 silencing led to altered nucleolar morphology, as observed by transmission electron microscopy, and impaired nucleolar function, as evidenced by down-regulation of 45S and 18S ribosomal RNA synthesis. Consistently, upon PHB2 knockdown, occupancy of c-Myc at the ribosomal DNA (rDNA) promoter was attenuated, while more myoblast determination protein 1 (MyoD) molecules bound to the rDNA promoter. In conclusion, our findings suggest that nucleolar PHB2 is involved in maintaining nucleolar morphology and function in RD cells by regulating a variety of transcription factors, which is likely to be one of the underlying mechanisms by which PHB2 promotes tumor proliferation and represses differentiation. Our study provides new insight into the pathogenesis of RMS and novel characterizations of the highly conserved PHB2 protein.
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12
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Scott DD, Trahan C, Zindy PJ, Aguilar LC, Delubac MY, Van Nostrand EL, Adivarahan S, Wei KE, Yeo GW, Zenklusen D, Oeffinger M. Nol12 is a multifunctional RNA binding protein at the nexus of RNA and DNA metabolism. Nucleic Acids Res 2017; 45:12509-12528. [PMID: 29069457 PMCID: PMC5716212 DOI: 10.1093/nar/gkx963] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Revised: 10/01/2017] [Accepted: 10/09/2017] [Indexed: 12/29/2022] Open
Abstract
To counteract the breakdown of genome integrity, eukaryotic cells have developed a network of surveillance pathways to prevent and resolve DNA damage. Recent data has recognized the importance of RNA binding proteins (RBPs) in DNA damage repair (DDR) pathways. Here, we describe Nol12 as a multifunctional RBP with roles in RNA metabolism and genome maintenance. Nol12 is found in different subcellular compartments-nucleoli, where it associates with ribosomal RNA and is required for efficient separation of large and small subunit precursors at site 2; the nucleoplasm, where it co-localizes with the RNA/DNA helicase Dhx9 and paraspeckles; as well as GW/P-bodies in the cytoplasm. Loss of Nol12 results in the inability of cells to recover from DNA stress and a rapid p53-independent ATR-Chk1-mediated apoptotic response. Nol12 co-localizes with DNA repair proteins in vivo including Dhx9, as well as with TOPBP1 at sites of replication stalls, suggesting a role for Nol12 in the resolution of DNA stress and maintenance of genome integrity. Identification of a complex Nol12 interactome, which includes NONO, Dhx9, DNA-PK and Stau1, further supports the protein's diverse functions in RNA metabolism and DNA maintenance, establishing Nol12 as a multifunctional RBP essential for genome integrity.
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Affiliation(s)
- Daniel D. Scott
- Institut de Recherches Cliniques de Montréal, 110 Avenue des Pins Ouest, Montréal, Québec H2W 1R7, Canada
- Faculty of Medicine, Division of Experimental Medicine, McGill University, Montréal, Québec H3A 1A3, Canada
| | - Christian Trahan
- Institut de Recherches Cliniques de Montréal, 110 Avenue des Pins Ouest, Montréal, Québec H2W 1R7, Canada
- Département de Biochimie, Faculté de Médecine, Université de Montréal, Montréal, Québec H3T 1J4, Canada
| | - Pierre J. Zindy
- Institut de Recherches Cliniques de Montréal, 110 Avenue des Pins Ouest, Montréal, Québec H2W 1R7, Canada
| | - Lisbeth C. Aguilar
- Institut de Recherches Cliniques de Montréal, 110 Avenue des Pins Ouest, Montréal, Québec H2W 1R7, Canada
| | - Marc Y. Delubac
- Institut de Recherches Cliniques de Montréal, 110 Avenue des Pins Ouest, Montréal, Québec H2W 1R7, Canada
- Département de Biochimie, Faculté de Médecine, Université de Montréal, Montréal, Québec H3T 1J4, Canada
| | - Eric L. Van Nostrand
- Department of Cellular and Molecular Medicine, University of California at San Diego, La Jolla, CA, USA; Stem Cell Program, University of California at San Diego, La Jolla, CA, USA; Institute for Genomic Medicine, University of California at San Diego, La Jolla, CA, USA
| | - Srivathsan Adivarahan
- Département de Biochimie, Faculté de Médecine, Université de Montréal, Montréal, Québec H3T 1J4, Canada
| | - Karen E. Wei
- Institut de Recherches Cliniques de Montréal, 110 Avenue des Pins Ouest, Montréal, Québec H2W 1R7, Canada
| | - Gene W. Yeo
- Department of Cellular and Molecular Medicine, University of California at San Diego, La Jolla, CA, USA; Stem Cell Program, University of California at San Diego, La Jolla, CA, USA; Institute for Genomic Medicine, University of California at San Diego, La Jolla, CA, USA
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Molecular Engineering Laboratory, A*STAR, Singapore
| | - Daniel Zenklusen
- Département de Biochimie, Faculté de Médecine, Université de Montréal, Montréal, Québec H3T 1J4, Canada
| | - Marlene Oeffinger
- Institut de Recherches Cliniques de Montréal, 110 Avenue des Pins Ouest, Montréal, Québec H2W 1R7, Canada
- Faculty of Medicine, Division of Experimental Medicine, McGill University, Montréal, Québec H3A 1A3, Canada
- Département de Biochimie, Faculté de Médecine, Université de Montréal, Montréal, Québec H3T 1J4, Canada
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13
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Mangan H, Gailín MÓ, McStay B. Integrating the genomic architecture of human nucleolar organizer regions with the biophysical properties of nucleoli. FEBS J 2017; 284:3977-3985. [PMID: 28500793 DOI: 10.1111/febs.14108] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Revised: 04/21/2017] [Accepted: 05/10/2017] [Indexed: 11/30/2022]
Abstract
Nucleoli are the sites of ribosome biogenesis and the largest membraneless subnuclear structures. They are intimately linked with growth and proliferation control and function as sensors of cellular stress. Nucleoli form around arrays of ribosomal gene (rDNA) repeats also called nucleolar organizer regions (NORs). In humans, NORs are located on the short arms of all five human acrocentric chromosomes. Multiple NORs contribute to the formation of large heterochromatin-surrounded nucleoli observed in most human cells. Here we will review recent findings about their genomic architecture. The dynamic nature of nucleoli began to be appreciated with the advent of photodynamic experiments using fluorescent protein fusions. We review more recent data on nucleoli in Xenopus germinal vesicles (GVs) which has revealed a liquid droplet-like behavior that facilitates nucleolar fusion. Further analysis in both XenopusGVs and Drosophila embryos indicates that the internal organization of nucleoli is generated by a combination of liquid-liquid phase separation and active processes involving rDNA. We will attempt to integrate these recent findings with the genomic architecture of human NORs to advance our understanding of how nucleoli form and respond to stress in human cells.
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Affiliation(s)
- Hazel Mangan
- Centre for Chromosome Biology, School of Natural Sciences, National University of Ireland Galway, Ireland
| | - Michael Ó Gailín
- Centre for Chromosome Biology, School of Natural Sciences, National University of Ireland Galway, Ireland
| | - Brian McStay
- Centre for Chromosome Biology, School of Natural Sciences, National University of Ireland Galway, Ireland
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14
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Wang Y, Zhu Q, Huang L, Zhu Y, Chen J, Peng J, Lo LJ. Interaction between Bms1 and Rcl1, two ribosome biogenesis factors, is evolutionally conserved in zebrafish and human. J Genet Genomics 2016; 43:467-9. [PMID: 27474224 DOI: 10.1016/j.jgg.2016.05.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2016] [Revised: 05/08/2016] [Accepted: 05/08/2016] [Indexed: 11/25/2022]
Affiliation(s)
- Yong Wang
- MOE Key Laboratory for Molecular Animal Nutrition, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Qinfang Zhu
- MOE Key Laboratory for Molecular Animal Nutrition, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Ling Huang
- MOE Key Laboratory for Molecular Animal Nutrition, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yanqing Zhu
- MOE Key Laboratory for Molecular Animal Nutrition, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Jun Chen
- College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Jinrong Peng
- MOE Key Laboratory for Molecular Animal Nutrition, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China
| | - Li Jan Lo
- MOE Key Laboratory for Molecular Animal Nutrition, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China.
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15
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Stępiński D. Nucleolus-derived mediators in oncogenic stress response and activation of p53-dependent pathways. Histochem Cell Biol 2016; 146:119-39. [PMID: 27142852 DOI: 10.1007/s00418-016-1443-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/25/2016] [Indexed: 12/12/2022]
Abstract
Rapid growth and division of cells, including tumor ones, is correlated with intensive protein biosynthesis. The output of nucleoli, organelles where translational machineries are formed, depends on a rate of particular stages of ribosome production and on accessibility of elements crucial for their effective functioning, including substrates, enzymes as well as energy resources. Different factors that induce cellular stress also often lead to nucleolar dysfunction which results in ribosome biogenesis impairment. Such nucleolar disorders, called nucleolar or ribosomal stress, usually affect cellular functioning which in fact is a result of p53-dependent pathway activation, elicited as a response to stress. These pathways direct cells to new destinations such as cell cycle arrest, damage repair, differentiation, autophagy, programmed cell death or aging. In the case of impaired nucleolar functioning, nucleolar and ribosomal proteins mediate activation of the p53 pathways. They are also triggered as a response to oncogenic factor overexpression to protect tissues and organs against extensive proliferation of abnormal cells. Intentional impairment of any step of ribosome biosynthesis which would direct the cells to these destinations could be a strategy used in anticancer therapy. This review presents current knowledge on a nucleolus, mainly in relation to cancer biology, which is an important and extremely sensitive element of the mechanism participating in cellular stress reaction mediating activation of the p53 pathways in order to counteract stress effects, especially cancer development.
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Affiliation(s)
- Dariusz Stępiński
- Department of Cytophysiology, Faculty of Biology and Environmental Protection, University of Łódź, Pomorska 141/143, 90-236, Łódź, Poland.
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16
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van Sluis M, van Vuuren C, McStay B. The Relationship Between Human Nucleolar Organizer Regions and Nucleoli, Probed by 3D-ImmunoFISH. Methods Mol Biol 2016; 1455:3-14. [PMID: 27576706 DOI: 10.1007/978-1-4939-3792-9_1] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
3D-immunoFISH is a valuable technique to compare the localization of DNA sequences and proteins in cells where three-dimensional structure has been preserved. As nucleoli contain a multitude of protein factors dedicated to ribosome biogenesis and form around specific chromosomal loci, 3D-immunoFISH is a particularly relevant technique for their study. In human cells, nucleoli form around transcriptionally active ribosomal gene (rDNA) arrays termed nucleolar organizer regions (NORs) positioned on the p-arms of each of the acrocentric chromosomes. Here, we provide a protocol for fixing and permeabilizing human cells grown on microscope slides such that nucleolar proteins can be visualized using antibodies and NORs visualized by DNA FISH. Antibodies against UBF recognize transcriptionally active rDNA/NORs and NOP52 antibodies provide a convenient way of visualizing the nucleolar volume. We describe a probe designed to visualize rDNA and introduce a probe comprised of NOR distal sequences, which can be used to identify or count individual NORs.
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Affiliation(s)
- Marjolein van Sluis
- Centre for Chromosome Biology, National University of Ireland, Bioscience Research Building, University Road, Galway, Ireland
| | - Chelly van Vuuren
- Centre for Chromosome Biology, National University of Ireland, Bioscience Research Building, University Road, Galway, Ireland
| | - Brian McStay
- Centre for Chromosome Biology, National University of Ireland, Bioscience Research Building, University Road, Galway, Ireland.
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17
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Sirri V, Jourdan N, Hernandez-Verdun D, Roussel P. Sharing the mitotic pre-ribosomal particles between daughter cells. J Cell Sci 2016; 129:1592-604. [DOI: 10.1242/jcs.180521] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Accepted: 02/20/2016] [Indexed: 01/05/2023] Open
Abstract
Ribosome biogenesis is a fundamental multistep process initiated by the synthesis of 90S pre-ribosomal particles in the nucleoli of higher eukaryotes. Even though synthesis of ribosomes stops during mitosis while nucleoli disappear, mitotic pre-ribosomal particles persist as observed in prenucleolar bodies (PNBs) during telophase. To further understand the relationship between the nucleolus and the PNBs, the presence and the fate of the mitotic pre-ribosomal particles during cell division was investigated. We demonstrate that the recently synthesized 45S precursor ribosomal RNAs (pre-rRNAs) but also the 32S and 30S pre-rRNAs are maintained during mitosis and associated with the chromosome periphery together with pre-rRNA processing factors. Maturation of the mitotic pre-ribosomal particles, as assessed by the stability of the mitotic pre-rRNAs, is transiently arrested during mitosis by a cyclin-dependent kinase (CDK)1-cyclin B-dependent mechanism and may be restored by CDK inhibitor treatments. At the M/G1 transition, the resumption of mitotic pre-rRNA processing in PNBs does not induce the disappearance of PNBs that only occurs when functional nucleoli reform. Strikingly, during their maturation process, mitotic pre-rRNAs localize in reforming nucleoli.
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Affiliation(s)
- Valentina Sirri
- Univ. Paris Diderot, Unit of Functional and Adaptive Biology, UMR 8251 CNRS, 4 rue Marie-Andrée Lagroua Weill-Hallé, F-75205 Paris, France
| | - Nathalie Jourdan
- UPMC Univ. Paris 06, Institut de Biologie Paris Seine, UMR 8256 CNRS, 9 quai St Bernard, F-75252 Paris, France
| | - Danièle Hernandez-Verdun
- Univ. Paris Diderot, Institut Jacques Monod, UMR 7592 CNRS, 15 rue Hélène Brion, F‑75205 Paris, France
| | - Pascal Roussel
- Univ. Paris Diderot, Unit of Functional and Adaptive Biology, UMR 8251 CNRS, 4 rue Marie-Andrée Lagroua Weill-Hallé, F-75205 Paris, France
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