1
|
Huo M, Rai SK, Nakatsu K, Deng Y, Jijiwa M. Subverting the Canon: Novel Cancer-Promoting Functions and Mechanisms for snoRNAs. Int J Mol Sci 2024; 25:2923. [PMID: 38474168 PMCID: PMC10932220 DOI: 10.3390/ijms25052923] [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: 01/18/2024] [Revised: 02/27/2024] [Accepted: 02/27/2024] [Indexed: 03/14/2024] Open
Abstract
Small nucleolar RNAs (snoRNAs) constitute a class of intron-derived non-coding RNAs ranging from 60 to 300 nucleotides. Canonically localized in the nucleolus, snoRNAs play a pivotal role in RNA modifications and pre-ribosomal RNA processing. Based on the types of modifications they involve, such as methylation and pseudouridylation, they are classified into two main families-box C/D and H/ACA snoRNAs. Recent investigations have revealed the unconventional synthesis and biogenesis strategies of snoRNAs, indicating their more profound roles in pathogenesis than previously envisioned. This review consolidates recent discoveries surrounding snoRNAs and provides insights into their mechanistic roles in cancer. It explores the intricate interactions of snoRNAs within signaling pathways and speculates on potential therapeutic solutions emerging from snoRNA research. In addition, it presents recent findings on the long non-coding small nucleolar RNA host gene (lncSNHG), a subset of long non-coding RNAs (lncRNAs), which are the transcripts of parental SNHGs that generate snoRNA. The nucleolus, the functional epicenter of snoRNAs, is also discussed. Through a deconstruction of the pathways driving snoRNA-induced oncogenesis, this review aims to serve as a roadmap to guide future research in the nuanced field of snoRNA-cancer interactions and inspire potential snoRNA-related cancer therapies.
Collapse
Affiliation(s)
- Matthew Huo
- Krieger School of Arts and Sciences, Johns Hopkins University, Baltimore, MD 21218, USA;
- Department of Quantitative Health Sciences, John A. Burns School of Medicine, University of Hawaii, Honolulu, HI 96813, USA; (S.K.R.); (K.N.)
| | - Sudhir Kumar Rai
- Department of Quantitative Health Sciences, John A. Burns School of Medicine, University of Hawaii, Honolulu, HI 96813, USA; (S.K.R.); (K.N.)
| | - Ken Nakatsu
- Department of Quantitative Health Sciences, John A. Burns School of Medicine, University of Hawaii, Honolulu, HI 96813, USA; (S.K.R.); (K.N.)
- Emory College of Arts and Sciences, Emory University, Atlanta, GA 30322, USA
| | - Youping Deng
- Department of Quantitative Health Sciences, John A. Burns School of Medicine, University of Hawaii, Honolulu, HI 96813, USA; (S.K.R.); (K.N.)
| | - Mayumi Jijiwa
- Department of Quantitative Health Sciences, John A. Burns School of Medicine, University of Hawaii, Honolulu, HI 96813, USA; (S.K.R.); (K.N.)
| |
Collapse
|
2
|
Qin J, Garus A, Autexier C. The C-terminal extension of dyskerin is a dyskeratosis congenita mutational hotspot that modulates interaction with telomerase RNA and subcellular localization. Hum Mol Genet 2024; 33:318-332. [PMID: 37879098 PMCID: PMC10840380 DOI: 10.1093/hmg/ddad180] [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: 08/24/2023] [Revised: 10/09/2023] [Accepted: 10/20/2023] [Indexed: 10/27/2023] Open
Abstract
Dyskerin is a component of the human telomerase complex and is involved in stabilizing the human telomerase RNA (hTR). Many mutations in the DKC1 gene encoding dyskerin are found in X-linked dyskeratosis congenita (X-DC), a premature aging disorder and other related diseases. The C-terminal extension (CTE) of dyskerin contributes to its interaction with the molecular chaperone SHQ1 during the early stage of telomerase biogenesis. Disease mutations in this region were proposed to disrupt dyskerin-SHQ1 interaction and destabilize dyskerin, reducing hTR levels indirectly. However, biochemical evidence supporting this hypothesis is still lacking. In addition, the effects of many CTE disease mutations on hTR have not been examined. In this study, we tested eight dyskerin CTE variants and showed that they failed to maintain hTR levels. These mutants showed slightly reduced but not abolished interaction with SHQ1, and caused defective binding to hTR. Deletion of the CTE further reduced binding to hTR, and perturbed localization of dyskerin to the Cajal bodies and the nucleolus, and the interaction with TCAB1 as well as GAR1. Our findings suggest impaired dyskerin-hTR interaction in cells as a previously overlooked mechanism through which dyskerin CTE mutations cause X-DC and related telomere syndromes.
Collapse
Affiliation(s)
- Jian Qin
- Department of Anatomy and Cell Biology, McGill University, 3640 University Street, Montreal, Quebec, QC H3A 0C7, Canada
- Lady Davis Institute, Jewish General Hospital, 3755 Chem, de la Côte-Sainte-Catherine, Montréal, QC H3T 1E2, Canada
| | - Alexandre Garus
- Department of Anatomy and Cell Biology, McGill University, 3640 University Street, Montreal, Quebec, QC H3A 0C7, Canada
- Lady Davis Institute, Jewish General Hospital, 3755 Chem, de la Côte-Sainte-Catherine, Montréal, QC H3T 1E2, Canada
| | - Chantal Autexier
- Department of Anatomy and Cell Biology, McGill University, 3640 University Street, Montreal, Quebec, QC H3A 0C7, Canada
- Lady Davis Institute, Jewish General Hospital, 3755 Chem, de la Côte-Sainte-Catherine, Montréal, QC H3T 1E2, Canada
| |
Collapse
|
3
|
Ghanim GE, Sekne Z, Balch S, van Roon AMM, Nguyen THD. 2.7 Å cryo-EM structure of human telomerase H/ACA ribonucleoprotein. Nat Commun 2024; 15:746. [PMID: 38272871 PMCID: PMC10811338 DOI: 10.1038/s41467-024-45002-x] [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: 06/27/2023] [Accepted: 01/03/2024] [Indexed: 01/27/2024] Open
Abstract
Telomerase is a ribonucleoprotein (RNP) enzyme that extends telomeric repeats at eukaryotic chromosome ends to counterbalance telomere loss caused by incomplete genome replication. Human telomerase is comprised of two distinct functional lobes tethered by telomerase RNA (hTR): a catalytic core, responsible for DNA extension; and a Hinge and ACA (H/ACA) box RNP, responsible for telomerase biogenesis. H/ACA RNPs also have a general role in pseudouridylation of spliceosomal and ribosomal RNAs, which is critical for the biogenesis of the spliceosome and ribosome. Much of our structural understanding of eukaryotic H/ACA RNPs comes from structures of the human telomerase H/ACA RNP. Here we report a 2.7 Å cryo-electron microscopy structure of the telomerase H/ACA RNP. The significant improvement in resolution over previous 3.3 Å to 8.2 Å structures allows us to uncover new molecular interactions within the H/ACA RNP. Many disease mutations are mapped to these interaction sites. The structure also reveals unprecedented insights into a region critical for pseudouridylation in canonical H/ACA RNPs. Together, our work advances understanding of telomerase-related disease mutations and the mechanism of pseudouridylation by eukaryotic H/ACA RNPs.
Collapse
Affiliation(s)
| | - Zala Sekne
- MRC Laboratory of Molecular Biology, Cambridge, CB2 0QH, UK
| | | | | | | |
Collapse
|
4
|
Alidou-D'Anjou I, Patel A, Sleiman S, Dragon F. Human SHQ1 variants R335C and A426V lead to severe ribosome biogenesis defects when expressed in yeast. Front Genet 2023; 14:1240416. [PMID: 37818102 PMCID: PMC10560722 DOI: 10.3389/fgene.2023.1240416] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Accepted: 08/17/2023] [Indexed: 10/12/2023] Open
Abstract
SHQ1 is an essential chaperone that binds the pseudouridine synthase dyskerin in the cytoplasm and escorts the enzyme to the nucleus, where dyskerin is assembled into small nucleolar RNPs (snoRNPs) of the H/ACA class. These particles carry out pseudouridine formation in ribosomal RNAs (rRNAs) and participate in maturation of rRNA precursors (pre-rRNAs). Variants of human SHQ1 have been linked to neurodevelopmental deficiencies; here we focused on two compound heterozygous mutations identified in a child showing a severe neurological disorder comprising cerebellar degeneration. To investigate the molecular defects caused by mutations R335C and A426V we used a conditional yeast strain that can be depleted of the endogenous Shq1 protein while constitutively expressing human SHQ1 (wild-type or variants). Although wild-type SHQ1 complemented the Shq1-depleted strain, cells expressing variant R335C could not support growth, and cells expressing variant A426V were temperature-sensitive. When shifted to restrictive conditions, yeast cells progressively lost H/ACA snoRNAs and accumulated unprocessed pre-rRNAs, which led to reduced production of ribosomes. Levels of Cbf5 (yeast homologue of dyskerin) were decreased in yeast cells expressing SHQ1 variants under restrictive conditions. Immunoprecipitation experiments revealed that interaction of Cbf5 with SHQ1 variants was weakened but not abolished, and yeast two-hybrid assays showed that mutation R335C is more deleterious than mutation A426V. Our data provide additional evidence for the critical role of SHQ1 in chaperoning the pseudouridine synthase dyskerin, and how its inadequate function has detrimental consequences on the production of H/ACA snoRNPs and ribosomes.
Collapse
Affiliation(s)
- Ismaël Alidou-D'Anjou
- Centre d'Excellence en Recherche sur les Maladies Orphelines-Fondation Courtois (CERMO-FC), Départment des Sciences Biologiques, Université du Québec à Montréal, Montréal, QC, Canada
| | - Aniket Patel
- Centre d'Excellence en Recherche sur les Maladies Orphelines-Fondation Courtois (CERMO-FC), Départment des Sciences Biologiques, Université du Québec à Montréal, Montréal, QC, Canada
| | - Sophie Sleiman
- Centre d'Excellence en Recherche sur les Maladies Orphelines-Fondation Courtois (CERMO-FC), Départment des Sciences Biologiques, Université du Québec à Montréal, Montréal, QC, Canada
| | - François Dragon
- Centre d'Excellence en Recherche sur les Maladies Orphelines-Fondation Courtois (CERMO-FC), Départment des Sciences Biologiques, Université du Québec à Montréal, Montréal, QC, Canada
| |
Collapse
|
5
|
AlHargan A, AlMuhaizea MA, Almass R, Alwadei AH, Daghestani M, Arold ST, Kaya N. SHQ1-associated neurodevelopmental disorder: Report of the first homozygous variant in unrelated patients and review of the literature. Hum Genome Var 2023; 10:7. [PMID: 36810590 PMCID: PMC9944922 DOI: 10.1038/s41439-023-00234-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 11/21/2022] [Accepted: 12/13/2022] [Indexed: 02/24/2023] Open
Abstract
Compound heterozygous mutations in SHQ1 have been associated with a rare and severe neurological disorder characterized by global developmental delay (GDD), cerebellar degeneration coupled with seizures, and early-onset dystonia. Currently, only five affected individuals have been documented in the literature. Here, we report three children from two unrelated families harboring a homozygous variant in the gene but with a milder phenotype than previously described. The patients had GDD and seizures. Magnetic resonance imaging analyses revealed diffuse white matter hypomyelination. Sanger sequencing confirmed the whole-exome sequencing results and revealed full segregation of the missense variant (SHQ1:c.833 T > C; p.I278T) in both families. We performed a comprehensive in silico analysis using different prediction classifiers and structural modeling of the variant. Our findings demonstrate that this novel homozygous variant in SHQ1 is likely to be pathogenic and leads to the clinical features observed in our patients.
Collapse
Affiliation(s)
- Aljouhra AlHargan
- Translational Genomics Department, MBC: 26, Center for Genomic Medicine, King Faisal Specialist Hospital and Research Centre (KFSHRC), Riyadh, 11211, Saudi Arabia
- Department of Zoology, P.O. Box. 145111, College of Sciences, King Saud University, Riyadh, 11362, Saudi Arabia
| | - Mohammed A AlMuhaizea
- Neuroscience Centre, MBC: 76, King Faisal Specialist Hospital and Research Centre, Riyadh, 11211, Saudi Arabia
- College of Medicine, AlFaisal University, Riyadh, Saudi Arabia
| | - Rawan Almass
- Department of Medical Genomics, MBC: 75, Center for Genomic Medicine, King Faisal Specialist Hospital and Research Centre, Riyadh, 11211, Saudi Arabia
| | - Ali H Alwadei
- Pediatric Neurology Department, National Neuroscience Institute, King Fahad Medical City, Riyadh, Saudi Arabia
| | - Maha Daghestani
- Department of Zoology, P.O. Box. 145111, College of Sciences, King Saud University, Riyadh, 11362, Saudi Arabia
| | - Stefan T Arold
- Bioscience Program, Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Kingdom of Saudi Arabia
- Computational Biology Research Center, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
- Centre de Biologie Structurale (CBS), INSERM, CNRS, Université de Montpellier, F-34090, Montpellier, France
| | - Namik Kaya
- Translational Genomics Department, MBC: 26, Center for Genomic Medicine, King Faisal Specialist Hospital and Research Centre (KFSHRC), Riyadh, 11211, Saudi Arabia.
| |
Collapse
|
6
|
Webster SF, Ghalei H. Maturation of small nucleolar RNAs: from production to function. RNA Biol 2023; 20:715-736. [PMID: 37796118 PMCID: PMC10557570 DOI: 10.1080/15476286.2023.2254540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/28/2023] [Indexed: 10/06/2023] Open
Abstract
Small Nucleolar RNAs (snoRNAs) are an abundant group of non-coding RNAs with well-defined roles in ribosomal RNA processing, folding and chemical modification. Besides their classic roles in ribosome biogenesis, snoRNAs are also implicated in several other cellular activities including regulation of splicing, transcription, RNA editing, cellular trafficking, and miRNA-like functions. Mature snoRNAs must undergo a series of processing steps tightly regulated by transiently associating factors and coordinated with other cellular processes including transcription and splicing. In addition to their mature forms, snoRNAs can contribute to gene expression regulation through their derivatives and degradation products. Here, we review the current knowledge on mechanisms of snoRNA maturation, including the different pathways of processing, and the regulatory mechanisms that control snoRNA levels and complex assembly. We also discuss the significance of studying snoRNA maturation, highlight the gaps in the current knowledge and suggest directions for future research in this area.
Collapse
Affiliation(s)
- Sarah F. Webster
- Biochemistry, Cell, and Developmental Biology Graduate Program, Emory University, Atlanta, Georgia, USA
- Department of Biochemistry, Emory University, Atlanta, Georgia, USA
| | - Homa Ghalei
- Department of Biochemistry, Emory University, Atlanta, Georgia, USA
| |
Collapse
|
7
|
Garus A, Autexier C. Dyskerin: an essential pseudouridine synthase with multifaceted roles in ribosome biogenesis, splicing, and telomere maintenance. RNA (NEW YORK, N.Y.) 2021; 27:1441-1458. [PMID: 34556550 PMCID: PMC8594475 DOI: 10.1261/rna.078953.121] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Dyskerin and its homologs are ancient and conserved enzymes that catalyze the most common post-transcriptional modification found in cells, pseudouridylation. The resulting pseudouridines provide stability to RNA molecules and regulate ribosome biogenesis and splicing events. Dyskerin does not act independently-it is the core component of a protein heterotetramer, which associates with RNAs that contain the H/ACA motif. The variety of H/ACA RNAs that guide the function of this ribonucleoprotein (RNP) complex highlights the diversity of cellular processes in which dyskerin participates. When associated with small nucleolar (sno) RNAs, it regulates ribosomal (r) RNAs and ribosome biogenesis. By interacting with small Cajal body (sca) RNAs, it targets small nuclear (sn) RNAs to regulate pre-mRNA splicing. As a component of the telomerase holoenzyme, dyskerin binds to the telomerase RNA to modulate telomere maintenance. In a disease context, dyskerin malfunction can result in multiple detrimental phenotypes. Mutations in DKC1, the gene that encodes dyskerin, cause the premature aging syndrome X-linked dyskeratosis congenita (X-DC), a still incurable disorder that typically leads to bone marrow failure. In this review, we present the classical and most recent findings on this essential protein, discussing the evolutionary, structural, and functional aspects of dyskerin and the H/ACA RNP. The latest research underscores the role that dyskerin plays in the regulation of gene expression, translation efficiency, and telomere maintenance, along with the impacts that defective dyskerin has on aging, cell proliferation, haematopoietic potential, and cancer.
Collapse
Affiliation(s)
- Alexandre Garus
- Department of Anatomy and Cell Biology, McGill University, Montreal, Quebec, H3A 0C7, Canada
- Jewish General Hospital, Lady Davis Institute, Montreal, Quebec, H3T 1E2, Canada
| | - Chantal Autexier
- Department of Anatomy and Cell Biology, McGill University, Montreal, Quebec, H3A 0C7, Canada
- Jewish General Hospital, Lady Davis Institute, Montreal, Quebec, H3T 1E2, Canada
| |
Collapse
|
8
|
SUMOylation- and GAR1-Dependent Regulation of Dyskerin Nuclear and Subnuclear Localization. Mol Cell Biol 2021; 41:MCB.00464-20. [PMID: 33526451 DOI: 10.1128/mcb.00464-20] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Accepted: 01/20/2021] [Indexed: 12/29/2022] Open
Abstract
The nuclear and subnuclear compartmentalization of the telomerase-associated protein and H/ACA ribonucleoprotein component dyskerin is an important although incompletely understood aspect of H/ACA ribonucleoprotein function. Four SUMOylation sites were previously identified in the C-terminal nuclear/nucleolar localization signal (N/NoLS) of dyskerin. We found that a cytoplasmic localized C-terminal truncation variant of dyskerin lacking most of the C-terminal N/NoLS represents an under-SUMOylated variant of dyskerin compared to wild-type dyskerin. We demonstrate that mimicking constitutive SUMOylation of dyskerin using a SUMO3 fusion construct can drive nuclear accumulation of this variant and that the SUMO site K467 in this N/NoLS is particularly important for the subnuclear localization of dyskerin to the nucleolus in a mature H/ACA complex assembly- and SUMO-dependent manner. We also characterize a novel SUMO-interacting motif in the mature H/ACA complex component GAR1 that mediates the interaction between dyskerin and GAR1. Mislocalization of dyskerin, either in the cytoplasm or excluded from the nucleolus, disrupts dyskerin function and leads to reduced interaction of dyskerin with the telomerase RNA. These data indicate a role for dyskerin C-terminal N/NoLS SUMOylation in regulating the nuclear and subnuclear localization of dyskerin, which is essential for dyskerin function as both a telomerase-associated protein and as an H/ACA ribonucleoprotein.
Collapse
|
9
|
Czekay DP, Kothe U. H/ACA Small Ribonucleoproteins: Structural and Functional Comparison Between Archaea and Eukaryotes. Front Microbiol 2021; 12:654370. [PMID: 33776984 PMCID: PMC7991803 DOI: 10.3389/fmicb.2021.654370] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Accepted: 02/18/2021] [Indexed: 01/04/2023] Open
Abstract
During ribosome synthesis, ribosomal RNA is modified through the formation of many pseudouridines and methylations which contribute to ribosome function across all domains of life. In archaea and eukaryotes, pseudouridylation of rRNA is catalyzed by H/ACA small ribonucleoproteins (sRNPs) utilizing different H/ACA guide RNAs to identify target uridines for modification. H/ACA sRNPs are conserved in archaea and eukaryotes, as they share a common general architecture and function, but there are also several notable differences between archaeal and eukaryotic H/ACA sRNPs. Due to the higher protein stability in archaea, we have more information on the structure of archaeal H/ACA sRNPs compared to eukaryotic counterparts. However, based on the long history of yeast genetic and other cellular studies, the biological role of H/ACA sRNPs during ribosome biogenesis is better understood in eukaryotes than archaea. Therefore, this review provides an overview of the current knowledge on H/ACA sRNPs from archaea, in particular their structure and function, and relates it to our understanding of the roles of eukaryotic H/ACA sRNP during eukaryotic ribosome synthesis and beyond. Based on this comparison of our current insights into archaeal and eukaryotic H/ACA sRNPs, we discuss what role archaeal H/ACA sRNPs may play in the formation of ribosomes.
Collapse
Affiliation(s)
- Dominic P Czekay
- Department of Chemistry and Biochemistry, Alberta RNA Research and Training Institute, University of Lethbridge, Lethbridge, AB, Canada
| | - Ute Kothe
- Department of Chemistry and Biochemistry, Alberta RNA Research and Training Institute, University of Lethbridge, Lethbridge, AB, Canada
| |
Collapse
|
10
|
Dsouza VL, Adiga D, Sriharikrishnaa S, Suresh PS, Chatterjee A, Kabekkodu SP. Small nucleolar RNA and its potential role in breast cancer - A comprehensive review. Biochim Biophys Acta Rev Cancer 2021; 1875:188501. [PMID: 33400969 DOI: 10.1016/j.bbcan.2020.188501] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 12/07/2020] [Accepted: 12/28/2020] [Indexed: 02/07/2023]
Abstract
Small Nucleolar RNAs (snoRNAs) are known for their canonical functions, including ribosome biogenesis and RNA modification. snoRNAs act as endogenous sponges that regulate miRNA expression. Thus, precise snoRNA expression is critical for fine-tuning miRNA expression. snoRNAs processed into miRNA-like sequences play a crucial role in regulating the expression of protein-coding genes similar to that of miRNAs. Recent studies have linked snoRNA deregulation to breast cancer (BC). Inappropriate snoRNA expression contributes to BC pathology by facilitating breast cells to acquire cancer hallmarks. Since snoRNAs show significant differential expression in normal and cancer conditions, measuring snoRNA levels could be useful for BC prognosis and diagnosis. The present article provides a comprehensive overview of the role of snoRNAs in breast cancer pathology. More specifically, we have discussed the regulation, biological function, signaling pathways, and clinical utility of abnormally expressed snoRNAs in BC. Besides, we have also discussed the role of snoRNA host genes in breast tumorigenesis and emerging and future research directions in the field of snoRNA and cancer.
Collapse
Affiliation(s)
- Venzil Lavie Dsouza
- Department of Cell and Molecular Biology, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India
| | - Divya Adiga
- Department of Cell and Molecular Biology, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India
| | - S Sriharikrishnaa
- Department of Cell and Molecular Biology, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India
| | - Padmanaban S Suresh
- School of Biotechnology, National Institute of Technology, Calicut, Kerala 673601, India
| | - Aniruddha Chatterjee
- Department of Pathology, Otago Medical School, Dunedin Campus, University of Otago, Dunedin, New Zealand
| | - Shama Prasada Kabekkodu
- Department of Cell and Molecular Biology, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India.
| |
Collapse
|
11
|
Jiang X, Xing L, Chen Y, Qin R, Song S, Lu Y, Xie S, Wang L, Pu H, Gui X, Li T, Xu J, Li J, Jia S, Lu D. CircMEG3 inhibits telomerase activity by reducing Cbf5 in human liver cancer stem cells. MOLECULAR THERAPY. NUCLEIC ACIDS 2020; 23:310-323. [PMID: 33425489 PMCID: PMC7779543 DOI: 10.1016/j.omtn.2020.11.009] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Accepted: 11/10/2020] [Indexed: 12/13/2022]
Abstract
Circular RNA (CircRNA) is a newly identified special class of non-coding RNA (ncRNA) that plays an important regulatory role in the progression of certain diseases. Herein, our results indicate that CircMEG3 is downregulated expression and negatively correlated with the expression of telomerase-related gene Cbf5 in human liver cancer. Moreover, CircMEG3 inhibits the growth of human liver cancer stem cells in vivo and in vitro. CircMEG3 inhibits the expression of m6A methyltransferase METTL3 dependent on HULC. Moreover, CircMEG3 inhibits the expression of Cbf5, a component of telomere synthetase H/ACA ribonucleoprotein (RNP; catalyst RNA pseudouracil modification) through METTL3 dependent on HULC. Thereby, CircMEG3 inhibits telomerase activity and shortens telomere lifespan dependent on HULC and Cbf5 in human liver cancer stem cell. Strikingly, increased Cbf5 abrogates the ability of CircMEG3 to inhibit malignant differentiation of human liver cancer stem cells. In summary, these observations provide important basic information for finding effective liver cancer therapeutic targets.
Collapse
Affiliation(s)
- Xiaoxue Jiang
- Shanghai Putuo District People's Hospital, School of Life Science and Technology, Tongji University, Shanghai 200092, China
| | - Libo Xing
- Shanghai Putuo District People's Hospital, School of Life Science and Technology, Tongji University, Shanghai 200092, China
| | - Yingjie Chen
- Shanghai Putuo District People's Hospital, School of Life Science and Technology, Tongji University, Shanghai 200092, China
| | - Rushi Qin
- Shanghai Putuo District People's Hospital, School of Life Science and Technology, Tongji University, Shanghai 200092, China
| | - Shuting Song
- Shanghai Putuo District People's Hospital, School of Life Science and Technology, Tongji University, Shanghai 200092, China
| | - Yanan Lu
- Shanghai Putuo District People's Hospital, School of Life Science and Technology, Tongji University, Shanghai 200092, China
| | - Sijie Xie
- Shanghai Putuo District People's Hospital, School of Life Science and Technology, Tongji University, Shanghai 200092, China
| | - Liyan Wang
- Shanghai Putuo District People's Hospital, School of Life Science and Technology, Tongji University, Shanghai 200092, China
| | - Hu Pu
- Shanghai Putuo District People's Hospital, School of Life Science and Technology, Tongji University, Shanghai 200092, China
| | - Xin Gui
- Shanghai Putuo District People's Hospital, School of Life Science and Technology, Tongji University, Shanghai 200092, China
| | - Tianming Li
- Shanghai Putuo District People's Hospital, School of Life Science and Technology, Tongji University, Shanghai 200092, China
| | - Jie Xu
- School of Medicine, Tongji University, Shanghai 200092, China
| | - Jiao Li
- School of Medicine, Tongji University, Shanghai 200092, China
| | - Song Jia
- School of Medicine, Tongji University, Shanghai 200092, China
| | - Dongdong Lu
- Shanghai Putuo District People's Hospital, School of Life Science and Technology, Tongji University, Shanghai 200092, China
| |
Collapse
|
12
|
Wang Y, Sušac L, Feigon J. Structural Biology of Telomerase. Cold Spring Harb Perspect Biol 2019; 11:cshperspect.a032383. [PMID: 31451513 DOI: 10.1101/cshperspect.a032383] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Telomerase is a DNA polymerase that extends the 3' ends of chromosomes by processively synthesizing multiple telomeric repeats. It is a unique ribonucleoprotein (RNP) containing a specialized telomerase reverse transcriptase (TERT) and telomerase RNA (TER) with its own template and other elements required with TERT for activity (catalytic core), as well as species-specific TER-binding proteins important for biogenesis and assembly (core RNP); other proteins bind telomerase transiently or constitutively to allow association of telomerase and other proteins with telomere ends for regulation of DNA synthesis. Here we describe how nuclear magnetic resonance (NMR) spectroscopy and X-ray crystallography of TER and protein domains helped define the structure and function of the core RNP, laying the groundwork for interpreting negative-stain and cryo electron microscopy (cryo-EM) density maps of Tetrahymena thermophila and human telomerase holoenzymes. As the resolution has improved from ∼30 Å to ∼5 Å, these studies have provided increasingly detailed information on telomerase architecture and mechanism.
Collapse
Affiliation(s)
- Yaqiang Wang
- Department of Chemistry and Biochemistry, University of California Los Angeles (UCLA), Los Angeles, California 90095-1569
| | - Lukas Sušac
- Department of Chemistry and Biochemistry, University of California Los Angeles (UCLA), Los Angeles, California 90095-1569
| | - Juli Feigon
- Department of Chemistry and Biochemistry, University of California Los Angeles (UCLA), Los Angeles, California 90095-1569
| |
Collapse
|
13
|
Zhang D, Zhou J, Gao J, Wu RY, Huang YL, Jin QW, Chen JS, Tang WZ, Yan LH. Targeting snoRNAs as an emerging method of therapeutic development for cancer. Am J Cancer Res 2019; 9:1504-1516. [PMID: 31497339 PMCID: PMC6726984] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Accepted: 05/18/2019] [Indexed: 06/10/2023] Open
Abstract
The relevance of the dysregulation of snoRNAs in human cancer has been widely investigated and has challenged the view that snoRNAs merely function as house-keeping genes for the posttranscriptional modification of rRNAs. Accumulating evidence has shown the intimate connection between snoRNAs and proliferation, apoptosis, invasion and migration of tumor cells via manual intervention patterns of snoRNA expression. In this review, we focused on how snoRNAs are dysregulated and its regulation of the formation and development of cancer. We summarized the non-classical functions of snoRNAs in the context of their regulations of the signaling pathways involving PI3K-AKT and K-Ras and p53-dependant manner. Under these novel functions and characteristics, snoRNAs can act as potential and feasible biomarkers for diagnosis. Simultaneously, these promising therapeutic strategies should be considered to counteract the perturbations of snoRNAs.
Collapse
Affiliation(s)
- Di Zhang
- Department of Gastrointestinal Surgery, Affiliated Tumor Hospital of Guangxi Medical UniversityNanning 530021, Guangxi Zhuang Autonomous Region, China
- Guangxi Clinical Research Center for Colorectal CancerNanning 530021, Guangxi Zhuang Autonomous Region, China
| | - Juan Zhou
- Department of Gynecological Surgery, Affiliated Tumor Hospital of Guangxi Medical UniversityNanning 530021, Guangxi Zhuang Autonomous Region, China
| | - Jie Gao
- Department of Gastrointestinal Surgery, Affiliated Tumor Hospital of Guangxi Medical UniversityNanning 530021, Guangxi Zhuang Autonomous Region, China
- Guangxi Clinical Research Center for Colorectal CancerNanning 530021, Guangxi Zhuang Autonomous Region, China
| | - Ri-Ying Wu
- Department of Gastrointestinal Surgery, Affiliated Tumor Hospital of Guangxi Medical UniversityNanning 530021, Guangxi Zhuang Autonomous Region, China
- Guangxi Clinical Research Center for Colorectal CancerNanning 530021, Guangxi Zhuang Autonomous Region, China
| | - Ying-Long Huang
- Department of Gastrointestinal Surgery, Affiliated Tumor Hospital of Guangxi Medical UniversityNanning 530021, Guangxi Zhuang Autonomous Region, China
- Guangxi Clinical Research Center for Colorectal CancerNanning 530021, Guangxi Zhuang Autonomous Region, China
| | - Qin-Wen Jin
- Department of Gastrointestinal Surgery, Affiliated Tumor Hospital of Guangxi Medical UniversityNanning 530021, Guangxi Zhuang Autonomous Region, China
- Guangxi Clinical Research Center for Colorectal CancerNanning 530021, Guangxi Zhuang Autonomous Region, China
| | - Jian-Si Chen
- Department of Gastrointestinal Surgery, Affiliated Tumor Hospital of Guangxi Medical UniversityNanning 530021, Guangxi Zhuang Autonomous Region, China
- Guangxi Clinical Research Center for Colorectal CancerNanning 530021, Guangxi Zhuang Autonomous Region, China
| | - Wei-Zhong Tang
- Department of Gastrointestinal Surgery, Affiliated Tumor Hospital of Guangxi Medical UniversityNanning 530021, Guangxi Zhuang Autonomous Region, China
- Guangxi Clinical Research Center for Colorectal CancerNanning 530021, Guangxi Zhuang Autonomous Region, China
| | - Lin-Hai Yan
- Department of Gastrointestinal Surgery, Affiliated Tumor Hospital of Guangxi Medical UniversityNanning 530021, Guangxi Zhuang Autonomous Region, China
- Guangxi Clinical Research Center for Colorectal CancerNanning 530021, Guangxi Zhuang Autonomous Region, China
| |
Collapse
|
14
|
Boivin V, Faucher-Giguère L, Scott M, Abou-Elela S. The cellular landscape of mid-size noncoding RNA. WILEY INTERDISCIPLINARY REVIEWS-RNA 2019; 10:e1530. [PMID: 30843375 PMCID: PMC6619189 DOI: 10.1002/wrna.1530] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Revised: 02/08/2019] [Accepted: 02/09/2019] [Indexed: 01/06/2023]
Abstract
Noncoding RNA plays an important role in all aspects of the cellular life cycle, from the very basic process of protein synthesis to specialized roles in cell development and differentiation. However, many noncoding RNAs remain uncharacterized and the function of most of them remains unknown. Mid-size noncoding RNAs (mncRNAs), which range in length from 50 to 400 nucleotides, have diverse regulatory functions but share many fundamental characteristics. Most mncRNAs are produced from independent promoters although others are produced from the introns of other genes. Many are found in multiple copies in genomes. mncRNAs are highly structured and carry many posttranscriptional modifications. Both of these facets dictate their RNA-binding protein partners and ultimately their function. mncRNAs have already been implicated in translation, catalysis, as guides for RNA modification, as spliceosome components and regulatory RNA. However, recent studies are adding new mncRNA functions including regulation of gene expression and alternative splicing. In this review, we describe the different classes, characteristics and emerging functions of mncRNAs and their relative expression patterns. Finally, we provide a portrait of the challenges facing their detection and annotation in databases. This article is categorized under: Regulatory RNAs/RNAi/Riboswitches > Regulatory RNAs RNA Structure and Dynamics > RNA Structure, Dynamics, and Chemistry RNA Structure and Dynamics > Influence of RNA Structure in Biological Systems RNA Evolution and Genomics > RNA and Ribonucleoprotein Evolution.
Collapse
Affiliation(s)
- Vincent Boivin
- Department of Biochemistry, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Laurence Faucher-Giguère
- Department of Microbiology and Infectious Disease, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Michelle Scott
- Department of Biochemistry, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Sherif Abou-Elela
- Department of Microbiology and Infectious Disease, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| |
Collapse
|
15
|
Viviescas MA, Cano MIN, Segatto M. Chaperones and Their Role in Telomerase Ribonucleoprotein Biogenesis and Telomere Maintenance. CURR PROTEOMICS 2018. [DOI: 10.2174/1570164615666180713103133] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Telomere length maintenance is important for genome stability and cell division. In most
eukaryotes, telomeres are maintained by the telomerase ribonucleoprotein (RNP) complex, minimally
composed of the Telomerase Reverse Transcriptase (TERT) and the telomerase RNA (TER) components.
In addition to TERT and TER, other protein subunits are part of the complex and are involved in
telomerase regulation, assembly, disassembly, and degradation. Among them are some molecular
chaperones such as Hsp90 and its co-chaperone p23 which are found associated with the telomerase
RNP complex in humans, yeast and probably in protozoa. Hsp90 and p23 are necessary for the telomerase
RNP assembly and enzyme activity. In budding yeast, the Hsp90 homolog (Hsp82) is also responsible
for the association and dissociation of telomerase from the telomeric DNA by its direct interaction
with a telomere end-binding protein (Cdc13), responsible for regulating telomerase access to telomeres.
In addition, AAA+ ATPases, such as Pontin and Reptin, which are also considered chaperone-
like proteins, associate with the human telomerase complex by the direct interaction of Pontin with
TERT and dyskerin. They are probably responsible for telomerase RNP assembly since their depletion
impairs the accumulation of the complex. Moreover, various RNA chaperones, are also pivotal in the
assembly and migration of the mature telomerase complex and complex intermediates. In this review,
we will focus on the importance of molecular chaperones for telomerase RNP biogenesis and how they
impact telomere length maintenance and cellular homeostasis.
Collapse
Affiliation(s)
- Maria Alejandra Viviescas
- Genetics Department, Biosciences Institute, Sao Paulo State University (UNESP), Botucatu, SP, Brazil
| | | | - Marcela Segatto
- Genetics Department, Biosciences Institute, Sao Paulo State University (UNESP), Botucatu, SP, Brazil
| |
Collapse
|
16
|
Homology Model and Docking-Based Virtual Screening for Ligands of Human Dyskerin as New Inhibitors of Telomerase for Cancer Treatment. Int J Mol Sci 2018; 19:ijms19103216. [PMID: 30340325 PMCID: PMC6214037 DOI: 10.3390/ijms19103216] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Revised: 10/06/2018] [Accepted: 10/08/2018] [Indexed: 01/31/2023] Open
Abstract
Immortality is one of the main features of cancer cells. Tumor cells have an unlimited replicative potential, principally due to the holoenzyme telomerase. Telomerase is composed mainly by dyskerin (DKC1), a catalytic retrotranscriptase (hTERT) and an RNA template (hTR). The aim of this work is to develop new inhibitors of telomerase, selecting the interaction between hTR⁻DKC1 as a target. We designed two models of the human protein DKC1: homology and ab initio. These models were evaluated by different procedures, revealing that the homology model parameters were the most accurate. We selected two hydrophobic pockets contained in the PUA (pseudouridine synthase and archaeosine transglycosylase) domain, using structural and stability analysis. We carried out a docking-based virtual screen on these pockets, using the reported mutation K314 as the center of the docking. The hDKC1 model was tested against a library of 450,000 drug-like molecules. We selected the first 10 molecules that showed the highest affinity values to test their inhibitory activity on the cell line MDA MB 231 (Monroe Dunaway Anderson Metastasis Breast cancer 231), obtaining three compounds that showed inhibitory effect. These results allowed us to validate our design and set the basis to continue with the study of telomerase inhibitors for cancer treatment.
Collapse
|
17
|
Li LX, Liao HZ, Jiang LX, Tan Q, Ye D, Zhang XQ. Arabidopsis thaliana NOP10 is required for gametophyte formation. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2018; 60:723-736. [PMID: 29578643 DOI: 10.1111/jipb.12652] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 03/22/2018] [Indexed: 05/19/2023]
Abstract
The female gametophyte is crucial for sexual reproduction of higher plants, yet little is known about the molecular mechanisms underlying its development. Here, we report that Arabidopsis thaliana NOP10 (AtNOP10) is required for female gametophyte formation. AtNOP10 was expressed predominantly in the seedling and reproductive tissues, including anthers, pollen grains, and ovules. Mutations in AtNOP10 interrupted mitosis of the functional megaspore during early development and prevented polar nuclear fusion in the embryo sacs. AtNOP10 shares a high level of amino acid sequence similarity with Saccharomyces cerevisiae (yeast) NOP10 (ScNOP10), an important component of the H/ACA small nucleolar ribonucleoprotein particles (H/ACA snoRNPs) implicated in 18S rRNA synthesis and rRNA pseudouridylation. Heterologous expression of ScNOP10 complemented the mutant phenotype of Atnop10. Thus, AtNOP10 influences functional megaspore mitosis and polar nuclear fusion during gametophyte formation in Arabidopsis.
Collapse
Affiliation(s)
- Lin-Xiao Li
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Hong-Ze Liao
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
- State Key Laboratory of Non-Food Biomass Energy and Enzyme Technology, National Engineering Research Center for Non-Food Biorefinery and Guangxi Key Laboratory of Biorefinery, Guangxi Academy of Sciences, Nanning 530007, China
| | - Li-Xi Jiang
- College of Agriculture & Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Qing Tan
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - De Ye
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Xue-Qin Zhang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| |
Collapse
|
18
|
Bioinformatics Analysis of Genes and Pathways of CD11b +/Ly6C intermediate Macrophages after Renal Ischemia-Reperfusion Injury. Curr Med Sci 2018; 38:70-77. [PMID: 30074154 PMCID: PMC7089064 DOI: 10.1007/s11596-018-1848-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2017] [Revised: 11/08/2017] [Indexed: 12/12/2022]
Abstract
Renal ischemia-reperfusion injury (IRI) is a major cause of acute kidney injury (AKI), which could induce the poor prognosis. The purpose of this study was to characterize the molecular mechanism of the functional changes of CDllb+/Ly6Cintermediate macrophages after renal IRI. The gene expression profiles of CDllb+/Ly6Cintermcdiate macrophages of the sham surgery mice, and the mice 4 h, 24 h and 9 days after renal IRI were downloaded from the Gene Expression Omnibus database. Analysis of mRNA expression profiles was conducted to identify differentially expressed genes (DEGs), biological processes and pathways by the series test of cluster. Protein-protein interaction network was constructed and analysed to discover the key genes. A total of 6738 DEGs were identified and assigned to 20 model profiles. DEGs in profile 13 were one of the predominant expression profiles, which are involved in immune cell chemotaxis and proliferation. Signet analysis showed that Atp5al, Atp5o, Cox4i, Cdc42, Rac2 and Nhp2 were the key genes involved in oxidation-reduction, apoptosis, migration, M1-M2 differentiation, and proliferation of macrophages. RPS18 may be an appreciate reference gene as it was stable in macrophages. The identified DEGs and their enriched pathways investigate factors that may participate in the functional changes of CD 1lb+Ly6Cintermediate macrophages after renal IRI. Moreover, the vital gene Nhp2 may involve the polarization of macrophages, which may be a new target to affect the process of AKI
Collapse
|
19
|
Bizarro J, Meier UT. Inherited SHQ1 mutations impair interaction with NAP57/dyskerin, a major target in dyskeratosis congenita. Mol Genet Genomic Med 2017; 5:805-808. [PMID: 29178645 PMCID: PMC5702568 DOI: 10.1002/mgg3.314] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 06/12/2017] [Accepted: 06/14/2017] [Indexed: 01/28/2023] Open
Abstract
BACKGROUND The inherited bone marrow failure syndrome dyskeratosis congenita (DC) is most frequently caused by mutations in DKC1 (MIM# 300126), the gene encoding NAP57 (aka dyskerin). The typically missense mutations modulate the interaction of NAP57 with its chaperone SHQ1, but no DC mutations have been identified in SHQ1 (MIM# 613663). Here, we report on two compound heterozygous mutations in SHQ1 in a patient with a severe neurological disorder including cerebellar degeneration. METHODS The SHQ1 mutations were identified by patient exome sequencing. The impact of the mutations was assessed in pulldown assays with recombinant NAP57. RESULTS The SHQ1 mutations were the only set of mutations consistent with an autosomal recessive mode of inheritance. The mutations map to the SHQ1-NAP57 interface and impair the interaction of the recombinant SHQ1 variants with NAP57. CONCLUSION Intrauterine growth retardation and the neurological phenotype of the patient are reminiscent of the severe clinical variant of DC, the Hoyeraal-Hreidarsson syndrome (HH). Hence, SHQ1 screening may be warranted in patients with inherited bone marrow failure syndromes.
Collapse
Affiliation(s)
- Jonathan Bizarro
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York, 10461
| | - U Thomas Meier
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York, 10461
| |
Collapse
|
20
|
Cao T, Rajasingh S, Samanta S, Dawn B, Bittel DC, Rajasingh J. Biology and clinical relevance of noncoding sno/scaRNAs. Trends Cardiovasc Med 2017; 28:81-90. [PMID: 28869095 DOI: 10.1016/j.tcm.2017.08.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Revised: 07/18/2017] [Accepted: 08/04/2017] [Indexed: 12/15/2022]
Abstract
Small nucleolar RNAs (snoRNAs) are a group of noncoding RNAs that perform various biological functions, including biochemical modifications of other RNAs, precursors of miRNA, splicing, and telomerase activity. The small Cajal body-associated RNAs (scaRNAs) are a subset of the snoRNA family and collect in the Cajal body where they perform their canonical function to biochemically modify spliceosomal RNAs prior to maturation. Failure of sno/scaRNAs have been implicated in pathology such as congenital heart anomalies, neuromuscular disorders, and various malignancies. Thus, understanding of sno/scaRNAs demonstrates the clinical value.
Collapse
Affiliation(s)
- Thuy Cao
- Division of Cardiovascular Diseases, Department of Internal Medicine, Cardiovascular Research Institute, Kansas City, KS
| | - Sheeja Rajasingh
- Division of Cardiovascular Diseases, Department of Internal Medicine, Cardiovascular Research Institute, Kansas City, KS
| | - Saheli Samanta
- Division of Cardiovascular Diseases, Department of Internal Medicine, Cardiovascular Research Institute, Kansas City, KS
| | - Buddhadeb Dawn
- Division of Cardiovascular Diseases, Department of Internal Medicine, Cardiovascular Research Institute, Kansas City, KS
| | | | - Johnson Rajasingh
- Division of Cardiovascular Diseases, Department of Internal Medicine, Cardiovascular Research Institute, Kansas City, KS; Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS.
| |
Collapse
|
21
|
Massenet S, Bertrand E, Verheggen C. Assembly and trafficking of box C/D and H/ACA snoRNPs. RNA Biol 2017; 14:680-692. [PMID: 27715451 PMCID: PMC5519232 DOI: 10.1080/15476286.2016.1243646] [Citation(s) in RCA: 110] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Revised: 09/09/2016] [Accepted: 09/27/2016] [Indexed: 12/23/2022] Open
Abstract
Box C/D and box H/ACA snoRNAs are abundant non-coding RNAs that localize in the nucleolus and mostly function as guides for nucleotide modifications. While a large pool of snoRNAs modifies rRNAs, an increasing number of snoRNAs could also potentially target mRNAs. ScaRNAs belong to a family of specific RNAs that localize in Cajal bodies and that are structurally similar to snoRNAs. Most scaRNAs are involved in snRNA modification, while telomerase RNA, which contains H/ACA motifs, functions in telomeric DNA synthesis. In this review, we describe how box C/D and H/ACA snoRNAs are processed and assembled with core proteins to form functional RNP particles. Their biogenesis involve several transport factors that first direct pre-snoRNPs to Cajal bodies, where some processing steps are believed to take place, and then to nucleoli. Assembly of core proteins involves the HSP90/R2TP chaperone-cochaperone system for both box C/D and H/ACA RNAs, but also several factors specific for each family. These assembly factors chaperone unassembled core proteins, regulate the formation and disassembly of pre-snoRNP intermediates, and control the activity of immature particles. The AAA+ ATPase RUVBL1 and RUVBL2 belong to the R2TP co-chaperones and play essential roles in snoRNP biogenesis, as well as in the formation of other macro-molecular complexes. Despite intensive research, their mechanisms of action are still incompletely understood.
Collapse
Affiliation(s)
- Séverine Massenet
- Ingénierie Moléculaire et Physiopathologie Articulaire, UMR 7365 CNRS, 9 Avenue de la forêt de Haye, 54505 Vandoeuvre-les-Nancy Cedex, France, Université de Lorraine, Campus Biologie –Santé, CS 50184, 54505 Vandoeuvre-les-Nancy Cedex, France
| | - Edouard Bertrand
- Institut de Génétique Moléculaire de Montpellier, UMR 5535 CNRS, 1919 route de Mende, 34293 Montpellier cedex 5, France, Université de Montpellier, 163 rue Auguste Broussonnet, 34090 Montpellier, France
| | - Céline Verheggen
- Institut de Génétique Moléculaire de Montpellier, UMR 5535 CNRS, 1919 route de Mende, 34293 Montpellier cedex 5, France, Université de Montpellier, 163 rue Auguste Broussonnet, 34090 Montpellier, France
| |
Collapse
|
22
|
Abstract
Telomerase is an RNA-protein complex that extends the 3' ends of linear chromosomes, using a unique telomerase reverse transcriptase (TERT) and template in the telomerase RNA (TR), thereby helping to maintain genome integrity. TR assembles with TERT and species-specific proteins, and telomerase function in vivo requires interaction with telomere-associated proteins. Over the past two decades, structures of domains of TR and TERT as well as other telomerase- and telomere-interacting proteins have provided insights into telomerase function. A recently reported 9-Å cryo-electron microscopy map of the Tetrahymena telomerase holoenzyme has provided a framework for understanding how TR, TERT, and other proteins from ciliate as well as vertebrate telomerase fit and function together as well as unexpected insight into telomerase interaction at telomeres. Here we review progress in understanding the structural basis of human and Tetrahymena telomerase activity, assembly, and interactions.
Collapse
Affiliation(s)
- Henry Chan
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569; , ,
| | - Yaqiang Wang
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569; , ,
| | - Juli Feigon
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569; , ,
| |
Collapse
|
23
|
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.
Collapse
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
| |
Collapse
|
24
|
Ketele A, Kiss T, Jády BE. Human intron-encoded AluACA RNAs and telomerase RNA share a common element promoting RNA accumulation. RNA Biol 2016; 13:1274-1285. [PMID: 27726486 PMCID: PMC5207380 DOI: 10.1080/15476286.2016.1239689] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
Mammalian cells express hundreds of intron-encoded box H/ACA RNAs which fold into a common hairpin-hinge-hairpin-tail structure, interact with 4 evolutionarily conserved proteins, dyskerin, Nop10, Nhp2 and Gar1, and function mainly in RNA pseudouridylation. The human telomerase H/ACA RNA (hTR) directs telomeric DNA synthesis and it carries a 5'-terminal domain encompassing the telomeric template sequence. The primary hTR transcript is synthesized from an independent gene by RNA polymerase II and undergoes 3' end processing controlled by the 3'-terminal H/ACA domain. The apical stem-loop of the 3' hairpin of hTR carries a unique biogenesis-promoting element, the BIO motif that promotes hTR processing and RNP assembly. AluACA RNAs represent a distinct class of human H/ACA RNAs; they are processed from intronic Alu repetitive sequences. As compared to canonical H/ACA RNAs, the AluACA RNAs carry unusually short or long 5' hairpins and generally, they accumulate at low levels. Here, we demonstrate that the suboptimal 5' hairpins are responsible for the weak expression of AluACA RNAs. We also show that AluACA RNAs frequently carry a processing/stabilization element that is structurally and functionally indistinguishable from the hTR BIO motif. Both hTR and AluACA biogenesis-promoting elements are located in the terminal stem-loop of the 3'-terminal H/ACA hairpin, they show perfect structural conservation and are functionally interchangeable in in vivo RNA processing reactions. Our results demonstrate that the BIO motif, instead of being confined to hTR, is a more general H/ACA RNP biogenesis-facilitating element that can also promote processing/assembly of intron-encoded AluACA RNPs.
Collapse
Affiliation(s)
- Amandine Ketele
- a Laboratoire de Biologie Moléculaire Eucaryote du CNRS, UMR5099, Center de Biologie Intégrative, Université Paul Sabatier , Toulouse Cedex 9, France
| | - Tamás Kiss
- a Laboratoire de Biologie Moléculaire Eucaryote du CNRS, UMR5099, Center de Biologie Intégrative, Université Paul Sabatier , Toulouse Cedex 9, France.,b Biological Research Center, Hungarian Academy of Sciences , Szeged , Hungary
| | - Beáta E Jády
- a Laboratoire de Biologie Moléculaire Eucaryote du CNRS, UMR5099, Center de Biologie Intégrative, Université Paul Sabatier , Toulouse Cedex 9, France
| |
Collapse
|
25
|
MacNeil DE, Bensoussan HJ, Autexier C. Telomerase Regulation from Beginning to the End. Genes (Basel) 2016; 7:genes7090064. [PMID: 27649246 PMCID: PMC5042394 DOI: 10.3390/genes7090064] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Revised: 08/25/2016] [Accepted: 08/26/2016] [Indexed: 12/11/2022] Open
Abstract
The vast body of literature regarding human telomere maintenance is a true testament to the importance of understanding telomere regulation in both normal and diseased states. In this review, our goal was simple: tell the telomerase story from the biogenesis of its parts to its maturity as a complex and function at its site of action, emphasizing new developments and how they contribute to the foundational knowledge of telomerase and telomere biology.
Collapse
Affiliation(s)
- Deanna Elise MacNeil
- Bloomfield Centre for Research in Aging, Lady Davis Institute for Medical Research, Jewish General Hospital, 3755 Côte Ste-Catherine Road, Montréal, QC H3T 1E2, Canada.
- Room M-29, Department of Anatomy and Cell Biology, McGill University, 3640 University Street, Montréal, QC H3A 0C7, Canada.
| | - Hélène Jeanne Bensoussan
- Bloomfield Centre for Research in Aging, Lady Davis Institute for Medical Research, Jewish General Hospital, 3755 Côte Ste-Catherine Road, Montréal, QC H3T 1E2, Canada.
- Room M-29, Department of Anatomy and Cell Biology, McGill University, 3640 University Street, Montréal, QC H3A 0C7, Canada.
| | - Chantal Autexier
- Bloomfield Centre for Research in Aging, Lady Davis Institute for Medical Research, Jewish General Hospital, 3755 Côte Ste-Catherine Road, Montréal, QC H3T 1E2, Canada.
- Room M-29, Department of Anatomy and Cell Biology, McGill University, 3640 University Street, Montréal, QC H3A 0C7, Canada.
- Department of Experimental Medicine, McGill University, 1110 Pins Avenue West, Room 101, Montréal, QC H3A 1A3, Canada.
| |
Collapse
|
26
|
Poole AR, Enwerem II, Vicino IA, Coole JB, Smith SV, Hebert MD. Identification of processing elements and interactors implicate SMN, coilin and the pseudogene-encoded coilp1 in telomerase and box C/D scaRNP biogenesis. RNA Biol 2016; 13:955-972. [PMID: 27419845 DOI: 10.1080/15476286.2016.1211224] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Many cellular functions, such as translation, require ribonucleoproteins (RNPs). The biogenesis of RNPs is a multi-step process that, depending on the RNP, can take place in many cellular compartments. Here we examine 2 different RNPs: telomerase and small Cajal body-specific RNPs (scaRNPs). Both of these RNPs are enriched in the Cajal body (CB), which is a subnuclear domain that also has high concentrations of another RNP, small nuclear RNPs (snRNPs). SnRNPs are essential components of the spliceosome, and scaRNPs modify the snRNA component of the snRNP. The CB contains many proteins, including WRAP53, SMN and coilin, the CB marker protein. We show here that coilin, SMN and coilp1, a newly identified protein encoded by a pseudogene in human, associate with telomerase RNA and a subset of scaRNAs. We also have identified a processing element within box C/D scaRNA. Our findings thus further strengthen the connection between the CB proteins coilin and SMN in the biogenesis of telomeras e and box C/D scaRNPs, and reveal a new player, coilp1, that likely participates in this process.
Collapse
Affiliation(s)
- Aaron R Poole
- a Department of Biochemistry , The University of Mississippi Medical Center , Jackson , MS , USA
| | - Isioma I Enwerem
- a Department of Biochemistry , The University of Mississippi Medical Center , Jackson , MS , USA
| | - Ian A Vicino
- a Department of Biochemistry , The University of Mississippi Medical Center , Jackson , MS , USA
| | - Jackson B Coole
- a Department of Biochemistry , The University of Mississippi Medical Center , Jackson , MS , USA
| | - Stanley V Smith
- b Department of Pharmacology and Toxicology , The University of Mississippi Medical Center , Jackson , MS , USA
| | - Michael D Hebert
- a Department of Biochemistry , The University of Mississippi Medical Center , Jackson , MS , USA
| |
Collapse
|
27
|
Structure of GPN-Loop GTPase Npa3 and Implications for RNA Polymerase II Assembly. Mol Cell Biol 2015; 36:820-31. [PMID: 26711263 DOI: 10.1128/mcb.01009-15] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Accepted: 12/21/2015] [Indexed: 11/20/2022] Open
Abstract
Biogenesis of the 12-subunit RNA polymerase II (Pol II) transcription complex requires so-called GPN-loop GTPases, but the function of these enzymes is unknown. Here we report the first crystal structure of a eukaryotic GPN-loop GTPase, the Saccharomyces cerevisiae enzyme Npa3 (a homolog of human GPN1, also called RPAP4, XAB1, and MBDin), and analyze its catalytic mechanism. The enzyme was trapped in a GDP-bound closed conformation and in a novel GTP analog-bound open conformation displaying a conserved hydrophobic pocket distant from the active site. We show that Npa3 has chaperone activity and interacts with hydrophobic peptide regions of Pol II subunits that form interfaces in the assembled Pol II complex. Biochemical results are consistent with a model that the hydrophobic pocket binds peptides and that this can allosterically stimulate GTPase activity and subsequent peptide release. These results suggest that GPN-loop GTPases are assembly chaperones for Pol II and other protein complexes.
Collapse
|
28
|
Lin P, Mobasher ME, Hakakian Y, Kakarla V, Naseem AF, Ziai H, Alawi F. Differential requirements for H/ACA ribonucleoprotein components in cell proliferation and response to DNA damage. Histochem Cell Biol 2015; 144:543-58. [PMID: 26265134 DOI: 10.1007/s00418-015-1359-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/29/2015] [Indexed: 02/07/2023]
Abstract
H/ACA ribonucleoproteins (RNPs) are comprised of four conserved proteins, dyskerin, NHP2, NOP10, and GAR1, and a function-specifying, noncoding H/ACA RNA. H/ACA RNPs contribute to telomerase assembly and stabilization, and posttranscriptional processing of nascent ribosomal RNA and spliceosomal RNA. However, very little is known about the coordinated action of the four proteins in other biologic processes. As described herein, we observed a differential requirement for the proteins in cell proliferation and identified a possible reliance for these factors in regulation of specific DNA damage biomarkers. In particular, GAR1 expression was upregulated following exposure to all forms of genotoxic stress tested. In contrast, levels of the other proteins were either reduced or unaffected. Only GAR1 showed an altered subcellular localization with a shift from the nucleolus to the nucleoplasm after ultraviolet-C irradiation and doxorubicin treatments. Transient siRNA-mediated depletion of GAR1 and dyskerin arrested cell proliferation, whereas loss of either NHP2 or NOP10 had no effect. Finally, loss of dyskerin, GAR1, NHP2, and NOP10, respectively, limited the accumulation of DNA damage biomarkers. However, the individual responses were dependent upon the specific type of damage incurred. In general, loss of GAR1 had the most suppressive effect on the biomarkers tested. Since the specific responses to genotoxic stress, the contribution of each protein to cell proliferation, and the activation of DNA damage biomarkers were not equivalent, this suggests the possibility that at least some of the proteins, most notably GAR1, may potentially function independently of their respective roles within H/ACA RNP complexes.
Collapse
Affiliation(s)
- Ping Lin
- Department of Pathology, School of Dental Medicine, University of Pennsylvania, 240 South 40th Street, Levy Building - Room 328B, Philadelphia, PA, 19104, USA
| | - Maral E Mobasher
- Department of Pathology, School of Dental Medicine, University of Pennsylvania, 240 South 40th Street, Levy Building - Room 328B, Philadelphia, PA, 19104, USA
| | - Yasaman Hakakian
- Department of Pathology, School of Dental Medicine, University of Pennsylvania, 240 South 40th Street, Levy Building - Room 328B, Philadelphia, PA, 19104, USA
| | - Veena Kakarla
- Department of Pathology, School of Dental Medicine, University of Pennsylvania, 240 South 40th Street, Levy Building - Room 328B, Philadelphia, PA, 19104, USA
| | - Anum F Naseem
- Department of Pathology, School of Dental Medicine, University of Pennsylvania, 240 South 40th Street, Levy Building - Room 328B, Philadelphia, PA, 19104, USA
| | - Heliya Ziai
- Department of Pathology, School of Dental Medicine, University of Pennsylvania, 240 South 40th Street, Levy Building - Room 328B, Philadelphia, PA, 19104, USA
| | - Faizan Alawi
- Department of Pathology, School of Dental Medicine, University of Pennsylvania, 240 South 40th Street, Levy Building - Room 328B, Philadelphia, PA, 19104, USA.
| |
Collapse
|
29
|
Dupuis-Sandoval F, Poirier M, Scott MS. The emerging landscape of small nucleolar RNAs in cell biology. WILEY INTERDISCIPLINARY REVIEWS-RNA 2015; 6:381-97. [PMID: 25879954 PMCID: PMC4696412 DOI: 10.1002/wrna.1284] [Citation(s) in RCA: 155] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Revised: 03/18/2015] [Accepted: 03/20/2015] [Indexed: 01/07/2023]
Abstract
Small nucleolar RNAs (snoRNAs) are a large class of small noncoding RNAs present in all eukaryotes sequenced thus far. As a family, they have been well characterized as playing a central role in ribosome biogenesis, guiding either the sequence-specific chemical modification of pre-rRNA (ribosomal RNA) or its processing. However, in higher eukaryotes, numerous orphan snoRNAs were described over a decade ago, with no known target or ascribed function, suggesting the possibility of alternative cellular functionality. In recent years, thanks in great part to advances in sequencing methodologies, we have seen many examples of the diversity that exists in the snoRNA family on multiple levels. In this review, we discuss the identification of novel snoRNA members, of unexpected binding partners, as well as the clarification and extension of the snoRNA target space and the characterization of diverse new noncanonical functions, painting a new and extended picture of the snoRNA landscape. Under the deluge of novel features and functions that have recently come to light, snoRNAs emerge as a central, dynamic, and highly versatile group of small regulatory RNAs. WIREs RNA 2015, 6:381–397. doi: 10.1002/wrna.1284
Collapse
Affiliation(s)
- Fabien Dupuis-Sandoval
- Biochemistry Department, Faculty of Medicine and Health Sciences, University of Sherbrooke, Sherbrooke, Canada
| | - Mikaël Poirier
- Biochemistry Department, Faculty of Medicine and Health Sciences, University of Sherbrooke, Sherbrooke, Canada
| | - Michelle S Scott
- Biochemistry Department and RNA Group, Faculty of Medicine and Health Sciences, University of Sherbrooke, Sherbrooke, Canada
| |
Collapse
|
30
|
Lafontaine DLJ. Noncoding RNAs in eukaryotic ribosome biogenesis and function. Nat Struct Mol Biol 2015; 22:11-9. [PMID: 25565028 DOI: 10.1038/nsmb.2939] [Citation(s) in RCA: 174] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Accepted: 11/26/2014] [Indexed: 12/22/2022]
Abstract
The ribosome, central to protein synthesis in all cells, is a complex multicomponent assembly with rRNA at its functional core. During the process of ribosome biogenesis, diverse noncoding RNAs participate in controlling the quantity and quality of this rRNA. In this Review, I discuss the multiple roles assumed by noncoding RNAs during the different steps of ribosome biogenesis and how they contribute to the generation of ribosome heterogeneity, which affects normal and pathophysiological processes.
Collapse
Affiliation(s)
- Denis L J Lafontaine
- RNA Molecular Biology, Fonds National de la Recherche Scientifique, Université Libre de Bruxelles, Brussels, Belgium
| |
Collapse
|
31
|
Cerrudo CS, Mengual Gómez DL, Gómez DE, Ghiringhelli PD. Novel insights into the evolution and structural characterization of dyskerin using comprehensive bioinformatics analysis. J Proteome Res 2015; 14:874-87. [PMID: 25540932 DOI: 10.1021/pr500956k] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Dyskerin is a conserved nucleolar protein. Several related genetic diseases are caused by defects in dyskerin. We hypothesized that having a comprehensive bioinformatic analysis of dyskerin will help to develop new drugs for this diseases. We predicted protein domains and compared sequences and structures to detect the universe of dyskerin-like proteins. We identified conserved features of shared domains in the three superkingdoms. We analyzed the phylogenetic diversity, confirming that there is a strong structural conservation. Also, we studied the relationship of dyskerin-like proteins with other proteins through an integrative protein-protein interaction approach. Most of them are conserved among homologous eukaryotic and archaeal proteins. Our results highlighted the preservation of proteins interacting with dyskerin. We identified conserved dyskerin interactor proteins between the different eukaryotes organisms. Furthermore, we studied the existence of dyskerin-like proteins in different species. Also, we compared and analyzed the secondary structure with the hydrophobic profile, confirming that all have hydrophilic properties highly conserved among proteins. The greatest difference was observed in the NTE and CTE regions. Another aspect studied was the comparison and analysis of tertiary structures. In our knowledge, this is the first time that these analyses were performed in such a comprehensive manner.
Collapse
Affiliation(s)
- Carolina Susana Cerrudo
- Laboratory of Genetic Engineering and Cellular and Molecular Biology, Department of Science and Technology, Quilmes National University , Roque Saenz Peña 352, 1876 Bernal, Buenos Aires, Argentine
| | | | | | | |
Collapse
|
32
|
Singh M, Wang Z, Cascio D, Feigon J. Structure and interactions of the CS domain of human H/ACA RNP assembly protein Shq1. J Mol Biol 2014; 427:807-823. [PMID: 25553844 DOI: 10.1016/j.jmb.2014.12.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Revised: 12/13/2014] [Accepted: 12/16/2014] [Indexed: 12/27/2022]
Abstract
Shq1 is an essential protein involved in the early steps of biogenesis and assembly of H/ACA ribonucleoprotein particles (RNPs). Shq1 binds to dyskerin (Cbf5 in yeast) at an early step of H/ACA RNP assembly and is subsequently displaced by the H/ACA RNA. Shq1 contains an N-terminal CS and a C-terminal Shq1-specific domain (SSD). Dyskerin harbors many mutations associated with dyskeratosis congenita. Structures of yeast Shq1 SSD bound to Cbf5 revealed that only a subset of these mutations is in the SSD binding site, implicating another subset in the putative CS binding site. Here, we present the crystal structure of human Shq1 CS (hCS) and the nuclear magnetic resonance (NMR) and crystal structures of hCS containing a serine substitution for proline 22 that is associated with some prostate cancers. The structure of hCS is similar to yeast Shq1 CS domain (yCS) and consists of two β-sheets that form an immunoglobulin-like β-sandwich fold. The N-terminal affinity tag sequence AHHHHHH associates with a neighboring protein in the crystal lattice to form an extra β-strand. Deletion of this tag was required to get spectra suitable for NMR structure determination, while the tag was required for crystallization. NMR chemical shift perturbation (CSP) experiments with peptides derived from putative CS binding sites on dyskerin and Cbf5 revealed a conserved surface on CS important for Cbf5/dyskerin binding. A HADDOCK (high-ambiguity-driven protein-protein docking) model of a Shq1-Cbf5 complex that defines the position of CS domain in the pre-H/ACA RNP was calculated using the CSP data.
Collapse
Affiliation(s)
- Mahavir Singh
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095, USA
| | - Zhonghua Wang
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095, USA
| | - Duilio Cascio
- University of California Los Angeles-Department of Energy (UCLA-DOE) Institute for Genomics and Proteomics, University of California, Los Angeles, CA 90095, USA
| | - Juli Feigon
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095, USA; University of California Los Angeles-Department of Energy (UCLA-DOE) Institute for Genomics and Proteomics, University of California, Los Angeles, CA 90095, USA.
| |
Collapse
|
33
|
Bizarro J, Charron C, Boulon S, Westman B, Pradet-Balade B, Vandermoere F, Chagot ME, Hallais M, Ahmad Y, Leonhardt H, Lamond A, Manival X, Branlant C, Charpentier B, Verheggen C, Bertrand E. Proteomic and 3D structure analyses highlight the C/D box snoRNP assembly mechanism and its control. ACTA ACUST UNITED AC 2014; 207:463-80. [PMID: 25404746 PMCID: PMC4242836 DOI: 10.1083/jcb.201404160] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
During small nucleolar ribonucleoprotein complex assembly, a pre-snoRNP complex consisting only of protein components forms first, followed by displacement of the ZNHIT3 subunit when C/D snoRNAs bind and dynamic loading and unloading of RuvBL AAA+ ATPases. In vitro, assembly of box C/D small nucleolar ribonucleoproteins (snoRNPs) involves the sequential recruitment of core proteins to snoRNAs. In vivo, however, assembly factors are required (NUFIP, BCD1, and the HSP90–R2TP complex), and it is unknown whether a similar sequential scheme applies. In this paper, we describe systematic quantitative stable isotope labeling by amino acids in cell culture proteomic experiments and the crystal structure of the core protein Snu13p/15.5K bound to a fragment of the assembly factor Rsa1p/NUFIP. This revealed several unexpected features: (a) the existence of a protein-only pre-snoRNP complex containing five assembly factors and two core proteins, 15.5K and Nop58; (b) the characterization of ZNHIT3, which is present in the protein-only complex but gets released upon binding to C/D snoRNAs; (c) the dynamics of the R2TP complex, which appears to load/unload RuvBL AAA+ adenosine triphosphatase from pre-snoRNPs; and (d) a potential mechanism for preventing premature activation of snoRNP catalytic activity. These data provide a framework for understanding the assembly of box C/D snoRNPs.
Collapse
Affiliation(s)
- Jonathan Bizarro
- Equipe labellisée Ligue contre le Cancer, Centre National de la Recherche Scientifique Unité Mixte de Recherche 5535, Institut de Génétique Moléculaire de Montpellier, 34293 Montpellier, Cedex 5, France
| | - Christophe Charron
- Ingénierie Moléculaire et Physiopathologie Articulaire, Centre National de la Recherche Scientifique Unité Mixte de Recherche 7365, Université de Lorraine, Biopôle de l'Université de Lorraine, 54505 Vandoeuvre-les-Nancy Cedex, France
| | - Séverine Boulon
- Centre de Recherches de Biochimie Macromoléculaire, Unité Mixte de Recherche 5237, 34293 Montpellier, Cedex 5, France
| | - Belinda Westman
- Centre for Gene Regulation and Expression, University of Dundee, Dundee DD1 5EH, Scotland, UK
| | - Bérengère Pradet-Balade
- Equipe labellisée Ligue contre le Cancer, Centre National de la Recherche Scientifique Unité Mixte de Recherche 5535, Institut de Génétique Moléculaire de Montpellier, 34293 Montpellier, Cedex 5, France
| | - Franck Vandermoere
- Centre National de la Recherche Scientifique Unité Mixte de Recherche 5203, Institut de Génomique Fonctionnelle, F-34000 Montpellier, France Institut National de la Santé et de la Recherche Médicale, U661, F-34000 Montpellier, France Unité Mixte de Recherche 5203, Université de Montpellier 1 and Université de Montpellier 2, F-34000 Montpellier, France
| | - Marie-Eve Chagot
- Ingénierie Moléculaire et Physiopathologie Articulaire, Centre National de la Recherche Scientifique Unité Mixte de Recherche 7365, Université de Lorraine, Biopôle de l'Université de Lorraine, 54505 Vandoeuvre-les-Nancy Cedex, France
| | - Marie Hallais
- Equipe labellisée Ligue contre le Cancer, Centre National de la Recherche Scientifique Unité Mixte de Recherche 5535, Institut de Génétique Moléculaire de Montpellier, 34293 Montpellier, Cedex 5, France
| | - Yasmeen Ahmad
- Centre for Gene Regulation and Expression, University of Dundee, Dundee DD1 5EH, Scotland, UK
| | - Heinrich Leonhardt
- Munich Center for Integrated Protein Science (CiPS) and Department of Biology, Ludwig Maximilians University Munich, 82152 Planegg-Martinsried, Germany Munich Center for Integrated Protein Science (CiPS) and Department of Biology, Ludwig Maximilians University Munich, 82152 Planegg-Martinsried, Germany
| | - Angus Lamond
- Centre for Gene Regulation and Expression, University of Dundee, Dundee DD1 5EH, Scotland, UK
| | - Xavier Manival
- Ingénierie Moléculaire et Physiopathologie Articulaire, Centre National de la Recherche Scientifique Unité Mixte de Recherche 7365, Université de Lorraine, Biopôle de l'Université de Lorraine, 54505 Vandoeuvre-les-Nancy Cedex, France
| | - Christiane Branlant
- Ingénierie Moléculaire et Physiopathologie Articulaire, Centre National de la Recherche Scientifique Unité Mixte de Recherche 7365, Université de Lorraine, Biopôle de l'Université de Lorraine, 54505 Vandoeuvre-les-Nancy Cedex, France
| | - Bruno Charpentier
- Ingénierie Moléculaire et Physiopathologie Articulaire, Centre National de la Recherche Scientifique Unité Mixte de Recherche 7365, Université de Lorraine, Biopôle de l'Université de Lorraine, 54505 Vandoeuvre-les-Nancy Cedex, France
| | - Céline Verheggen
- Equipe labellisée Ligue contre le Cancer, Centre National de la Recherche Scientifique Unité Mixte de Recherche 5535, Institut de Génétique Moléculaire de Montpellier, 34293 Montpellier, Cedex 5, France
| | - Edouard Bertrand
- Equipe labellisée Ligue contre le Cancer, Centre National de la Recherche Scientifique Unité Mixte de Recherche 5535, Institut de Génétique Moléculaire de Montpellier, 34293 Montpellier, Cedex 5, France
| |
Collapse
|
34
|
Progress in structural studies of telomerase. Curr Opin Struct Biol 2014; 24:115-24. [PMID: 24508601 DOI: 10.1016/j.sbi.2014.01.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Revised: 01/01/2014] [Accepted: 01/08/2014] [Indexed: 02/01/2023]
Abstract
Telomerase is the ribonucleoprotein (RNP) reverse transcriptase responsible for synthesizing the 3' ends of linear chromosomes. It plays critical roles in tumorigenesis, cellular aging, and stem cell renewal. The past two years have seen exciting progress in determining telomerase holoenzyme architecture and the structural basis of telomerase activity. Notably, the first electron microscopy structures of telomerase were reported, of the Tetrahymena thermophila telomerase holoenzyme and a human telomerase dimer. In addition to new structures of TERT and TER domains, the first structures of telomerase protein domains beyond TERT, and their complexes with TER or telomeric single-stranded DNA, were reported. Together these studies provide the first glimpse into the organization of the proteins and RNA in the telomerase RNP.
Collapse
|
35
|
Yu YT, Meier UT. RNA-guided isomerization of uridine to pseudouridine--pseudouridylation. RNA Biol 2014; 11:1483-94. [PMID: 25590339 PMCID: PMC4615163 DOI: 10.4161/15476286.2014.972855] [Citation(s) in RCA: 92] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2014] [Accepted: 09/12/2014] [Indexed: 01/13/2023] Open
Abstract
Box H/ACA ribonucleoproteins (RNPs), each consisting of one unique guide RNA and 4 common core proteins, constitute a family of complex enzymes that catalyze, in an RNA-guided manner, the isomerization of uridines to pseudouridines (Ψs) in RNAs, a reaction known as pseudouridylation. Over the years, box H/ACA RNPs have been extensively studied revealing many important aspects of these RNA modifying machines. In this review, we focus on the composition, structure, and biogenesis of H/ACA RNPs. We explain the mechanism of how this enzyme family recognizes and specifies its target uridine in a substrate RNA. We discuss the substrates of box H/ACA RNPs, focusing on rRNA (rRNA) and spliceosomal small nuclear RNA (snRNA). We describe the modification product Ψ and its contribution to RNA function. Finally, we consider possible mechanisms of the bone marrow failure syndrome dyskeratosis congenita and of prostate and other cancers linked to mutations in H/ACA RNPs.
Collapse
Key Words
- DC, dyskeratosis congenita
- H/ACA
- HH, hoyeraal-hreidarsson syndrome
- PIKK, phosphatidylinositol 3-kinase-related kinase
- PUA, pseudouridylase and archaeosine transglycosylase
- RNA modification
- RNA-guided
- RNP, ribonucleoprotein
- SMN, survival of motor neuron protein
- SSD, SHQ1 specific domain
- U, uridine
- X-DC, X-linked dyskeratosis congenita
- dyskeratosis congenita
- prostate cancer
- pseudouridine
- rRNA
- rRNA, ribosomal RNA
- ribonucleoproteins
- sca, small Cajal body
- snRNA, small nuclear RNA
- sno, small nucleolar
- snoRNA
- snoRNA, small nucleolar RNA
- spliceosomal small nuclear RNA
- tRNA, transfer RNA
- ψ, pseudouridine, 5-ribosyluracil
Collapse
MESH Headings
- Dyskeratosis Congenita/genetics
- Dyskeratosis Congenita/metabolism
- Dyskeratosis Congenita/pathology
- Humans
- Isomerism
- Male
- Mutation
- Nucleic Acid Conformation
- Prostatic Neoplasms/genetics
- Prostatic Neoplasms/metabolism
- Prostatic Neoplasms/pathology
- Pseudouridine/metabolism
- RNA Processing, Post-Transcriptional
- RNA, Ribosomal/genetics
- RNA, Ribosomal/metabolism
- RNA, Small Nuclear/genetics
- RNA, Small Nuclear/metabolism
- RNA, Transfer, Amino Acid-Specific/genetics
- RNA, Transfer, Amino Acid-Specific/metabolism
- Ribonucleoproteins, Small Nuclear/genetics
- Ribonucleoproteins, Small Nuclear/metabolism
- Uridine/metabolism
- RNA, Guide, CRISPR-Cas Systems
Collapse
Affiliation(s)
- Yi-Tao Yu
- University of Rochester Medical Center; Department of Biochemistry and Biophysics; Center for RNA Biology; Rochester, NY USA
| | - U Thomas Meier
- Albert Einstein College of Medicine; Department of Anatomy and Structural Biology; Bronx, NY USA
| |
Collapse
|
36
|
Cerrudo CS, Ghiringhelli PD, Gomez DE. Protein universe containing a PUA RNA-binding domain. FEBS J 2013; 281:74-87. [PMID: 24393395 DOI: 10.1111/febs.12602] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2013] [Revised: 10/22/2013] [Accepted: 11/11/2013] [Indexed: 01/18/2023]
Abstract
Here, we review current knowledge about pseudouridine synthase and archaeosine transglycosylase (PUA)-domain-containing proteins to illustrate progress in this field. A methodological analysis of the literature about the topic was carried out, together with a 'qualitative comparative analysis' to give a more comprehensive review. Bioinformatics methods for whole-protein or protein-domain identification are commonly based on pairwise protein sequence comparisons; we added comparison of structures to detect the whole universe of proteins containing the PUA domain. We present an update of proteins having this domain, focusing on the specific proteins present in Homo sapiens (dyskerin, MCT1, Nip7, eIF2D and Nsun6), and explore the existence of these in other species. We also analyze the phylogenetic distribution of the PUA domain in different species and proteins. Finally, we performed a structural comparison of the PUA domain through data mining of structural databases, determining a conserved structural motif, despite the differences in the sequence, even among eukaryotes, archaea and bacteria. All data discussed in this review, both bibliographic and analytical, corroborate the functional importance of the PUA domain in RNA-binding proteins.
Collapse
Affiliation(s)
- Carolina S Cerrudo
- Laboratory of Genetic Engineering and Cellular and Molecular Biology, Quilmes National University, Bernal, Buenos Aires, Argentina
| | | | | |
Collapse
|
37
|
Rothé B, Back R, Quinternet M, Bizarro J, Robert MC, Blaud M, Romier C, Manival X, Charpentier B, Bertrand E, Branlant C. Characterization of the interaction between protein Snu13p/15.5K and the Rsa1p/NUFIP factor and demonstration of its functional importance for snoRNP assembly. Nucleic Acids Res 2013; 42:2015-36. [PMID: 24234454 PMCID: PMC3919607 DOI: 10.1093/nar/gkt1091] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
The yeast Snu13p protein and its 15.5K human homolog both bind U4 snRNA and box C/D snoRNAs. They also bind the Rsa1p/NUFIP assembly factor, proposed to scaffold immature snoRNPs and to recruit the Hsp90-R2TP chaperone complex. However, the nature of the Snu13p/15.5K–Rsa1p/NUFIP interaction and its exact role in snoRNP assembly remained to be elucidated. By using biophysical, molecular and imaging approaches, here, we identify residues needed for Snu13p/15.5K–Rsa1p/NUFIP interaction. By NMR structure determination and docking approaches, we built a 3D model of the Snup13p–Rsa1p interface, suggesting that residues R249, R246 and K250 in Rsa1p and E72 and D73 in Snu13p form a network of electrostatic interactions shielded from the solvent by hydrophobic residues from both proteins and that residue W253 of Rsa1p is inserted in a hydrophobic cavity of Snu13p. Individual mutations of residues in yeast demonstrate the functional importance of the predicted interactions for both cell growth and snoRNP formation. Using archaeal box C/D sRNP 3D structures as templates, the association of Snu13p with Rsa1p is predicted to be exclusive of interactions in active snoRNPs. Rsa1p and NUFIP may thus prevent premature activity of pre-snoRNPs, and their removal may be a key step for active snoRNP production.
Collapse
Affiliation(s)
- Benjamin Rothé
- Ingénierie Moléculaire et Physiopathologie Articulaire (IMoPA), UMR 7365 CNRS Université de Lorraine, Biopôle de l'Université de Lorraine, Campus Biologie Santé, 9 avenue de la forêt de Haye, BP 184, 54505 Vandœuvre-lès-Nancy, France, FR CNRS-3209 (Ingénierie Moléculaire et Thérapeutique), CNRS, Université de Lorraine, Faculté de Médecine, Bâtiment Biopôle, BP 184, 54505 Vandœuvre-lès-Nancy Cedex, France, Equipe labellisée Ligue contre le Cancer, IGMM (Institut de Génétique Moléculaire de Montpellier), Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5535, Montpellier Cedex 5, France and IGBMC (Institut de Génétique et Biologie Moléculaire et Cellulaire), Département de Biologie et Génomique Structurales, Université de Strasbourg, CNRS, INSERM, 1 Rue Laurent Fries, BP 10142, 67404 Illkirch Cedex, France
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
38
|
Zhang L, Lin J, Ye K. Structural and functional analysis of the U3 snoRNA binding protein Rrp9. RNA (NEW YORK, N.Y.) 2013; 19:701-711. [PMID: 23509373 PMCID: PMC3677284 DOI: 10.1261/rna.037580.112] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2012] [Accepted: 02/06/2013] [Indexed: 06/01/2023]
Abstract
The U3 snoRNA is required for 18S rRNA processing and small subunit ribosome formation in eukaryotes. Different from other box C/D snoRNAs, U3 contains an extra 5' domain that pairs with pre-rRNA and a unique B/C motif essential for recruitment of the U3-specific Rrp9 protein. Here, we analyze the structure and function of Rrp9 with crystallographic, biochemical, and cellular approaches. Rrp9 is composed of a WD repeat domain and an N-terminal region. The crystal structures of the WD domain of yeast Rrp9 and its human ortholog U3-55K were determined, revealing a typical seven-bladed propeller fold. Several conserved surface patches on the WD domain were identified, and their function in RNP assembly and yeast growth were analyzed by mutagenesis. Prior association of Snu13 with the B/C motif was found to enhance the specific binding of the WD domain. We show that a conserved 7bc loop is crucial for specific recognition of U3, nucleolar localization of Rrp9, and yeast growth. In addition, we show that the N-terminal region of Rrp9 contains a bipartite nuclear localization signal that is dispensable for nucleolar localization. Our results provide insight into the functional sites of Rrp9.
Collapse
MESH Headings
- Amino Acid Sequence/genetics
- Binding Sites
- Crystallography, X-Ray
- Humans
- Nucleic Acid Conformation
- Protein Folding
- Protein Structure, Tertiary
- RNA Processing, Post-Transcriptional
- RNA, Ribosomal, 18S/genetics
- RNA, Ribosomal, 18S/metabolism
- RNA, Small Nucleolar/chemistry
- RNA, Small Nucleolar/genetics
- RNA-Binding Proteins/chemistry
- RNA-Binding Proteins/genetics
- RNA-Binding Proteins/metabolism
- Ribonucleoproteins, Small Nucleolar/chemistry
- Ribonucleoproteins, Small Nucleolar/genetics
- Ribonucleoproteins, Small Nucleolar/metabolism
- Ribosome Subunits, Small, Eukaryotic/genetics
- Saccharomyces cerevisiae/chemistry
- Saccharomyces cerevisiae/genetics
- Saccharomyces cerevisiae/metabolism
Collapse
Affiliation(s)
- Liman Zhang
- Graduate School of Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100730, China
- National Institute of Biological Sciences, Beijing, Beijing 102206, China
| | - Jinzhong Lin
- National Institute of Biological Sciences, Beijing, Beijing 102206, China
| | - Keqiong Ye
- Graduate School of Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100730, China
- National Institute of Biological Sciences, Beijing, Beijing 102206, China
| |
Collapse
|
39
|
Machado-Pinilla R, Liger D, Leulliot N, Meier UT. Mechanism of the AAA+ ATPases pontin and reptin in the biogenesis of H/ACA RNPs. RNA (NEW YORK, N.Y.) 2012; 18:1833-45. [PMID: 22923768 PMCID: PMC3446707 DOI: 10.1261/rna.034942.112] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
The AAA+ ATPases pontin and reptin function in a staggering array of cellular processes including chromatin remodeling, transcriptional regulation, DNA damage repair, and assembly of macromolecular complexes, such as RNA polymerase II and small nucleolar (sno) RNPs. However, the molecular mechanism for all of these AAA+ ATPase associated activities is unknown. Here we document that, during the biogenesis of H/ACA RNPs (including telomerase), the assembly factor SHQ1 holds the pseudouridine synthase NAP57/dyskerin in a viselike grip, and that pontin and reptin (as components of the R2TP complex) are required to pry NAP57 from SHQ1. Significantly, the NAP57 domain captured by SHQ1 harbors most mutations underlying X-linked dyskeratosis congenita (X-DC) implicating the interface between the two proteins as a target of this bone marrow failure syndrome. Homing in on the essential first steps of H/ACA RNP biogenesis, our findings provide the first insight into the mechanism of action of pontin and reptin in the assembly of macromolecular complexes.
Collapse
Affiliation(s)
- Rosario Machado-Pinilla
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx, New York 10461, USA
| | - Dominique Liger
- Institut de Biochimie et de Biophysique Moléculaire et Cellulaire, Université de Paris-Sud, CNRS-UMR8619, IFR115, 91405 Orsay Cedex, France
| | - Nicolas Leulliot
- Laboratoire de Cristallographie et RMN Biologiques, UMR CNRS 8015, Université Paris Descartes, Sorbonne Paris Cité, Faculté des Sciences Pharmaceutiques et Biologiques, 75006 Paris, France
| | - U. Thomas Meier
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx, New York 10461, USA
- Corresponding authorE-mail
| |
Collapse
|
40
|
Egan ED, Collins K. An enhanced H/ACA RNP assembly mechanism for human telomerase RNA. Mol Cell Biol 2012; 32:2428-39. [PMID: 22527283 PMCID: PMC3434483 DOI: 10.1128/mcb.00286-12] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2012] [Accepted: 04/12/2012] [Indexed: 11/20/2022] Open
Abstract
The integral telomerase RNA subunit templates the synthesis of telomeric repeats. The biological accumulation of human telomerase RNA (hTR) requires hTR H/ACA domain assembly with the same proteins that assemble on other human H/ACA RNAs. Despite this shared RNP composition, hTR accumulation is particularly sensitized to disruption by disease-linked H/ACA protein variants. We show that contrary to expectation, hTR-specific sequence requirements for biological accumulation do not act at an hTR-specific step of H/ACA RNP biogenesis; instead, they enhance hTR binding to the shared, chaperone-bound scaffold of H/ACA core proteins that mediates initial RNP assembly. We recapitulate physiological H/ACA RNP assembly with a preassembled NAF1/dyskerin/NOP10/NHP2 scaffold purified from cell extract and demonstrate that distributed sequence features of the hTR 3' hairpin synergize to improve scaffold binding. Our findings reveal that the hTR H/ACA domain is distinguished from other human H/ACA RNAs not by a distinct set of RNA-protein interactions but by an increased efficiency of RNP assembly. Our findings suggest a unifying mechanism for human telomerase deficiencies associated with H/ACA protein variants.
Collapse
Affiliation(s)
- Emily D Egan
- Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, California, USA
| | | |
Collapse
|