1
|
Sugiyama T. Finding new roles of classic biomolecular condensates in the nucleus: Lessons from fission yeast. CELL INSIGHT 2024; 3:100194. [PMID: 39228923 PMCID: PMC11369484 DOI: 10.1016/j.cellin.2024.100194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/17/2024] [Accepted: 07/29/2024] [Indexed: 09/05/2024]
Abstract
Decades have passed since the initial discovery of membrane-less nuclear compartments, commonly called nuclear bodies or nuclear condensates. These compartments have drawn attention to their unique characteristics and functions, especially after introducing "liquid-liquid phase separation" to this research field. While the majority of the studies on nuclear condensates have been conducted in multicellular organisms, recent genetic, biochemical, and cell biological analyses using the fission yeast Schizosaccharomyces pombe have yielded valuable insights into biomolecular condensates. This review article focuses on two 'classic' nuclear condensates and discusses how research using fission yeast has unveiled previously unknown functions of these known nuclear bodies.
Collapse
Affiliation(s)
- Tomoyasu Sugiyama
- School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| |
Collapse
|
2
|
Deng X, Yao Q, Horvath A, Jiang Z, Zhao J, Fischer T, Sugiyama T. The fission yeast ortholog of Coilin, Mug174, forms Cajal body-like nuclear condensates and is essential for cellular quiescence. Nucleic Acids Res 2024; 52:9174-9192. [PMID: 38828770 PMCID: PMC11347179 DOI: 10.1093/nar/gkae463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 05/08/2024] [Accepted: 05/16/2024] [Indexed: 06/05/2024] Open
Abstract
The Cajal body, a nuclear condensate, is crucial for ribonucleoprotein assembly, including small nuclear RNPs (snRNPs). While Coilin has been identified as an integral component of Cajal bodies, its exact function remains unclear. Moreover, no Coilin ortholog has been found in unicellular organisms to date. This study unveils Mug174 (Meiosis-upregulated gene 174) as the Coilin ortholog in the fission yeast Schizosaccharomyces pombe. Mug174 forms phase-separated condensates in vitro and is often associated with the nucleolus and the cleavage body in vivo. The generation of Mug174 foci relies on the trimethylguanosine (TMG) synthase Tgs1. Moreover, Mug174 interacts with Tgs1 and U snRNAs. Deletion of the mug174+ gene in S. pombe causes diverse pleiotropic phenotypes, encompassing defects in vegetative growth, meiosis, pre-mRNA splicing, TMG capping of U snRNAs, and chromosome segregation. In addition, we identified weak homology between Mug174 and human Coilin. Notably, human Coilin expressed in fission yeast colocalizes with Mug174. Critically, Mug174 is indispensable for the maintenance of and transition from cellular quiescence. These findings highlight the Coilin ortholog in fission yeast and suggest that the Cajal body is implicated in cellular quiescence, thereby preventing human diseases.
Collapse
Affiliation(s)
- Xiaoling Deng
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Qinglian Yao
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Attila Horvath
- The John Curtin School of Medical Research, The Australian National University, Canberra 2601, Australia
| | - Ziling Jiang
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Junjie Zhao
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Tamás Fischer
- The John Curtin School of Medical Research, The Australian National University, Canberra 2601, Australia
| | - Tomoyasu Sugiyama
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| |
Collapse
|
3
|
Li Q, Liu Y, Zhang X. Biomolecular condensates in plant RNA silencing: insights into formation, function, and stress responses. THE PLANT CELL 2024; 36:227-245. [PMID: 37772963 PMCID: PMC10827315 DOI: 10.1093/plcell/koad254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 09/14/2023] [Accepted: 09/14/2023] [Indexed: 09/30/2023]
Abstract
Biomolecular condensates are dynamic structures formed through diverse mechanisms, including liquid-liquid phase separation. These condensates have emerged as crucial regulators of cellular processes in eukaryotic cells, enabling the compartmentalization of specific biological reactions while allowing for dynamic exchange of molecules with the surrounding environment. RNA silencing, a conserved gene regulatory mechanism mediated by small RNAs (sRNAs), plays pivotal roles in various biological processes. Multiple types of biomolecular condensate, including dicing bodies, processing bodies, small interfering RNA bodies, and Cajal bodies, have been identified as key players in RNA silencing pathways. These biomolecular condensates provide spatial compartmentation for the biogenesis, loading, action, and turnover of small RNAs. Moreover, they actively respond to stresses, such as viral infections, and modulate RNA silencing activities during stress responses. This review summarizes recent advances in understanding of dicing bodies and other biomolecular condensates involved in RNA silencing. We explore their formation, roles in RNA silencing, and contributions to antiviral resistance responses. This comprehensive overview provides insights into the functional significance of biomolecular condensates in RNA silencing and expands our understanding of their roles in gene expression and stress responses in plants.
Collapse
Affiliation(s)
- Qi Li
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
| | - Yang Liu
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
| | - Xiaoming Zhang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
- HainanYazhou Bay Seed Lab, Sanya, China
| |
Collapse
|
4
|
Geisler MS, Kemp JP, Duronio RJ. Histone locus bodies: a paradigm for how nuclear biomolecular condensates control cell cycle regulated gene expression. Nucleus 2023; 14:2293604. [PMID: 38095604 PMCID: PMC10730174 DOI: 10.1080/19491034.2023.2293604] [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: 09/29/2023] [Accepted: 12/07/2023] [Indexed: 12/18/2023] Open
Abstract
Histone locus bodies (HLBs) are biomolecular condensates that assemble at replication-dependent (RD) histone genes in animal cells. These genes produce unique mRNAs that are not polyadenylated and instead end in a conserved 3' stem loop critical for coordinated production of histone proteins during S phase of the cell cycle. Several evolutionarily conserved factors necessary for synthesis of RD histone mRNAs concentrate only in the HLB. Moreover, because HLBs are present throughout the cell cycle even though RD histone genes are only expressed during S phase, changes in HLB composition during cell cycle progression drive much of the cell cycle regulation of RD histone gene expression. Thus, HLBs provide a powerful opportunity to determine the cause-and-effect relationships between nuclear body formation and cell cycle regulated gene expression. In this review, we focus on progress during the last five years that has advanced our understanding of HLB biology.
Collapse
Affiliation(s)
- Mark S. Geisler
- Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, NC, USA
| | - James P. Kemp
- Integrative Program for Biological and Genome Sciences, University of North Carolina, Chapel Hill, NC, USA
| | - Robert J. Duronio
- Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, NC, USA
- Integrative Program for Biological and Genome Sciences, University of North Carolina, Chapel Hill, NC, USA
- Department of Biology, University of North Carolina, Chapel Hill, NC, USA
- Department of Genetics, University of North Carolina, Chapel Hill, NC, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC, USA
| |
Collapse
|
5
|
Staněk D. Coilin and Cajal bodies. Nucleus 2023; 14:2256036. [PMID: 37682044 PMCID: PMC10494742 DOI: 10.1080/19491034.2023.2256036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 08/24/2023] [Accepted: 08/28/2023] [Indexed: 09/09/2023] Open
Abstract
The nucleus of higher eukaryotes contains a number of structures that concentrate specific biomolecules and play distinct roles in nuclear metabolism. In recent years, the molecular mechanisms controlling their formation have been intensively studied. In this brief review, I focus on coilin and Cajal bodies. Coilin is a key scaffolding protein of Cajal bodies that is evolutionarily conserved in metazoans. Cajal bodies are thought to be one of the archetypal nuclear structures involved in the metabolism of several short non-coding nuclear RNAs. Yet surprisingly little is known about the structure and function of coilin, and a comprehensive model to explain the origin of Cajal bodies is also lacking. Here, I summarize recent results on Cajal bodies and coilin and discuss them in the context of the last three decades of research in this field.
Collapse
Affiliation(s)
- David Staněk
- Laboratory of RNA Biology, Institute of Molecular Genetics, Czech Academy of Sciences, Prague, Czech Republic
| |
Collapse
|
6
|
Kanno T, Chiou P, Wu MT, Lin WD, Matzke A, Matzke M. A GFP splicing reporter in a coilin mutant background reveals links between alternative splicing, siRNAs, and coilin function in Arabidopsis thaliana. G3 (BETHESDA, MD.) 2023; 13:jkad175. [PMID: 37539868 PMCID: PMC10542627 DOI: 10.1093/g3journal/jkad175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2023] [Revised: 02/25/2023] [Accepted: 06/30/2023] [Indexed: 08/05/2023]
Abstract
Coilin is a scaffold protein essential for the structure of Cajal bodies, which are nucleolar-associated, nonmembranous organelles that coordinate the assembly of nuclear ribonucleoproteins (RNPs) including spliceosomal snRNPs. To study coilin function in plants, we conducted a genetic suppressor screen using a coilin (coi1) mutant in Arabidopsis thaliana and performed an immunoprecipitation-mass spectrometry analysis on coilin protein. The coi1 mutations modify alternative splicing of a GFP reporter gene, resulting in a hyper-GFP phenotype in young coi1 seedlings relative to the intermediate wild-type level. As shown here, this hyper-GFP phenotype is extinguished in older coi1 seedlings by posttranscriptional gene silencing triggered by siRNAs derived from aberrant splice variants of GFP pre-mRNA. In the coi1 suppressor screen, we identified suppressor mutations in WRAP53, a putative coilin-interacting protein; SMU2, a predicted splicing factor; and ZCH1, an incompletely characterized zinc finger protein. These suppressor mutations return the hyper-GFP fluorescence of young coi1 seedlings to the intermediate wild-type level. Additionally, coi1 zch1 mutants display more extensive GFP silencing and elevated levels of GFP siRNAs, suggesting the involvement of wild-type ZCH1 in siRNA biogenesis or stability. The immunoprecipitation-mass spectrometry analysis reinforced the roles of coilin in pre-mRNA splicing, nucleolar chromatin structure, and rRNA processing. The participation of coilin in these processes, at least some of which incorporate small RNAs, supports the hypothesis that coilin provides a chaperone for small RNA trafficking. Our study demonstrates the usefulness of the GFP splicing reporter for investigating alternative splicing, ribosome biogenesis, and siRNA-mediated silencing in the context of coilin function.
Collapse
Affiliation(s)
- Tatsuo Kanno
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 115201, Taiwan
| | - Phebe Chiou
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 115201, Taiwan
| | - Ming-Tsung Wu
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 115201, Taiwan
- Genenet Technology (UK) Limited, 128 City Road, London EC1V 2NX, UK
| | - Wen-Dar Lin
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 115201, Taiwan
| | - Antonius Matzke
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 115201, Taiwan
| | - Marjori Matzke
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 115201, Taiwan
| |
Collapse
|
7
|
Taliansky ME, Love AJ, Kołowerzo-Lubnau A, Smoliński DJ. Cajal bodies: Evolutionarily conserved nuclear biomolecular condensates with properties unique to plants. THE PLANT CELL 2023; 35:3214-3235. [PMID: 37202374 PMCID: PMC10473218 DOI: 10.1093/plcell/koad140] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 04/24/2023] [Accepted: 04/27/2023] [Indexed: 05/20/2023]
Abstract
Proper orchestration of the thousands of biochemical processes that are essential to the life of every cell requires highly organized cellular compartmentalization of dedicated microenvironments. There are 2 ways to create this intracellular segregation to optimize cellular function. One way is to create specific organelles, enclosed spaces bounded by lipid membranes that regulate macromolecular flux in and out of the compartment. A second way is via membraneless biomolecular condensates that form due to to liquid-liquid phase separation. Although research on these membraneless condensates has historically been performed using animal and fungal systems, recent studies have explored basic principles governing the assembly, properties, and functions of membraneless compartments in plants. In this review, we discuss how phase separation is involved in a variety of key processes occurring in Cajal bodies (CBs), a type of biomolecular condensate found in nuclei. These processes include RNA metabolism, formation of ribonucleoproteins involved in transcription, RNA splicing, ribosome biogenesis, and telomere maintenance. Besides these primary roles of CBs, we discuss unique plant-specific functions of CBs in RNA-based regulatory pathways such as nonsense-mediated mRNA decay, mRNA retention, and RNA silencing. Finally, we summarize recent progress and discuss the functions of CBs in responses to pathogen attacks and abiotic stresses, responses that may be regulated via mechanisms governed by polyADP-ribosylation. Thus, plant CBs are emerging as highly complex and multifunctional biomolecular condensates that are involved in a surprisingly diverse range of molecular mechanisms that we are just beginning to appreciate.
Collapse
Affiliation(s)
| | - Andrew J Love
- The James Hutton Institute, Invergowrie, Dundee DD2 5DA, UK
| | - Agnieszka Kołowerzo-Lubnau
- Department of Cellular and Molecular Biology, Nicolaus Copernicus University, Lwowska 1, 87-100 Torun, Poland
- Centre for Modern Interdisciplinary Technologies, Nicolaus Copernicus University, Wilenska 4, 87-100 Torun, Poland
| | - Dariusz Jan Smoliński
- Department of Cellular and Molecular Biology, Nicolaus Copernicus University, Lwowska 1, 87-100 Torun, Poland
- Centre for Modern Interdisciplinary Technologies, Nicolaus Copernicus University, Wilenska 4, 87-100 Torun, Poland
| |
Collapse
|
8
|
Bogolyubov DS, Chistyakova LV, Goodkov AV. Glomerulosomes: morphologically distinct nuclear organelles of unknown nature. PROTOPLASMA 2022; 259:1409-1415. [PMID: 35103866 DOI: 10.1007/s00709-022-01742-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 01/21/2022] [Indexed: 06/14/2023]
Abstract
The nucleus of some representatives of the genus Pelomyxa (Amoebozoa, Archamoebae, Pelobiontida) contains specific bodies (membrane-less organelles). They may be either embedded in the nucleolar mass or detached from the nucleolus. We termed these nuclear bodies the glomerulosomes for their characteristic ultrastructural appearance. The glomerulosomes are distinct nuclear bodies, about 1 μm in diameter. The morphological and diagnostic unit of a glomerulosome is an electron-dense thread/string, about 30-40 nm in thickness. These threads are not direct continuation of the nucleolar material. The threads create the unique geometric appearance of the glomerulosome by being organized into precisely parallel rows/cords. Each cord of the threads can curve at different angles within the glomerulosome body, but the threads themselves are not coiled. Nowadays, the glomerulosomes have been discovered in P. palustris, P. stagnalis, P. paradoxa, and Pelomyxa sp. Despite the unique appearance of glomerulosomes, their existence may be a more common phenomenon in eukaryotic cells than just a specific feature of the nucleus of elected pelomyxes.
Collapse
Affiliation(s)
- Dmitry S Bogolyubov
- Laboratory of Cell Morphology, Institute of Cytology of the Russian Academy of Sciences, St. Petersburg, 194064, Russia.
| | | | - Andrew V Goodkov
- Laboratory of Cytology of Unicellular Organisms, Institute of Cytology of the Russian Academy of Sciences, St. Petersburg, 194064, Russia
| |
Collapse
|
9
|
Courchaine E, Gelles-Watnick S, Machyna M, Straube K, Sauyet S, Enright J, Neugebauer KM. The coilin N-terminus mediates multivalent interactions between coilin and Nopp140 to form and maintain Cajal bodies. Nat Commun 2022; 13:6005. [PMID: 36224177 PMCID: PMC9556525 DOI: 10.1038/s41467-022-33434-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2021] [Accepted: 09/16/2022] [Indexed: 11/25/2022] Open
Abstract
Cajal bodies (CBs) are ubiquitous nuclear membraneless organelles (MLOs) that concentrate and promote efficient biogenesis of snRNA-protein complexes involved in splicing (snRNPs). Depletion of the CB scaffolding protein coilin disperses snRNPs, making CBs a model system for studying the structure and function of MLOs. Although it is assumed that CBs form through condensation, the biomolecular interactions responsible remain elusive. Here, we discover the unexpected capacity of coilin’s N-terminal domain (NTD) to form extensive fibrils in the cytoplasm and discrete nuclear puncta in vivo. Single amino acid mutational analysis reveals distinct molecular interactions between coilin NTD proteins to form fibrils and additional NTD interactions with the nuclear Nopp140 protein to form puncta. We provide evidence that Nopp140 has condensation capacity and is required for CB assembly. From these observations, we propose a model in which coilin NTD–NTD mediated assemblies make multivalent contacts with Nopp140 to achieve biomolecular condensation in the nucleus. Cajal bodies are membraneless organelles scaffolded by coilin protein. Here, coilin–coilin and coilin–Nopp140 interaction sites are identified and perturbed, revealing coilin’s capacity to form long fibrils and be remodeled into spherical structures.
Collapse
Affiliation(s)
- Edward Courchaine
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Sara Gelles-Watnick
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Martin Machyna
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Korinna Straube
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Sarah Sauyet
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Jade Enright
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Karla M Neugebauer
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA.
| |
Collapse
|
10
|
Lacroix E, Audas TE. Keeping up with the condensates: The retention, gain, and loss of nuclear membrane-less organelles. Front Mol Biosci 2022; 9:998363. [PMID: 36203874 PMCID: PMC9530788 DOI: 10.3389/fmolb.2022.998363] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Accepted: 08/19/2022] [Indexed: 12/04/2022] Open
Abstract
In recent decades, a growing number of biomolecular condensates have been identified in eukaryotic cells. These structures form through phase separation and have been linked to a diverse array of cellular processes. While a checklist of established membrane-bound organelles is present across the eukaryotic domain, less is known about the conservation of membrane-less subcellular structures. Many of these structures can be seen throughout eukaryotes, while others are only thought to be present in metazoans or a limited subset of species. In particular, the nucleus is a hub of biomolecular condensates. Some of these subnuclear domains have been found in a broad range of organisms, which is a characteristic often attributed to essential functionality. However, this does not always appear to be the case. For example, the nucleolus is critical for ribosomal biogenesis and is present throughout the eukaryotic domain, while the Cajal bodies are believed to be similarly conserved, yet these structures are dispensable for organismal survival. Likewise, depletion of the Drosophila melanogaster omega speckles reduces viability, despite the apparent absence of this domain in higher eukaryotes. By reviewing primary research that has analyzed the presence of specific condensates (nucleoli, Cajal bodies, amyloid bodies, nucleolar aggresomes, nuclear speckles, nuclear paraspeckles, nuclear stress bodies, PML bodies, omega speckles, NUN bodies, mei2 dots) in a cross-section of organisms (e.g., human, mouse, D. melanogaster, Caenorhabditis elegans, yeast), we adopt a human-centric view to explore the emergence, retention, and absence of a subset of nuclear biomolecular condensates. This overview is particularly important as numerous biomolecular condensates have been linked to human disease, and their presence in additional species could unlock new and well characterized model systems for health research.
Collapse
Affiliation(s)
- Emma Lacroix
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC, Canada
- Centre for Cell Biology, Development, and Disease, Simon Fraser University, Burnaby, BC, Canada
| | - Timothy E. Audas
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC, Canada
- Centre for Cell Biology, Development, and Disease, Simon Fraser University, Burnaby, BC, Canada
- *Correspondence: Timothy E. Audas,
| |
Collapse
|
11
|
Abulfaraj AA, Alhoraibi HM, Mariappan K, Bigeard J, Zhang H, Almeida-Trapp M, Artyukh O, Abdulhakim F, Parween S, Pflieger D, Blilou I, Hirt H, Rayapuram N. Analysis of the Arabidopsis coilin mutant reveals a positive role of AtCOILIN in plant immunity. PLANT PHYSIOLOGY 2022; 190:745-761. [PMID: 35674377 PMCID: PMC9434284 DOI: 10.1093/plphys/kiac280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 05/18/2022] [Indexed: 06/15/2023]
Abstract
Biogenesis of ribonucleoproteins occurs in dynamic subnuclear compartments called Cajal bodies (CBs). COILIN is a critical scaffolding component essential for CB formation, composition, and activity. We recently showed that Arabidopsis (Arabidopsis thaliana) AtCOILIN is phosphorylated in response to bacterial elicitor treatment. Here, we further investigated the role of AtCOILIN in plant innate immunity. Atcoilin mutants are compromised in defense responses to bacterial pathogens. Besides confirming a role of AtCOILIN in alternative splicing (AS), Atcoilin showed differential expression of genes that are distinct from those of AS, including factors involved in RNA biogenesis, metabolism, plant immunity, and phytohormones. Atcoilin mutant plants have reduced levels of defense phytohormones. As expected, the mutant plants were more sensitive to the necrotrophic fungal pathogen Botrytis cinerea. Our findings reveal an important role for AtCOILIN in innate plant immunity.
Collapse
Affiliation(s)
- Aala A Abulfaraj
- Biological Sciences Department, College of Science & Arts, King Abdulaziz University, Rabigh 21911, Saudi Arabia
| | - Hanna M Alhoraibi
- Department of Biochemistry, Faculty of Science, King Abdulaziz University, 21551 Jeddah, Saudi Arabia
| | - Kiruthiga Mariappan
- Division of Biological and Environmental Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal 23955, Saudi Arabia
| | - Jean Bigeard
- Institute of Plant Sciences Paris Saclay (IPS2), CNRS, INRAE, Univ Evry, Université Paris-Saclay, Université de Paris, Orsay 91405, France
| | - Huoming Zhang
- Corelabs, King Abdullah University of Science and Technology, Thuwal 23955, Saudi Arabia
| | - Marilia Almeida-Trapp
- Division of Biological and Environmental Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal 23955, Saudi Arabia
| | - Olga Artyukh
- Division of Biological and Environmental Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal 23955, Saudi Arabia
| | - Fatimah Abdulhakim
- Division of Biological and Environmental Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal 23955, Saudi Arabia
| | - Sabiha Parween
- Division of Biological and Environmental Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal 23955, Saudi Arabia
| | - Delphine Pflieger
- Universite Grenoble Alpes, INSERM, CEA, UMR BioSanté U1292, CNRS, CEA, FR2048 38000, Grenoble, France
| | - Ikram Blilou
- Division of Biological and Environmental Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal 23955, Saudi Arabia
| | | | | |
Collapse
|
12
|
Muñoz-Díaz E, Sáez-Vásquez J. Nuclear dynamics: Formation of bodies and trafficking in plant nuclei. FRONTIERS IN PLANT SCIENCE 2022; 13:984163. [PMID: 36082296 PMCID: PMC9445803 DOI: 10.3389/fpls.2022.984163] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 08/04/2022] [Indexed: 06/01/2023]
Abstract
The existence of the nucleus distinguishes prokaryotes and eukaryotes. Apart from containing most of the genetic material, the nucleus possesses several nuclear bodies composed of protein and RNA molecules. The nucleus is separated from the cytoplasm by a double membrane, regulating the trafficking of molecules in- and outwards. Here, we investigate the composition and function of the different plant nuclear bodies and molecular clues involved in nuclear trafficking. The behavior of the nucleolus, Cajal bodies, dicing bodies, nuclear speckles, cyclophilin-containing bodies, photobodies and DNA damage foci is analyzed in response to different abiotic stresses. Furthermore, we research the literature to collect the different protein localization signals that rule nucleocytoplasmic trafficking. These signals include the different types of nuclear localization signals (NLSs) for nuclear import, and the nuclear export signals (NESs) for nuclear export. In contrast to these unidirectional-movement signals, the existence of nucleocytoplasmic shuttling signals (NSSs) allows bidirectional movement through the nuclear envelope. Likewise, nucleolar signals are also described, which mainly include the nucleolar localization signals (NoLSs) controlling nucleolar import. In contrast, few examples of nucleolar export signals, called nucleoplasmic localization signals (NpLSs) or nucleolar export signals (NoESs), have been reported. The existence of consensus sequences for these localization signals led to the generation of prediction tools, allowing the detection of these signals from an amino acid sequence. Additionally, the effect of high temperatures as well as different post-translational modifications in nuclear and nucleolar import and export is discussed.
Collapse
Affiliation(s)
- Eduardo Muñoz-Díaz
- Centre National de la Recherche Scientifique (CNRS), Laboratoire Génome et Développement des Plantes, UMR 5096, Perpignan, France
- Univ. Perpignan Via Domitia, Laboratoire Génome et Développement des Plantes, UMR 5096, Perpignan, France
| | - Julio Sáez-Vásquez
- Centre National de la Recherche Scientifique (CNRS), Laboratoire Génome et Développement des Plantes, UMR 5096, Perpignan, France
- Univ. Perpignan Via Domitia, Laboratoire Génome et Développement des Plantes, UMR 5096, Perpignan, France
| |
Collapse
|
13
|
Suzuki H, Abe R, Shimada M, Hirose T, Hirose H, Noguchi K, Ike Y, Yasui N, Furugori K, Yamaguchi Y, Toyoda A, Suzuki Y, Yamamoto T, Saitoh N, Sato S, Tomomori-Sato C, Conaway RC, Conaway JW, Takahashi H. The 3' Pol II pausing at replication-dependent histone genes is regulated by Mediator through Cajal bodies' association with histone locus bodies. Nat Commun 2022; 13:2905. [PMID: 35614107 PMCID: PMC9133132 DOI: 10.1038/s41467-022-30632-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 05/10/2022] [Indexed: 11/09/2022] Open
Abstract
Non-polyadenylated mRNAs of replication-dependent histones (RDHs) are synthesized by RNA polymerase II (Pol II) at histone locus bodies (HLBs). HLBs frequently associate with Cajal bodies (CBs), in which 3'-end processing factors for RDH genes are enriched; however, this association's role in transcription termination of RDH genes remains unclear. Here, we show that Pol II pauses immediately upstream of transcript end sites of RDH genes and Mediator plays a role in this Pol II pausing through CBs' association with HLBs. Disruption of the Mediator docking site for Little elongation complex (LEC)-Cap binding complex (CBC)-Negative elongation factor (NELF), components of CBs, interferes with CBs' association with HLBs and 3' Pol II pausing, resulting in increased aberrant unprocessed RDH gene transcripts. Our findings suggest Mediator's involvement in CBs' association with HLBs to facilitate 3' Pol II pausing and subsequent 3'-end processing of RDH genes by supplying 3'-end processing factors.
Collapse
Affiliation(s)
- Hidefumi Suzuki
- Department of Molecular Biology, Yokohama City University Graduate School of Medical Science, 3-9 Fukuura, Kanazawa-ku, Yokohama, Kanagawa, 236-0004, Japan
| | - Ryota Abe
- Department of Molecular Biology, Yokohama City University Graduate School of Medical Science, 3-9 Fukuura, Kanazawa-ku, Yokohama, Kanagawa, 236-0004, Japan
| | - Miho Shimada
- Department of Molecular Biology, Yokohama City University Graduate School of Medical Science, 3-9 Fukuura, Kanazawa-ku, Yokohama, Kanagawa, 236-0004, Japan
| | - Tomonori Hirose
- Department of Molecular Biology, Yokohama City University Graduate School of Medical Science, 3-9 Fukuura, Kanazawa-ku, Yokohama, Kanagawa, 236-0004, Japan
| | - Hiroko Hirose
- Department of Molecular Biology, Yokohama City University Graduate School of Medical Science, 3-9 Fukuura, Kanazawa-ku, Yokohama, Kanagawa, 236-0004, Japan
| | - Keisuke Noguchi
- Department of Molecular Biology, Yokohama City University Graduate School of Medical Science, 3-9 Fukuura, Kanazawa-ku, Yokohama, Kanagawa, 236-0004, Japan
| | - Yoko Ike
- Department of Molecular Biology, Yokohama City University Graduate School of Medical Science, 3-9 Fukuura, Kanazawa-ku, Yokohama, Kanagawa, 236-0004, Japan
| | - Nanami Yasui
- Department of Molecular Biology, Yokohama City University Graduate School of Medical Science, 3-9 Fukuura, Kanazawa-ku, Yokohama, Kanagawa, 236-0004, Japan
| | - Kazuki Furugori
- Department of Molecular Biology, Yokohama City University Graduate School of Medical Science, 3-9 Fukuura, Kanazawa-ku, Yokohama, Kanagawa, 236-0004, Japan
| | - Yuki Yamaguchi
- School of Life Science and Technology, Tokyo Institute of Technology, 4259 Nagatsuta, Yokohama, Kanagawa, 226-8501, Japan
| | - Atsushi Toyoda
- Comparative Genomics Laboratory, National Institute of Genetics, 1111 Yata, Mishima, Shizuoka, 411-8540, Japan
| | - Yutaka Suzuki
- Laboratory of Systems Genomics, Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba, 277-8562, Japan
| | - Tatsuro Yamamoto
- Division of Cancer Biology, The Cancer Institute of JFCR, 3-8-31 Ariake, Koto-ku, Tokyo, 135-8550, Japan
| | - Noriko Saitoh
- Division of Cancer Biology, The Cancer Institute of JFCR, 3-8-31 Ariake, Koto-ku, Tokyo, 135-8550, Japan
| | - Shigeo Sato
- Stowers Institute for Medical Research, 1000E 50th Street, Kansas City, MO, 64110, USA
| | - Chieri Tomomori-Sato
- Stowers Institute for Medical Research, 1000E 50th Street, Kansas City, MO, 64110, USA
| | - Ronald C Conaway
- Stowers Institute for Medical Research, 1000E 50th Street, Kansas City, MO, 64110, USA.,Department of Biochemistry & Molecular Biology, University of Kansas Medical Center, Kansas City, MO, 66160, USA
| | - Joan W Conaway
- Stowers Institute for Medical Research, 1000E 50th Street, Kansas City, MO, 64110, USA.,Department of Biochemistry & Molecular Biology, University of Kansas Medical Center, Kansas City, MO, 66160, USA
| | - Hidehisa Takahashi
- Department of Molecular Biology, Yokohama City University Graduate School of Medical Science, 3-9 Fukuura, Kanazawa-ku, Yokohama, Kanagawa, 236-0004, Japan.
| |
Collapse
|
14
|
Basello DA, Matera AG, Staněk D. A point mutation in human coilin prevents Cajal body formation. J Cell Sci 2022; 135:274900. [PMID: 35356988 PMCID: PMC9080554 DOI: 10.1242/jcs.259587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Accepted: 03/20/2022] [Indexed: 11/20/2022] Open
Abstract
Coilin is a conserved protein essential for integrity of nuclear membrane-less inclusions called Cajal bodies. Here, we report an amino-acid substitution (p.K496E) found in a widely-used human EGFP-coilin construct that has a dominant negative effect on Cajal body formation. We show that this coilin-K496E variant fails to rescue Cajal bodies in cells lacking endogenous coilin, whereas the wild-type construct restores Cajal bodies in mouse and human coilin-knockout cells. In cells containing endogenous coilin, both the wild-type and K496E variant proteins accumulate in Cajal bodies. However, high-level overexpression of coilin-K496E causes Cajal body disintegration. Thus, a mutation in the C-terminal region of human coilin can disrupt Cajal body assembly. Caution should be used when interpreting data from coilin plasmids that are derived from this variant (currently deposited at Addgene).
Collapse
Affiliation(s)
- Davide A Basello
- Institute of Molecular Genetics, Czech Academy of Science, Prague, Czech Republic.,Faculty of Science, Charles University, Prague, Czech Republic
| | - A Gregory Matera
- Integrative Program for Biological and Genome Sciences, and Department of Biology, University of North Carolina, Chapel Hill, USA
| | - David Staněk
- Institute of Molecular Genetics, Czech Academy of Science, Prague, Czech Republic
| |
Collapse
|
15
|
Chakravarti A, Thirimanne HN, Brown S, Calvi BR. Drosophila p53 isoforms have overlapping and distinct functions in germline genome integrity and oocyte quality control. eLife 2022; 11:61389. [PMID: 35023826 PMCID: PMC8758136 DOI: 10.7554/elife.61389] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Accepted: 12/13/2021] [Indexed: 12/13/2022] Open
Abstract
p53 gene family members in humans and other organisms encode a large number of protein isoforms whose functions are largely undefined. Using Drosophila as a model, we find that a p53B isoform is expressed predominantly in the germline where it colocalizes with p53A into subnuclear bodies. It is only p53A, however, that mediates the apoptotic response to ionizing radiation in the germline and soma. In contrast, p53A and p53B are both required for the normal repair of meiotic DNA breaks, an activity that is more crucial when meiotic recombination is defective. We find that in oocytes with persistent DNA breaks p53A is also required to activate a meiotic pachytene checkpoint. Our findings indicate that Drosophila p53 isoforms have DNA lesion and cell type-specific functions, with parallels to the functions of mammalian p53 family members in the genotoxic stress response and oocyte quality control.
Collapse
Affiliation(s)
| | | | - Savanna Brown
- Department of Biology, Indiana University, Bloomington, United States
| | - Brian R Calvi
- Department of Biology, Indiana University, Bloomington, United States
| |
Collapse
|
16
|
Dissecting the complexity of biomolecular condensates. Biochem Soc Trans 2021; 48:2591-2602. [PMID: 33300985 DOI: 10.1042/bst20200351] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 10/29/2020] [Accepted: 11/02/2020] [Indexed: 11/17/2022]
Abstract
Biomolecular condensates comprise a diverse and ubiquitous class of membraneless organelles. Condensate assembly is often described by liquid-liquid phase separation. While this process explains many key features, it cannot account for the compositional or architectural complexity that condensates display in cells. Recent work has begun to dissect the rich network of intermolecular interactions that give rise to biomolecular condensates. Here, we review the latest results from theory, simulations and experiments, and discuss what they reveal about the structure-function relationship of condensates.
Collapse
|
17
|
Drosophila to Explore Nucleolar Stress. Int J Mol Sci 2021; 22:ijms22136759. [PMID: 34201772 PMCID: PMC8267670 DOI: 10.3390/ijms22136759] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 06/16/2021] [Accepted: 06/18/2021] [Indexed: 01/29/2023] Open
Abstract
Nucleolar stress occurs when ribosome production or function declines. Nucleolar stress in stem cells or progenitor cells often leads to disease states called ribosomopathies. Drosophila offers a robust system to explore how nucleolar stress causes cell cycle arrest, apoptosis, or autophagy depending on the cell type. We provide an overview of nucleolar stress in Drosophila by depleting nucleolar phosphoprotein of 140 kDa (Nopp140), a ribosome biogenesis factor (RBF) in nucleoli and Cajal bodies (CBs). The depletion of Nopp140 in eye imaginal disc cells generates eye deformities reminiscent of craniofacial deformities associated with the Treacher Collins syndrome (TCS), a human ribosomopathy. We show the activation of c-Jun N-terminal Kinase (JNK) in Drosophila larvae homozygous for a Nopp140 gene deletion. JNK is known to induce the expression of the pro-apoptotic Hid protein and autophagy factors Atg1, Atg18.1, and Atg8a; thus, JNK is a central regulator in Drosophila nucleolar stress. Ribosome abundance declines upon Nopp140 loss, but unusual cytoplasmic granules accumulate that resemble Processing (P) bodies based on marker proteins, Decapping Protein 1 (DCP1) and Maternal expression at 31B (Me31B). Wild type brain neuroblasts (NBs) express copious amounts of endogenous coilin, but coilin levels decline upon nucleolar stress in most NB types relative to the Mushroom body (MB) NBs. MB NBs exhibit resilience against nucleolar stress as they maintain normal coilin, Deadpan, and EdU labeling levels.
Collapse
|
18
|
Emenecker RJ, Holehouse AS, Strader LC. Biological Phase Separation and Biomolecular Condensates in Plants. ANNUAL REVIEW OF PLANT BIOLOGY 2021; 72:17-46. [PMID: 33684296 PMCID: PMC8221409 DOI: 10.1146/annurev-arplant-081720-015238] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
A surge in research focused on understanding the physical principles governing the formation, properties, and function of membraneless compartments has occurred over the past decade. Compartments such as the nucleolus, stress granules, and nuclear speckles have been designated as biomolecular condensates to describe their shared property of spatially concentrating biomolecules. Although this research has historically been carried out in animal and fungal systems, recent work has begun to explore whether these same principles are relevant in plants. Effectively understanding and studying biomolecular condensates require interdisciplinary expertise that spans cell biology, biochemistry, and condensed matter physics and biophysics. As such, some involved concepts may be unfamiliar to any given individual. This review focuses on introducing concepts essential to the study of biomolecular condensates and phase separation for biologists seeking to carry out research in this area and further examines aspects of biomolecular condensates that are relevant to plant systems.
Collapse
Affiliation(s)
- Ryan J Emenecker
- Department of Biology, Washington University, St. Louis, Missouri 63130, USA
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri 63110, USA;
- Center for Science and Engineering of Living Systems, Washington University, St. Louis, Missouri 63130, USA
- Center for Engineering MechanoBiology, Washington University, St. Louis, Missouri 63130, USA
| | - Alex S Holehouse
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri 63110, USA;
- Center for Science and Engineering of Living Systems, Washington University, St. Louis, Missouri 63130, USA
| | - Lucia C Strader
- Center for Science and Engineering of Living Systems, Washington University, St. Louis, Missouri 63130, USA
- Center for Engineering MechanoBiology, Washington University, St. Louis, Missouri 63130, USA
- Department of Biology, Duke University, Durham, North Carolina 27708, USA;
| |
Collapse
|
19
|
Emenecker RJ, Holehouse AS, Strader LC. Emerging Roles for Phase Separation in Plants. Dev Cell 2020; 55:69-83. [PMID: 33049212 PMCID: PMC7577370 DOI: 10.1016/j.devcel.2020.09.010] [Citation(s) in RCA: 72] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 08/19/2020] [Accepted: 09/02/2020] [Indexed: 12/12/2022]
Abstract
The plant cell internal environment is a dynamic, intricate landscape composed of many intracellular compartments. Cells organize some cellular components through formation of biomolecular condensates-non-stoichiometric assemblies of protein and/or nucleic acids. In many cases, phase separation appears to either underly or contribute to the formation of biomolecular condensates. Many canonical membraneless compartments within animal cells form in a manner that is at least consistent with phase separation, including nucleoli, stress granules, Cajal bodies, and numerous additional bodies, regulated by developmental and environmental stimuli. In this Review, we examine the emerging roles for phase separation in plants. Further, drawing on studies carried out in other organisms, we identify cellular phenomenon in plants that might also arise via phase separation. We propose that plants make use of phase separation to a much greater extent than has been previously appreciated, implicating phase separation as an evolutionarily ancient mechanism for cellular organization.
Collapse
Affiliation(s)
- Ryan J Emenecker
- Department of Biology, Washington University, St. Louis, MO 63130, USA; Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO 63110, USA; Center for Science and Engineering Living Systems (CSELS), Washington University, St. Louis, MO 63130, USA; Center for Engineering Mechanobiology, Washington University, St. Louis, MO 63130, USA
| | - Alex S Holehouse
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO 63110, USA; Center for Science and Engineering Living Systems (CSELS), Washington University, St. Louis, MO 63130, USA.
| | - Lucia C Strader
- Center for Science and Engineering Living Systems (CSELS), Washington University, St. Louis, MO 63130, USA; Center for Engineering Mechanobiology, Washington University, St. Louis, MO 63130, USA; Department of Biology, Duke University, Durham, NC 27708, USA.
| |
Collapse
|
20
|
Logan MK, McLaurin DM, Hebert MD. Synergistic interactions between Cajal bodies and the miRNA processing machinery. Mol Biol Cell 2020; 31:1561-1569. [PMID: 32432989 PMCID: PMC7521794 DOI: 10.1091/mbc.e20-02-0144] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Cajal bodies (CBs) are subnuclear domains involved in the formation of ribonucleoproteins (RNPs) including small nuclear RNPs (snRNPs). CBs associate with specific gene loci, which impacts expression and provides a platform for the biogenesis of the nascent transcripts emanating from these genes. Here we report that CBs can associate with the C19MC microRNA (miRNA) gene cluster, which suggests a role for CBs in the biogenesis of animal miRNAs. The machinery involved in the formation of miRNAs includes the Drosha/DGCR8 complex, which processes primary-miRNA to precursor miRNA. Further processing of precursor miRNA by Dicer and other components generates mature miRNA. To test if CBs influence the expression and formation of miRNAs, we examined two representative miRNAs (miR-520 h and let-7a) in conditions that disrupt CBs. CB disruption correlates with alterations in the level of primary and mature miRNA and the let-7a mRNA target, HMGA2. We have also found that the processing of some small CB-specific RNAs (scaRNAs) is directly mediated by the Drosha/DGCR8 complex. ScaRNAs form scaRNPs, which play an important role in snRNP formation. Collectively, our results demonstrate that CBs and the miRNA processing machinery functionally interact and together contribute to the biogenesis of miRNAs and snRNPs.
Collapse
Affiliation(s)
- Madelyn K Logan
- Department of Cell and Molecular Biology, The University of Mississippi Medical Center, Jackson, MS 39216
| | - Douglas M McLaurin
- Department of Cell and Molecular Biology, The University of Mississippi Medical Center, Jackson, MS 39216
| | - Michael D Hebert
- Department of Cell and Molecular Biology, The University of Mississippi Medical Center, Jackson, MS 39216
| |
Collapse
|
21
|
Luo L, Ando S, Sakamoto Y, Suzuki T, Takahashi H, Ishibashi N, Kojima S, Kurihara D, Higashiyama T, Yamamoto KT, Matsunaga S, Machida C, Sasabe M, Machida Y. The formation of perinucleolar bodies is important for normal leaf development and requires the zinc-finger DNA-binding motif in Arabidopsis ASYMMETRIC LEAVES2. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 101:1118-1134. [PMID: 31639235 PMCID: PMC7155070 DOI: 10.1111/tpj.14579] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 09/30/2019] [Accepted: 10/08/2019] [Indexed: 05/27/2023]
Abstract
In Arabidopsis, the ASYMMETRIC LEAVES2 (AS2) protein plays a key role in the formation of flat symmetric leaves via direct repression of the abaxial gene ETT/ARF3. AS2 encodes a plant-specific nuclear protein that contains the AS2/LOB domain, which includes a zinc-finger (ZF) motif that is conserved in the AS2/LOB family. We have shown that AS2 binds to the coding DNA of ETT/ARF3, which requires the ZF motif. AS2 is co-localized with AS1 in perinucleolar bodies (AS2 bodies). To identify the amino acid signals in AS2 required for formation of AS2 bodies and function(s) in leaf formation, we constructed recombinant DNAs that encoded mutant AS2 proteins fused to yellow fluorescent protein. We examined the subcellular localization of these proteins in cells of cotyledons and leaf primordia of transgenic plants and cultured cells. The amino acid signals essential for formation of AS2 bodies were located within and adjacent to the ZF motif. Mutant AS2 that failed to form AS2 bodies also failed to rescue the as2-1 mutation. Our results suggest the importance of the formation of AS2 bodies and the nature of interactions of AS2 with its target DNA and nucleolar factors including NUCLEOLIN1. The partial overlap of AS2 bodies with perinucleolar chromocenters with condensed ribosomal RNA genes implies a correlation between AS2 bodies and the chromatin state. Patterns of AS2 bodies in cells during interphase and mitosis in leaf primordia were distinct from those in cultured cells, suggesting that the formation and distribution of AS2 bodies are developmentally modulated in plants.
Collapse
Affiliation(s)
- Lilan Luo
- Division of Biological ScienceGraduate School of ScienceNagoya UniversityNagoyaAichi464‐8602Japan
- Present address:
Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing100101China
| | - Sayuri Ando
- Graduate School of Bioscience and BiotechnologyChubu UniversityKasugaiAichi487‐8501Japan
| | - Yuki Sakamoto
- Department of Applied Biological ScienceFaculty of Science and TechnologyTokyo University of ScienceNodaChiba278‐8510Japan
- Department of Biological SciencesGraduate School of ScienceOsaka University1‐1 Machikaneyama‐choToyonakaOsaka560‐0043Japan
| | - Takanori Suzuki
- Division of Biological ScienceGraduate School of ScienceNagoya UniversityNagoyaAichi464‐8602Japan
- Central Research InstituteIshihara Sangyo Kaisha, Ltd.2‐3‐1 Nishi‐ShibukawaKusatsuShiga525‐0025Japan
| | - Hiro Takahashi
- Graduate School of Medical SciencesKanazawa UniversityKakuma‐machiKanazawaIshikawa920‐1192Japan
| | - Nanako Ishibashi
- Division of Biological ScienceGraduate School of ScienceNagoya UniversityNagoyaAichi464‐8602Japan
| | - Shoko Kojima
- Graduate School of Bioscience and BiotechnologyChubu UniversityKasugaiAichi487‐8501Japan
| | - Daisuke Kurihara
- JST, PRESTOFuro‐cho, Chikusa‐kuNagoyaAichi464‐8601Japan
- Institute of Transformative Bio‐Molecules (ITbM)Nagoya UniversityFuro‐cho, Chiku00sa‐kuNagoyaAichi464‐8601Japan
| | - Tetsuya Higashiyama
- Division of Biological ScienceGraduate School of ScienceNagoya UniversityNagoyaAichi464‐8602Japan
- Institute of Transformative Bio‐Molecules (ITbM)Nagoya UniversityFuro‐cho, Chiku00sa‐kuNagoyaAichi464‐8601Japan
- Department of Biological SciencesGraduate School of ScienceUniversity of Tokyo7‐3‐1 Hongo, Bukyo‐kuTokyo113‐0033Japan
| | - Kotaro T. Yamamoto
- Division of Biological SciencesFaculty of ScienceHokkaido UniversitySapporo060‐0810Japan
| | - Sachihiro Matsunaga
- Department of Applied Biological ScienceFaculty of Science and TechnologyTokyo University of ScienceNodaChiba278‐8510Japan
| | - Chiyoko Machida
- Graduate School of Bioscience and BiotechnologyChubu UniversityKasugaiAichi487‐8501Japan
| | - Michiko Sasabe
- Department of BiologyFaculty of Agriculture and Life ScienceHirosaki University3 Bunkyo‐choHirosaki036‐8561Japan
| | - Yasunori Machida
- Division of Biological ScienceGraduate School of ScienceNagoya UniversityNagoyaAichi464‐8602Japan
| |
Collapse
|
22
|
Moreno-Castro C, Prieto-Sánchez S, Sánchez-Hernández N, Hernández-Munain C, Suñé C. Role for the splicing factor TCERG1 in Cajal body integrity and snRNP assembly. J Cell Sci 2019; 132:jcs.232728. [PMID: 31636114 DOI: 10.1242/jcs.232728] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Accepted: 10/11/2019] [Indexed: 12/29/2022] Open
Abstract
Cajal bodies are nuclear organelles involved in the nuclear phase of small nuclear ribonucleoprotein (snRNP) biogenesis. In this study, we identified the splicing factor TCERG1 as a coilin-associated factor that is essential for Cajal body integrity. Knockdown of TCERG1 disrupts the localization of the components of Cajal bodies, including coilin and NOLC1, with coilin being dispersed in the nucleoplasm into numerous small foci, without affecting speckles, gems or the histone locus body. Furthermore, the depletion of TCERG1 affects the recruitment of Sm proteins to uridine-rich small nuclear RNAs (snRNAs) to form the mature core snRNP. Taken together, the results of this study suggest that TCERG1 plays an important role in Cajal body formation and snRNP biogenesis.
Collapse
Affiliation(s)
- Cristina Moreno-Castro
- Department of Molecular Biology, Institute of Parasitology and Biomedicine "López-Neyra" (IPBLN-CSIC), PTS, 18016 Granada, Spain
| | - Silvia Prieto-Sánchez
- Department of Molecular Biology, Institute of Parasitology and Biomedicine "López-Neyra" (IPBLN-CSIC), PTS, 18016 Granada, Spain
| | - Noemí Sánchez-Hernández
- Department of Molecular Biology, Institute of Parasitology and Biomedicine "López-Neyra" (IPBLN-CSIC), PTS, 18016 Granada, Spain
| | - Cristina Hernández-Munain
- Department of Cell Biology and Immunology, Institute of Parasitology and Biomedicine "López-Neyra" (IPBLN-CSIC), PTS, 18016 Granada, Spain
| | - Carlos Suñé
- Department of Molecular Biology, Institute of Parasitology and Biomedicine "López-Neyra" (IPBLN-CSIC), PTS, 18016 Granada, Spain
| |
Collapse
|
23
|
Woo WK, Dzaki N, Thangadurai S, Azzam G. Ectopic miR-975 induces CTP synthase directed cell proliferation and differentiation in Drosophila melanogaster. Sci Rep 2019; 9:6096. [PMID: 30988367 PMCID: PMC6465261 DOI: 10.1038/s41598-019-42369-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Accepted: 03/25/2019] [Indexed: 11/16/2022] Open
Abstract
CTP synthase (CTPSyn) is an essential metabolic enzyme, synthesizing precursors required for nucleotides and phospholipids production. Previous studies have also shown that CTPSyn is elevated in various cancers. In many organisms, CTPSyn compartmentalizes into filaments called cytoophidia. In Drosophila melanogaster, only its isoform C (CTPSynIsoC) forms cytoophidia. In the fruit fly's testis, cytoophidia are normally seen in the transit amplification regions close to its apical tip, where the stem-cell niche is located, and development is at its most rapid. Here, we report that CTPSynIsoC overexpression causes the lengthening of cytoophidia throughout the entirety of the testicular body. A bulging apical tip is found in approximately 34% of males overexpressing CTPSynIsoC. Immunostaining shows that this bulged phenotype is most likely due to increased numbers of both germline cells and spermatocytes. Through a microRNA (miRNA) overexpression screen, we found that ectopic miR-975 concurrently increases both the expression levels of CTPSyn and the length of its cytoophidia. The bulging testes phenotype was also recovered at a penetration of approximately 20%. However, qPCR assays reveal that CTPSynIsoC and miR-975 overexpression each provokes a differential response in expression of a number of cancer-related genes, indicating that the shared CTPSyn upregulation seen in either case is likely the cause of observed testicular overgrowth. This study presents the first instance of consequences of miRNA-asserted regulation upon CTPSyn in D. melanogaster, and further reaffirms the enzyme's close ties to germline cells overgrowth.
Collapse
Affiliation(s)
- Wai Kan Woo
- School of Biological Sciences, Universiti Sains Malaysia, 11800, Penang, Malaysia
| | - Najat Dzaki
- School of Biological Sciences, Universiti Sains Malaysia, 11800, Penang, Malaysia
| | | | - Ghows Azzam
- School of Biological Sciences, Universiti Sains Malaysia, 11800, Penang, Malaysia.
| |
Collapse
|
24
|
Patrón LA, Nagatomo K, Eves DT, Imad M, Young K, Torvund M, Guo X, Rogers GC, Zinsmaier KE. Cul4 ubiquitin ligase cofactor DCAF12 promotes neurotransmitter release and homeostatic plasticity. J Cell Biol 2019; 218:993-1010. [PMID: 30670470 PMCID: PMC6400570 DOI: 10.1083/jcb.201805099] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 11/13/2018] [Accepted: 12/20/2018] [Indexed: 12/20/2022] Open
Abstract
Patrón et al. show that presynaptic Drosophila DCAF12 is required for neurotransmitter release and homeostatic synaptic plasticity at neuromuscular junctions. Postsynaptic nuclear DCAF12 controls the expression of glutamate receptor IIA subunits in cooperation with Cullin4 ubiquitin ligase. We genetically characterized the synaptic role of the Drosophila homologue of human DCAF12, a putative cofactor of Cullin4 (Cul4) ubiquitin ligase complexes. Deletion of Drosophila DCAF12 impairs larval locomotion and arrests development. At larval neuromuscular junctions (NMJs), DCAF12 is expressed presynaptically in synaptic boutons, axons, and nuclei of motor neurons. Postsynaptically, DCAF12 is expressed in muscle nuclei and facilitates Cul4-dependent ubiquitination. Genetic experiments identified several mechanistically independent functions of DCAF12 at larval NMJs. First, presynaptic DCAF12 promotes evoked neurotransmitter release. Second, postsynaptic DCAF12 negatively controls the synaptic levels of the glutamate receptor subunits GluRIIA, GluRIIC, and GluRIID. The down-regulation of synaptic GluRIIA subunits by nuclear DCAF12 requires Cul4. Third, presynaptic DCAF12 is required for the expression of synaptic homeostatic potentiation. We suggest that DCAF12 and Cul4 are critical for normal synaptic function and plasticity at larval NMJs.
Collapse
Affiliation(s)
- Lilian A Patrón
- Department of Neuroscience, University of Arizona, Tucson, AZ.,Graduate Interdisciplinary Program in Neuroscience, University of Arizona, Tucson, AZ
| | - Kei Nagatomo
- Department of Neuroscience, University of Arizona, Tucson, AZ
| | | | - Mays Imad
- Department of Neuroscience, University of Arizona, Tucson, AZ
| | - Kimberly Young
- Department of Neuroscience, University of Arizona, Tucson, AZ
| | - Meaghan Torvund
- Department of Neuroscience, University of Arizona, Tucson, AZ.,Graduate Interdisciplinary Program in Neuroscience, University of Arizona, Tucson, AZ
| | - Xiufang Guo
- Department of Neuroscience, University of Arizona, Tucson, AZ
| | - Gregory C Rogers
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ.,Department of Cellular and Molecular Medicine, University of Arizona, Tucson, AZ
| | - Konrad E Zinsmaier
- Department of Neuroscience, University of Arizona, Tucson, AZ .,Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ
| |
Collapse
|
25
|
Deryusheva S, Gall JG. scaRNAs and snoRNAs: Are they limited to specific classes of substrate RNAs? RNA (NEW YORK, N.Y.) 2019; 25:17-22. [PMID: 30301832 PMCID: PMC6298559 DOI: 10.1261/rna.068593.118] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2018] [Accepted: 10/07/2018] [Indexed: 05/28/2023]
Abstract
Posttranscriptional modifications of rRNA occur in the nucleolus where rRNA modification guide RNAs, or snoRNAs, concentrate. On the other hand, scaRNAs, the modification guide RNAs for spliceosomal snRNAs, concentrate in the Cajal body (CB). It is generally assumed, therefore, that snRNAs must accumulate in CBs to be modified by scaRNAs. Here we demonstrate that the evidence for the latter postulate is not consistent. In the nucleus, scaRNA localization is not limited to CBs. Furthermore, canonical scaRNAs can modify rRNAs. We suggest that the conventional view that scaRNAs function only in the CB needs revision.
Collapse
MESH Headings
- Animals
- Base Sequence
- Coiled Bodies/metabolism
- HeLa Cells
- Humans
- Nucleic Acid Conformation
- RNA Processing, Post-Transcriptional
- RNA, Ribosomal/chemistry
- RNA, Ribosomal/genetics
- RNA, Ribosomal/metabolism
- RNA, Small Nuclear/chemistry
- RNA, Small Nuclear/genetics
- RNA, Small Nuclear/metabolism
- RNA, Small Nucleolar/chemistry
- RNA, Small Nucleolar/genetics
- RNA, Small Nucleolar/metabolism
- Spliceosomes/genetics
- Spliceosomes/metabolism
- Xenopus/genetics
- Xenopus/metabolism
- RNA, Guide, CRISPR-Cas Systems
Collapse
Affiliation(s)
- Svetlana Deryusheva
- Department of Embryology, Carnegie Institution for Science, Baltimore, Maryland 21218, USA
| | - Joseph G Gall
- Department of Embryology, Carnegie Institution for Science, Baltimore, Maryland 21218, USA
| |
Collapse
|
26
|
Aquilina B, Cauchi RJ. Modelling motor neuron disease in fruit flies: Lessons from spinal muscular atrophy. J Neurosci Methods 2018; 310:3-11. [DOI: 10.1016/j.jneumeth.2018.04.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2017] [Revised: 04/06/2018] [Accepted: 04/07/2018] [Indexed: 12/25/2022]
|
27
|
Mendiratta S, Gatto A, Almouzni G. Histone supply: Multitiered regulation ensures chromatin dynamics throughout the cell cycle. J Cell Biol 2018; 218:39-54. [PMID: 30257851 PMCID: PMC6314538 DOI: 10.1083/jcb.201807179] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Revised: 09/05/2018] [Accepted: 09/12/2018] [Indexed: 12/14/2022] Open
Abstract
Mendiratta et al. review the interplay between the different regulatory layers that affect the transcription and dynamics of distinct histone H3 variants along the cell cycle. As the building blocks of chromatin, histones are central to establish and maintain particular chromatin states associated with given cell fates. Importantly, histones exist as distinct variants whose expression and incorporation into chromatin are tightly regulated during the cell cycle. During S phase, specialized replicative histone variants ensure the bulk of the chromatinization of the duplicating genome. Other non-replicative histone variants deposited throughout the cell cycle at specific loci use pathways uncoupled from DNA synthesis. Here, we review the particular dynamics of expression, cellular transit, assembly, and disassembly of replicative and non-replicative forms of the histone H3. Beyond the role of histone variants in chromatin dynamics, we review our current knowledge concerning their distinct regulation to control their expression at different levels including transcription, posttranscriptional processing, and protein stability. In light of this unique regulation, we highlight situations where perturbations in histone balance may lead to cellular dysfunction and pathologies.
Collapse
Affiliation(s)
- Shweta Mendiratta
- Institut Curie, Paris Sciences et Lettres Research University, Centre National de la Recherche Scientifique, UMR3664, Equipe Labellisée Ligue contre le Cancer, Paris, France.,Sorbonne Universités, Université Pierre et Marie Curie Paris 06, Centre National de la Recherche Scientifique, UMR3664, Paris, France
| | - Alberto Gatto
- Institut Curie, Paris Sciences et Lettres Research University, Centre National de la Recherche Scientifique, UMR3664, Equipe Labellisée Ligue contre le Cancer, Paris, France.,Sorbonne Universités, Université Pierre et Marie Curie Paris 06, Centre National de la Recherche Scientifique, UMR3664, Paris, France
| | - Genevieve Almouzni
- Institut Curie, Paris Sciences et Lettres Research University, Centre National de la Recherche Scientifique, UMR3664, Equipe Labellisée Ligue contre le Cancer, Paris, France .,Sorbonne Universités, Université Pierre et Marie Curie Paris 06, Centre National de la Recherche Scientifique, UMR3664, Paris, France
| |
Collapse
|
28
|
Arias Escayola D, Neugebauer KM. Dynamics and Function of Nuclear Bodies during Embryogenesis. Biochemistry 2018; 57:2462-2469. [PMID: 29473743 DOI: 10.1021/acs.biochem.7b01262] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Nuclear bodies are RNA-rich membraneless organelles in the cell nucleus that concentrate specific sets of nuclear proteins and RNA-protein complexes. Nuclear bodies such as the nucleolus, Cajal body (CB), and the histone locus body (HLB) concentrate factors required for nuclear steps of RNA processing. Formation of these nuclear bodies occurs on genomic loci and is frequently associated with active sites of transcription. Whether nuclear body formation is dependent on a particular gene element, an active process such as transcription, or the nascent RNA present at gene loci is a topic of debate. Recently, this question has been addressed through studies in model organisms and their embryos. The switch from maternally provided RNA and protein to zygotic gene products in early embryos has been well characterized in a variety of organisms. This process, termed maternal-to-zygotic transition, provides an excellent model for studying formation of nuclear bodies before, during, and after the transcriptional activation of the zygotic genome. Here, we review findings in embryos that reveal key principles in the study of the formation and function of nucleoli, CBs, and HLBs. We propose that while particular gene elements may contribute to formation of these nuclear bodies, active transcription promotes maturation of nuclear bodies and efficient RNA processing within them.
Collapse
Affiliation(s)
- Dahyana Arias Escayola
- Molecular Biophysics and Biochemistry , Yale University , New Haven , Connecticut 06520-8114 , United States
| | - Karla M Neugebauer
- Molecular Biophysics and Biochemistry , Yale University , New Haven , Connecticut 06520-8114 , United States
| |
Collapse
|
29
|
Chen Z, Gui B, Zhang Y, Xie G, Li W, Liu S, Xu B, Wu C, He L, Yang J, Yi X, Yang X, Sun L, Liang J, Shang Y. Identification of a 35S U4/U6.U5 tri-small nuclear ribonucleoprotein (tri-snRNP) complex intermediate in spliceosome assembly. J Biol Chem 2017; 292:18113-18128. [PMID: 28878014 DOI: 10.1074/jbc.m117.797357] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Revised: 08/28/2017] [Indexed: 11/06/2022] Open
Abstract
The de novo assembly and post-splicing reassembly of the U4/U6.U5 tri-snRNP remain to be investigated. We report here that ZIP, a protein containing a CCCH-type zinc finger and a G-patch domain, as characterized by us previously, regulates pre-mRNA splicing independent of RNA binding. We found that ZIP physically associates with the U4/U6.U5 tri-small nuclear ribonucleoprotein (tri-snRNP). Remarkably, the ZIP-containing tri-snRNP, which has a sedimentation coefficient of ∼35S, is a tri-snRNP that has not been described previously. We also found that the 35S tri-snRNP contains hPrp24, indicative of a state in which the U4/U6 di-snRNP is integrating with the U5 snRNP. We found that the 35S tri-snRNP is enriched in the Cajal body, indicating that it is an assembly intermediate during 25S tri-snRNP maturation. We showed that the 35S tri-snRNP also contains hPrp43, in which ATPase/RNA helicase activities are stimulated by ZIP. Our study identified, for the first time, a tri-snRNP intermediate, shedding new light on the de novo assembly and recycling of the U4/U6.U5 tri-snRNP.
Collapse
Affiliation(s)
- Zhe Chen
- From the Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Bin Gui
- From the Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Yu Zhang
- From the Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Guojia Xie
- From the Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Wanjin Li
- From the Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Shumeng Liu
- From the Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Bosen Xu
- From the Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Chongyang Wu
- From the Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Lin He
- From the Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Jianguo Yang
- From the Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Xia Yi
- From the Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Xiaohan Yang
- From the Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Luyang Sun
- From the Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Jing Liang
- From the Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Yongfeng Shang
- From the Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China, .,the Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, China, and.,the Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Capital Medical University, Beijing 100069, China
| |
Collapse
|
30
|
Rode S, Ohm H, Zipfel J, Rumpf S. The spliceosome-associated protein Mfap1 binds to VCP in Drosophila. PLoS One 2017; 12:e0183733. [PMID: 28837687 PMCID: PMC5570293 DOI: 10.1371/journal.pone.0183733] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Accepted: 08/09/2017] [Indexed: 12/14/2022] Open
Abstract
Posttranscriptional regulation of gene expression contributes to many developmental transitions. Previously, we found that the AAA chaperone Valosin-Containing Protein (VCP) regulates ecdysone-dependent dendrite pruning of Drosophila class IV dendritic arborization (c4da) neurons via an effect on RNA metabolism. In a search for RNA binding proteins associated with VCP, we identified the spliceosome-associated protein Mfap1, a component of the tri-snRNP complex. Mfap1 is a nucleolar protein in neurons and its levels are regulated by VCP. Mfap1 binds to VCP and TDP-43, a disease-associated RNA-binding protein. via distinct regions in its N- and C-terminal halfs. Similar to vcp mutations, Mfap1 overexpression causes c4da neuron dendrite pruning defects and mislocalization of TDP-43 in these cells, but genetic analyses show that Mfap1 is not a crucial VCP target during dendrite pruning. Finally, rescue experiments with a lethal mfap1 mutant show that the VCP binding region is not essential for Mfap1 function, but may act to increase its stability or activity.
Collapse
Affiliation(s)
- Sandra Rode
- Institute for Neurobiology, University of Münster, Badestrasse 9, Münster, Germany
| | - Henrike Ohm
- Institute for Neurobiology, University of Münster, Badestrasse 9, Münster, Germany
| | - Jaqueline Zipfel
- Institute for Neurobiology, University of Münster, Badestrasse 9, Münster, Germany
| | - Sebastian Rumpf
- Institute for Neurobiology, University of Münster, Badestrasse 9, Münster, Germany
- * E-mail:
| |
Collapse
|
31
|
Epstein-Barr virus-induced up-regulation of TCAB1 is involved in the DNA damage response in nasopharyngeal carcinoma. Sci Rep 2017; 7:3218. [PMID: 28607398 PMCID: PMC5468285 DOI: 10.1038/s41598-017-03156-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 04/25/2017] [Indexed: 02/05/2023] Open
Abstract
Telomerase Cajal body protein 1 (TCAB1), which is involved in Cajal body maintenance, telomere elongation and ribonucleoprotein biogenesis, has been linked to cancer predisposition, including nasopharyngeal carcinoma (NPC), due to its oncogenic properties. However, there are no specific reports to date on the functional relevance of TCAB1 and Epstein–Barr virus (EBV), which is considered to be a risk factor for NPC. In this study, we first examined NPC clinical tissues and found a notable overexpression of TCAB1 in EBV-positive specimens. Secondly, on a cellular level, we also observed that TCAB1 expression rose gradually along with the increased duration of EBV exposure in NPC cell lines. Additionally, EBV infection promoted cell proliferation and telomerase activity, but the activation was significantly inhibited after TCAB1 knockdown. Moreover, depletion of TCAB1 caused both cell cycle arrest and apoptosis, and suppressed the activation of ataxia telangiectasia and Rad3 related protein (ATR) induced by EBV, resulting in accumulation of DNA damage. Taken together, we here demonstrate that up-regulated expression of TCAB1, induced by EBV in the development of NPC, is involved in stimulating telomerase activity and regulating the DNA damage response within the context of EBV infection.
Collapse
|
32
|
Love AJ, Yu C, Petukhova NV, Kalinina NO, Chen J, Taliansky ME. Cajal bodies and their role in plant stress and disease responses. RNA Biol 2017; 14:779-790. [PMID: 27726481 PMCID: PMC5519230 DOI: 10.1080/15476286.2016.1243650] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 09/19/2016] [Accepted: 09/27/2016] [Indexed: 12/11/2022] Open
Abstract
Cajal bodies (CBs) are distinct sub-nuclear structures that are present in eukaryotic living cells and are often associated with the nucleolus. CBs play important roles in RNA metabolism and formation of RNPs involved in transcription, splicing, ribosome biogenesis, and telomere maintenance. Besides these primary roles, CBs appear to be involved in additional functions that may not be directly related to RNA metabolism and RNP biogenesis. In this review, we assess possible roles of plant CBs in RNA regulatory pathways such as nonsense-mediated mRNA decay and RNA silencing. We also summarize recent progress and discuss new non-canonical functions of plant CBs in responses to stress and disease. It is hypothesized that CBs can regulate these responses via their interaction with poly(ADP ribose)polymerase (PARP), which is known to play an important role in various physiological processes including responses to biotic and abiotic stresses. It is suggested that CBs and their components modify PARP activities and functions.
Collapse
Affiliation(s)
- Andrew J. Love
- Cell and Molecular Sciences, James Hutton Institute, Invergowrie, Dundee, UK
| | - Chulang Yu
- State Key Laboratory Breeding Base for Sustainable Pest and Disease Control, Key Laboratory of Biotechnology in Plant Protection of MOA and Zhejiang Province, Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | | | - Natalia O. Kalinina
- A.N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Leninskie Gory, Moscow, Russia
| | - Jianping Chen
- State Key Laboratory Breeding Base for Sustainable Pest and Disease Control, Key Laboratory of Biotechnology in Plant Protection of MOA and Zhejiang Province, Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Michael E. Taliansky
- Cell and Molecular Sciences, James Hutton Institute, Invergowrie, Dundee, UK
- State Key Laboratory Breeding Base for Sustainable Pest and Disease Control, Key Laboratory of Biotechnology in Plant Protection of MOA and Zhejiang Province, Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| |
Collapse
|
33
|
Sawyer IA, Hager GL, Dundr M. Specific genomic cues regulate Cajal body assembly. RNA Biol 2017; 14:791-803. [PMID: 27715441 PMCID: PMC5519236 DOI: 10.1080/15476286.2016.1243648] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Revised: 09/06/2016] [Accepted: 09/27/2016] [Indexed: 02/07/2023] Open
Abstract
The assembly of specialized sub-nuclear microenvironments known as nuclear bodies (NBs) is important for promoting efficient nuclear function. In particular, the Cajal body (CB), a prominent NB that facilitates spliceosomal snRNP biogenesis, assembles in response to genomic cues. Here, we detail the factors that regulate CB assembly and structural maintenance. These include the importance of transcription at nucleating gene loci, the grouping of these genes on human chromosomes 1, 6 and 17, as well as cell cycle and biochemical regulation of CB protein function. We also speculate on the correlation between CB formation and RNA splicing levels in neurons and cancer. The timing and location of these specific molecular events is critical to CB assembly and its contribution to genome function. However, further work is required to explore the emerging biophysical characteristics of CB assembly and the impact upon subsequent genome reorganization.
Collapse
Affiliation(s)
- Iain A. Sawyer
- Department of Cell Biology, Rosalind Franklin University of Medicine & Science, Chicago Medical School, North Chicago, IL, USA
- Laboratory of Receptor Biology and Gene Expression, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Gordon L. Hager
- Laboratory of Receptor Biology and Gene Expression, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Miroslav Dundr
- Department of Cell Biology, Rosalind Franklin University of Medicine & Science, Chicago Medical School, North Chicago, IL, USA
| |
Collapse
|
34
|
Di Giorgio ML, Esposito A, Maccallini P, Micheli E, Bavasso F, Gallotta I, Vernì F, Feiguin F, Cacchione S, McCabe BD, Di Schiavi E, Raffa GD. WDR79/TCAB1 plays a conserved role in the control of locomotion and ameliorates phenotypic defects in SMA models. Neurobiol Dis 2017; 105:42-50. [PMID: 28502804 DOI: 10.1016/j.nbd.2017.05.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Revised: 04/19/2017] [Accepted: 05/10/2017] [Indexed: 12/22/2022] Open
Abstract
SMN (Survival Motor Neuron) deficiency is the predominant cause of spinal muscular atrophy (SMA), a severe neurodegenerative disorder that can lead to progressive paralysis and death. Although SMN is required in every cell for proper RNA metabolism, the reason why its loss is especially critical in the motor system is still unclear. SMA genetic models have been employed to identify several modifiers that can ameliorate the deficits induced by SMN depletion. Here we focus on WDR79/TCAB1, a protein important for the biogenesis of several RNA species that has been shown to physically interact with SMN in human cells. We show that WDR79 depletion results in locomotion defects in both Drosophila and Caenorhabditis elegans similar to those elicited by SMN depletion. Consistent with this observation, we find that SMN overexpression rescues the WDR79 loss-of-function phenotype in flies. Most importantly, we also found that WDR79 overexpression ameliorates the locomotion defects induced by SMN depletion in both flies and worms. Our results collectively suggest that WDR79 and SMN play evolutionarily conserved cooperative functions in the nervous system and suggest that WDR79/TCAB1 may have the potential to modify SMA pathogenesis.
Collapse
Affiliation(s)
- Maria Laura Di Giorgio
- Istituto Pasteur-Fondazione Cenci Bolognetti, Dipartimento di Biologia e Biotecnologie, Sapienza Università di Roma, Rome, Italy
| | | | - Paolo Maccallini
- Istituto Pasteur-Fondazione Cenci Bolognetti, Dipartimento di Biologia e Biotecnologie, Sapienza Università di Roma, Rome, Italy
| | - Emanuela Micheli
- Istituto Pasteur-Fondazione Cenci Bolognetti, Dipartimento di Biologia e Biotecnologie, Sapienza Università di Roma, Rome, Italy
| | - Francesca Bavasso
- Istituto Pasteur-Fondazione Cenci Bolognetti, Dipartimento di Biologia e Biotecnologie, Sapienza Università di Roma, Rome, Italy
| | - Ivan Gallotta
- Institute of Genetics and Biophysics - ABT, CNR, Naples, Italy
| | - Fiammetta Vernì
- Istituto Pasteur-Fondazione Cenci Bolognetti, Dipartimento di Biologia e Biotecnologie, Sapienza Università di Roma, Rome, Italy
| | - Fabian Feiguin
- International Centre for Genetic Engineering and Biotechnology, Trieste, Italy
| | - Stefano Cacchione
- Istituto Pasteur-Fondazione Cenci Bolognetti, Dipartimento di Biologia e Biotecnologie, Sapienza Università di Roma, Rome, Italy
| | | | - Elia Di Schiavi
- Institute of Genetics and Biophysics - ABT, CNR, Naples, Italy; Institute of Bioscience and Bioresources, CNR, Naples, Italy
| | - Grazia Daniela Raffa
- Istituto Pasteur-Fondazione Cenci Bolognetti, Dipartimento di Biologia e Biotecnologie, Sapienza Università di Roma, Rome, Italy.
| |
Collapse
|
35
|
D’Brot A, Kurtz P, Regan E, Jakubowski B, Abrams JM. A platform for interrogating cancer-associated p53 alleles. Oncogene 2017; 36:286-291. [PMID: 26996664 PMCID: PMC5031501 DOI: 10.1038/onc.2016.48] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Revised: 01/06/2016] [Accepted: 01/19/2016] [Indexed: 12/13/2022]
Abstract
p53 is the most frequently mutated gene in human cancer. Compelling evidence argues that full transformation involves loss of growth suppression encoded by wild-type p53 together with poorly understood oncogenic activity encoded by missense mutations. Furthermore, distinguishing disease alleles from natural polymorphisms is an important clinical challenge. To interrogate the genetic activity of human p53 variants, we leveraged the Drosophila model as an in vivo platform. We engineered strains that replace the fly p53 gene with human alleles, producing a collection of stocks that are, in effect, 'humanized' for p53 variants. Like the fly counterpart, human p53 transcriptionally activated a biosensor and induced apoptosis after DNA damage. However, all humanized strains representing common alleles found in cancer patients failed to complement in these assays. Surprisingly, stimulus-dependent activation of hp53 occurred without stabilization, demonstrating that these two processes can be uncoupled. Like its fly counterpart, hp53 formed prominent nuclear foci in germline cells but cancer-associated p53 variants did not. Moreover, these same mutant alleles disrupted hp53 foci and inhibited biosensor activity, suggesting that these properties are functionally linked. Together these findings establish a functional platform for interrogating human p53 alleles and suggest that simple phenotypes could be used to stratify disease variants.
Collapse
Affiliation(s)
- Alejandro D’Brot
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Paula Kurtz
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Erin Regan
- Department of Physical Therapy, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | | | - John M Abrams
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| |
Collapse
|
36
|
Duronio RJ, Marzluff WF. Coordinating cell cycle-regulated histone gene expression through assembly and function of the Histone Locus Body. RNA Biol 2017; 14:726-738. [PMID: 28059623 DOI: 10.1080/15476286.2016.1265198] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
Metazoan replication-dependent (RD) histone genes encode the only known cellular mRNAs that are not polyadenylated. These mRNAs end instead in a conserved stem-loop, which is formed by an endonucleolytic cleavage of the pre-mRNA. The genes for all 5 histone proteins are clustered in all metazoans and coordinately regulated with high levels of expression during S phase. Production of histone mRNAs occurs in a nuclear body called the Histone Locus Body (HLB), a subdomain of the nucleus defined by a concentration of factors necessary for histone gene transcription and pre-mRNA processing. These factors include the scaffolding protein NPAT, essential for histone gene transcription, and FLASH and U7 snRNP, both essential for histone pre-mRNA processing. Histone gene expression is activated by Cyclin E/Cdk2-mediated phosphorylation of NPAT at the G1-S transition. The concentration of factors within the HLB couples transcription with pre-mRNA processing, enhancing the efficiency of histone mRNA biosynthesis.
Collapse
Affiliation(s)
- Robert J Duronio
- a Department of Biology , University of North Carolina , Chapel Hill , NC , USA.,b Department of Genetics , University of North Carolina , Chapel Hill , NC , USA.,c Integrative Program for Biological and Genome Sciences , University of North Carolina , Chapel Hill , NC , USA.,d Lineberger Comprehensive Cancer Center , University of North Carolina , Chapel Hill , NC , USA
| | - William F Marzluff
- a Department of Biology , University of North Carolina , Chapel Hill , NC , USA.,c Integrative Program for Biological and Genome Sciences , University of North Carolina , Chapel Hill , NC , USA.,d Lineberger Comprehensive Cancer Center , University of North Carolina , Chapel Hill , NC , USA.,e Department of Biochemistry and Biophysics , University of North Carolina , Chapel Hill , NC , USA
| |
Collapse
|
37
|
Kulikova T, Khodyuchenko T, Petrov Y, Krasikova A. Low-voltage scanning electron microscopy study of lampbrush chromosomes and nuclear bodies in avian and amphibian oocytes. Sci Rep 2016; 6:36878. [PMID: 27857188 PMCID: PMC5114574 DOI: 10.1038/srep36878] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Accepted: 10/24/2016] [Indexed: 12/01/2022] Open
Abstract
Nucleus is a highly compartmentalized part of the cell where the key processes of genome functionality are realized through the formation of non-membranous nuclear domains. Physically nuclear domains appear as liquid droplets with different viscosity stably maintained throughout the interphase or during the long diplotene stage of meiosis. Since nuclear body surface represents boundary between two liquid phases, the ultrastructural surface topography of nuclear domains is of an outstanding interest. The aim of this study was to examine ultrathin surface topography of the amphibian and avian oocyte nuclear structures such as lampbrush chromosomes, nucleoli, histone-locus bodies, Cajal body-like bodies, and the interchromatin granule clusters via low-voltage scanning electron microscopy. Our results demonstrate that nuclear bodies with similar molecular composition may differ dramatically in the surface topography and vice versa, nuclear bodies that do not share common molecular components may possess similar topographical characteristics. We also have analyzed surface distribution of particular nuclear antigens (double stranded DNA, coilin and splicing snRNA) using indirect immunogold labeling with subsequent secondary electron detection of gold nanoparticles. We suggest that ultrastructural surface morphology reflects functional status of a nuclear body.
Collapse
Affiliation(s)
| | | | - Yuri Petrov
- Saint-Petersburg State University, Saint-Petersburg, Russia
| | - Alla Krasikova
- Saint-Petersburg State University, Saint-Petersburg, Russia
| |
Collapse
|
38
|
Identification of Coilin Mutants in a Screen for Enhanced Expression of an Alternatively Spliced GFP Reporter Gene in Arabidopsis thaliana. Genetics 2016; 203:1709-20. [PMID: 27317682 PMCID: PMC4981272 DOI: 10.1534/genetics.116.190751] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Accepted: 06/09/2016] [Indexed: 02/02/2023] Open
Abstract
Coilin is a marker protein for subnuclear organelles known as Cajal bodies, which are sites of various RNA metabolic processes including the biogenesis of spliceosomal small nuclear ribonucleoprotein particles. Through self-associations and interactions with other proteins and RNA, coilin provides a structural scaffold for Cajal body formation. However, despite a conspicuous presence in Cajal bodies, most coilin is dispersed in the nucleoplasm and expressed in cell types that lack these organelles. The molecular function of coilin, particularly of the substantial nucleoplasmic fraction, remains uncertain. We identified coilin loss-of-function mutations in a genetic screen for mutants showing either reduced or enhanced expression of an alternatively spliced GFP reporter gene in Arabidopsis thaliana The coilin mutants feature enhanced GFP fluorescence and diminished Cajal bodies compared with wild-type plants. The amount of GFP protein is several-fold higher in the coilin mutants owing to elevated GFP transcript levels and more efficient splicing to produce a translatable GFP mRNA. Genome-wide RNA-sequencing data from two distinct coilin mutants revealed a small, shared subset of differentially expressed genes, many encoding stress-related proteins, and, unexpectedly, a trend toward increased splicing efficiency. These results suggest that coilin attenuates splicing and modulates transcription of a select group of genes. The transcriptional and splicing changes observed in coilin mutants are not accompanied by gross phenotypic abnormalities or dramatically altered stress responses, supporting a role for coilin in fine tuning gene expression. Our GFP reporter gene provides a sensitive monitor of coilin activity that will facilitate further investigations into the functions of this enigmatic protein.
Collapse
|
39
|
Tatomer DC, Terzo E, Curry KP, Salzler H, Sabath I, Zapotoczny G, McKay DJ, Dominski Z, Marzluff WF, Duronio RJ. Concentrating pre-mRNA processing factors in the histone locus body facilitates efficient histone mRNA biogenesis. J Cell Biol 2016; 213:557-70. [PMID: 27241916 PMCID: PMC4896052 DOI: 10.1083/jcb.201504043] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Accepted: 04/27/2016] [Indexed: 11/22/2022] Open
Abstract
The histone locus body (HLB) assembles at replication-dependent histone genes and concentrates factors required for histone messenger RNA (mRNA) biosynthesis. FLASH (Flice-associated huge protein) and U7 small nuclear RNP (snRNP) are HLB components that participate in 3' processing of the nonpolyadenylated histone mRNAs by recruiting the endonuclease CPSF-73 to histone pre-mRNA. Using transgenes to complement a FLASH mutant, we show that distinct domains of FLASH involved in U7 snRNP binding, histone pre-mRNA cleavage, and HLB localization are all required for proper FLASH function in vivo. By genetically manipulating HLB composition using mutations in FLASH, mutations in the HLB assembly factor Mxc, or depletion of the variant histone H2aV, we find that failure to concentrate FLASH and/or U7 snRNP in the HLB impairs histone pre-mRNA processing. This failure results in accumulation of small amounts of polyadenylated histone mRNA and nascent read-through transcripts at the histone locus. Thus, the HLB concentrates FLASH and U7 snRNP, promoting efficient histone mRNA biosynthesis and coupling 3' end processing with transcription termination.
Collapse
Affiliation(s)
- Deirdre C Tatomer
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599
| | - Esteban Terzo
- Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, NC 27599
| | - Kaitlin P Curry
- Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, NC 27599
| | - Harmony Salzler
- Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, NC 27599
| | - Ivan Sabath
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC 27599
| | - Grzegorz Zapotoczny
- Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, NC 27599
| | - Daniel J McKay
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599 Integrative Program for Biological and Genome Sciences, University of North Carolina, Chapel Hill, NC 27599 Department of Genetics, University of North Carolina, Chapel Hill, NC 27599
| | - Zbigniew Dominski
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC 27599 Integrative Program for Biological and Genome Sciences, University of North Carolina, Chapel Hill, NC 27599
| | - William F Marzluff
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599 Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, NC 27599 Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC 27599 Integrative Program for Biological and Genome Sciences, University of North Carolina, Chapel Hill, NC 27599 Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599
| | - Robert J Duronio
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599 Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, NC 27599 Integrative Program for Biological and Genome Sciences, University of North Carolina, Chapel Hill, NC 27599 Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599 Department of Genetics, University of North Carolina, Chapel Hill, NC 27599
| |
Collapse
|
40
|
Wang Y, DiMario P. Loss of Drosophila nucleostemin 2 (NS2) blocks nucleolar release of the 60S subunit leading to ribosome stress. Chromosoma 2016; 126:375-388. [PMID: 27150106 DOI: 10.1007/s00412-016-0597-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Revised: 04/18/2016] [Accepted: 04/25/2016] [Indexed: 12/24/2022]
Abstract
Four nucleostemin-like proteins (nucleostemin (NS) 1-4) were identified previously in Drosophila melanogaster. NS1 and NS2 are nucleolar proteins, while NS3 and NS4 are cytoplasmic proteins. We showed earlier that NS1 (homologous to human GNL3) enriches within the granular components (GCs) of Drosophila nucleoli and is required for efficient maturation or nucleolar release of the 60S subunit. Here, we show that NS2 is homologous to the human nucleostemin-like protein, Ngp1 (GNL2), and that endogenous NS2 is expressed in both progenitor and terminally differentiated cell types. Exogenous GFP-NS2 enriched within nucleolar GCs versus endogenous fibrillarin that marked the dense fibrillar components (DFCs). Like NS1, depletion of NS2 in midgut cells blocked the release of the 60S subunit as detected by the accumulation of GFP-RpL11 within nucleoli, and this likely led to the general loss of 60S subunits as shown by immunoblot analyses of RpL23a and RpL34. At the ultrastructural level, nucleoli in midgut cells depleted of NS2 displayed enlarged GCs not only on the nucleolar periphery but interspersed within the DFCs. Depletion of NS2 caused ribosome stress: larval midgut cells displayed prominent autophagy marked by the appearance of autolysosomes containing mCherry-ATG8a and the appearance of rough endoplasmic reticulum (rER)-derived isolation membranes. Larval imaginal wing disc cells depleted of NS2 induced apoptosis as marked by anti-caspase 3 labeling; loss of these progenitor cells resulted in defective adult wings. We conclude that nucleolar proteins NS1 and NS2 have similar but non-overlapping roles in the final maturation or nucleolar release of 60S ribosomal subunits.
Collapse
Affiliation(s)
- Yubo Wang
- Department of Biological Sciences, Louisiana State University, 202 Life Sciences Building, Baton Rouge, LA, 70803-1715, USA
| | - Patrick DiMario
- Department of Biological Sciences, Louisiana State University, 202 Life Sciences Building, Baton Rouge, LA, 70803-1715, USA.
| |
Collapse
|
41
|
Ozawa N, Furuhashi H, Masuko K, Numao E, Makino T, Yano T, Kurata S. Organ identity specification factor WGE localizes to the histone locus body and regulates histone expression to ensure genomic stability in Drosophila. Genes Cells 2016; 21:442-56. [PMID: 27145109 DOI: 10.1111/gtc.12354] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 01/28/2016] [Indexed: 12/19/2022]
Abstract
Over-expression of Winged-Eye (WGE) in the Drosophila eye imaginal disc induces an eye-to-wing transformation. Endogenous WGE is required for organ development, and wge-deficient mutants exhibit growth arrest at the larval stage, suggesting that WGE is critical for normal growth. The function of WGE, however, remains unclear. Here, we analyzed the subcellular localization of WGE to gain insight into its endogenous function. Immunostaining showed that WGE localized to specific nuclear foci called the histone locus body (HLB), an evolutionarily conserved nuclear body required for S phase-specific histone mRNA production. Histone mRNA levels and protein levels in cytosolic fractions were aberrantly up-regulated in wge mutant larva, suggesting a role for WGE in regulating histone gene expression. Genetic analyses showed that wge suppresses position-effect variegation, and that WGE and a HLB component Mute appears to be synergistically involved in heterochromatin formation. Further supporting a role in chromatin regulation, wge-deficient mutants showed derepression of retrotransposons and increased γH2Av signals, a DNA damage marker. These findings suggest that WGE is a component of HLB in Drosophila with a role in heterochromatin formation and transposon silencing. We propose that WGE at HLB contributes to genomic stability and development by regulating heterochromatin structure via histone gene regulation.
Collapse
Affiliation(s)
- Nao Ozawa
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, 980-8578, Japan
| | - Hirofumi Furuhashi
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, 980-8578, Japan
| | - Keita Masuko
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, 980-8578, Japan
| | - Eriko Numao
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, 980-8578, Japan
| | - Takashi Makino
- Graduate School of Life Sciences, Tohoku University, Sendai, 980-8578, Japan
| | - Tamaki Yano
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, 980-8578, Japan
| | - Shoichiro Kurata
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, 980-8578, Japan
| |
Collapse
|
42
|
The Development and Use of Zinc-Finger Nucleases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016. [DOI: 10.1007/978-1-4939-3509-3_2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
|
43
|
Abstract
Initially identified as a marker of coiled bodies (now Cajal bodies or CBs), the protein coilin was discovered a quarter of century ago. Coilin is now known to scaffold the CB, but its structure and function are poorly understood. Nearly devoid of predicted structural motifs, coilin has numerous reported molecular interactions that must underlie its role in the formation and function of CBs. In this review, we summarize what we have learned in the past 25 years about coilin's structure, post-transcriptional modifications, and interactions with RNA and proteins. We show that genes with homology to human coilin are found in primitive metazoans and comment on differences among model organisms. Coilin's function in Cajal body formation and RNP metabolism will be discussed in the light of these developments.
Collapse
Affiliation(s)
- Martin Machyna
- a Department of Molecular Biophysics & Biochemistry ; Yale University ; New Haven , CT USA
| | | | | |
Collapse
|
44
|
dDsk2 regulates H2Bub1 and RNA polymerase II pausing at dHP1c complex target genes. Nat Commun 2015; 6:7049. [PMID: 25916810 DOI: 10.1038/ncomms8049] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2014] [Accepted: 03/26/2015] [Indexed: 12/13/2022] Open
Abstract
dDsk2 is a conserved extraproteasomal ubiquitin receptor that targets ubiquitylated proteins for degradation. Here we report that dDsk2 plays a nonproteolytic function in transcription regulation. dDsk2 interacts with the dHP1c complex, localizes at promoters of developmental genes and is required for transcription. Through the ubiquitin-binding domain, dDsk2 interacts with H2Bub1, a modification that occurs at dHP1c complex-binding sites. H2Bub1 is not required for binding of the complex; however, dDsk2 depletion strongly reduces H2Bub1. Co-depletion of the H2Bub1 deubiquitylase dUbp8/Nonstop suppresses this reduction and rescues expression of target genes. RNA polymerase II is strongly paused at promoters of dHP1c complex target genes and dDsk2 depletion disrupts pausing. Altogether, these results suggest that dDsk2 prevents dUbp8/Nonstop-dependent H2Bub1 deubiquitylation at promoters of dHP1c complex target genes and regulates RNA polymerase II pausing. These results expand the catalogue of nonproteolytic functions of ubiquitin receptors to the epigenetic regulation of chromatin modifications.
Collapse
|
45
|
Groen CM, Jayo A, Parsons M, Tootle TL. Prostaglandins regulate nuclear localization of Fascin and its function in nucleolar architecture. Mol Biol Cell 2015; 26:1901-17. [PMID: 25808493 PMCID: PMC4436834 DOI: 10.1091/mbc.e14-09-1384] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Accepted: 03/18/2015] [Indexed: 01/14/2023] Open
Abstract
Fascin, a conserved actin-bundling protein, is not only cytoplasmic but also localizes to the nucleus and nuclear periphery in both Drosophila and mammalian cell contexts. In Drosophila, prostaglandin signaling regulates this localization. In addition, Fascin plays a critical role in nucleolar architecture in both Drosophila and mammalian cells. Fascin, a highly conserved actin-bundling protein, localizes and functions at new cellular sites in both Drosophila and multiple mammalian cell types. During Drosophila follicle development, in addition to being cytoplasmic, Fascin is in the nuclei of the germline-derived nurse cells during stages 10B–12 (S10B–12) and at the nuclear periphery during stage 13 (S13). This localization is specific to Fascin, as other actin-binding proteins, Villin and Profilin, do not exhibit the same subcellular distribution. In addition, localization of fascin1 to the nucleus and nuclear periphery is observed in multiple mammalian cell types. Thus the regulation and function of Fascin at these new cellular locations is likely to be highly conserved. In Drosophila, loss of prostaglandin signaling causes a global reduction in nuclear Fascin and a failure to relocalize to the nuclear periphery. Alterations in nuclear Fascin levels result in defects in nucleolar morphology in both Drosophila follicles and cultured mammalian cells, suggesting that nuclear Fascin plays an important role in nucleolar architecture. Given the numerous roles of Fascin in development and disease, including cancer, our novel finding that Fascin has functions within the nucleus sheds new light on the potential roles of Fascin in these contexts.
Collapse
Affiliation(s)
- Christopher M Groen
- Anatomy and Cell Biology, Carver College of Medicine, University of Iowa, Iowa City, IA 52242
| | - Asier Jayo
- Randall Division of Cell and Molecular Biophysics, King's College London, London SE1 1UL, United Kingdom
| | - Maddy Parsons
- Randall Division of Cell and Molecular Biophysics, King's College London, London SE1 1UL, United Kingdom
| | - Tina L Tootle
- Anatomy and Cell Biology, Carver College of Medicine, University of Iowa, Iowa City, IA 52242
| |
Collapse
|
46
|
Gavrilov AA, Razin SV. Compartmentalization of the cell nucleus and spatial organization of the genome. Mol Biol 2015. [DOI: 10.1134/s0026893315010033] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
47
|
SART3-Dependent Accumulation of Incomplete Spliceosomal snRNPs in Cajal Bodies. Cell Rep 2015; 10:429-440. [PMID: 25600876 DOI: 10.1016/j.celrep.2014.12.030] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Revised: 09/18/2014] [Accepted: 12/13/2014] [Indexed: 12/16/2022] Open
Abstract
Cajal bodies (CBs) are evolutionarily conserved nuclear structures involved in the metabolism of spliceosomal small nuclear ribonucleoprotein particles (snRNPs). CBs are not present in all cell types, and the trigger for their formation is not yet known. Here, we depleted cells of factors required for the final steps of snRNP assembly and assayed for the presence of stalled intermediates in CBs. We show that depletion induces formation of CBs in cells that normally lack these nuclear compartments, suggesting that CB nucleation is triggered by an imbalance in snRNP assembly. Accumulation of stalled intermediates in CBs depends on the di-snRNP assembly factor SART3. SART3 is required for both the induction of CB formation as well as the tethering of incomplete snRNPs to coilin, the CB scaffolding protein. We propose a model wherein SART3 monitors tri-snRNP assembly and sequesters incomplete particles in CBs, thereby allowing cells to maintain a homeostatic balance of mature snRNPs in the nucleoplasm.
Collapse
|
48
|
Nizami ZF, Liu JL, Gall JG. Fluorescent In Situ Hybridization of Nuclear Bodies in Drosophila melanogaster Ovaries. Methods Mol Biol 2015; 1328:137-149. [PMID: 26324435 PMCID: PMC5588913 DOI: 10.1007/978-1-4939-2851-4_10] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Fluorescent in situ hybridization (FISH) is a technique for determining the cytological localization of RNA or DNA molecules. There are many approaches available for generating in situ hybridization probes and conducting the subsequent hybridization steps. Here, we describe a simple and reliable FISH method to label small RNAs (200-500 nucleotides in length) that are enriched in nuclear bodies in Drosophila melanogaster ovaries, such as Cajal bodies (CBs) and histone locus bodies (HLBs). This technique can also be applied to other Drosophila tissues, and to abundant mRNAs such as histone transcripts.
Collapse
Affiliation(s)
- Zehra F Nizami
- Department of Embryology, Carnegie Institution for Science, Baltimore, MD, 21218, USA
| | | | | |
Collapse
|
49
|
Ulianov SV, Gavrilov AA, Razin SV. Nuclear Compartments, Genome Folding, and Enhancer-Promoter Communication. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2015; 315:183-244. [DOI: 10.1016/bs.ircmb.2014.11.004] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
|
50
|
Chen Y, Deng Z, Jiang S, Hu Q, Liu H, Songyang Z, Ma W, Chen S, Zhao Y. Human cells lacking coilin and Cajal bodies are proficient in telomerase assembly, trafficking and telomere maintenance. Nucleic Acids Res 2014; 43:385-95. [PMID: 25477378 PMCID: PMC4288172 DOI: 10.1093/nar/gku1277] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The RNA component of human telomerase (hTR) localizes to Cajal bodies, and it has been proposed that Cajal bodies play a role in the assembly of telomerase holoenzyme and telomerase trafficking. Here, the role of Cajal bodies was examined in Human cells deficient of coilin (i.e. coilin-knockout (KO) cells), in which no Cajal bodies are detected. In coilin-KO cells, a normal level of telomerase activity is detected and interactions between core factors of holoenzyme are preserved, indicating that telomerase assembly occurs in the absence of Cajal bodies. Moreover, dispersed hTR aggregates and forms foci specifically during S and G2 phase in coilin-KO cells. Colocalization of these hTR foci with telomeres implies proper telomerase trafficking, independent of Cajal bodies. Therefore, telomerase adds similar numbers of TTAGGG repeats to telomeres in coilin-KO and controls cells. Overexpression of TPP1-OB-fold blocks cell cycle-dependent formation of hTR foci and inhibits telomere extension. These findings suggest that telomerase assembly, trafficking and extension occur with normal efficiency in Cajal bodies deficient human cells. Thus, Cajal bodies, as such, are not essential in these processes, although it remains possible that non-coilin components of Cajal bodies and/or telomere binding proteins (e.g. TPP1) do play roles in telomerase biogenesis and telomere homeostasis.
Collapse
Affiliation(s)
- Yanlian Chen
- Key Laboratory of Gene Engineering of the Ministry of Education, Cooperative Innovation Center for High Performance Computing, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, P.R. China
| | - Zhiqiang Deng
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education, School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, P.R. China
| | - Shuai Jiang
- Key Laboratory of Gene Engineering of the Ministry of Education, Cooperative Innovation Center for High Performance Computing, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, P.R. China
| | - Qian Hu
- Key Laboratory of Gene Engineering of the Ministry of Education, Cooperative Innovation Center for High Performance Computing, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, P.R. China
| | - Haiying Liu
- Key Laboratory of Gene Engineering of the Ministry of Education, Cooperative Innovation Center for High Performance Computing, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, P.R. China
| | - Zhou Songyang
- Key Laboratory of Gene Engineering of the Ministry of Education, Cooperative Innovation Center for High Performance Computing, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, P.R. China
| | - Wenbin Ma
- Key Laboratory of Gene Engineering of the Ministry of Education, Cooperative Innovation Center for High Performance Computing, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, P.R. China
| | - Shi Chen
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education, School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, P.R. China
| | - Yong Zhao
- Key Laboratory of Gene Engineering of the Ministry of Education, Cooperative Innovation Center for High Performance Computing, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, P.R. China
| |
Collapse
|