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Lamba R, Salam A, Anjum F, Yadav A, Garg R, Kaushik K, Sharma S, Nandi CK. NIR-emissive carbon nanodots as a tool to mark ribosomal RNA and nucleolus components using super-resolution microscopy. NANOSCALE 2024; 16:11739-11748. [PMID: 38864270 DOI: 10.1039/d4nr01569j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2024]
Abstract
Ribosomal RNA (rRNA) plays a key role in protein synthesis and ribosomal biogenesis. The exclusively used commercial dye for RNA staining is SYTO RNASelect, which works in fixed cells only. To overcome this constraint, we synthesized NIR-emissive, highly photostable, and biocompatible carbon nanodots (CNDs) as a fluorescent biomarker for rRNA. The synthesized CNDs could stain rRNA in both live and fixed cells. We were able to visualize rRNA at different sites in eukaryotic cells using super-resolution microscopy (SRM). The CNDs localized rRNA in the dense fibrillar components (DFCs) of the nucleolus, nuclear membrane, and rough endoplasmic reticulum (RER). The super-resolved hollow ring-structured DFC with an FWHM of 140 nm, nuclear membrane with an FWHM of 120 nm, and ER with an FWHM of 115 nm were observed. We further found a marked contrast between the pre-RNA synthesized in cancer cells and normal cells. We believe that these CNDs have great potential in rRNA imaging and comprehending the complex relationships between rRNA dynamics and basic biological processes, disease development, or drug interactions.
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Affiliation(s)
- Rohan Lamba
- School of Chemical Sciences, Indian Institute of Technology Mandi, H.P.-175075, India.
| | - Abdul Salam
- School of Chemical Sciences, Indian Institute of Technology Mandi, H.P.-175075, India.
| | - Farhan Anjum
- School of Biological Sciences and Bioengineering, Indian Institute of Technology Mandi, H.P.-175075, India
| | - Aditya Yadav
- School of Chemical Sciences, Indian Institute of Technology Mandi, H.P.-175075, India.
| | - Richa Garg
- School of Chemical Sciences, Indian Institute of Technology Mandi, H.P.-175075, India.
| | - Kush Kaushik
- School of Chemical Sciences, Indian Institute of Technology Mandi, H.P.-175075, India.
| | - Shagun Sharma
- School of Chemical Sciences, Indian Institute of Technology Mandi, H.P.-175075, India.
| | - Chayan Kanti Nandi
- School of Chemical Sciences, Indian Institute of Technology Mandi, H.P.-175075, India.
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2
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Liang J, Chen Y, Li S, Liu D, Tian H, Xiang Q, Zhao K, Yu X, Chen Q, Fan H, Zhang L, Penttinen P, Gu Y. Transcriptomic analysis and carbohydrate metabolism-related enzyme expression across different pH values in Rhizopus delemar. Front Microbiol 2024; 15:1359830. [PMID: 38511010 PMCID: PMC10953822 DOI: 10.3389/fmicb.2024.1359830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Accepted: 02/22/2024] [Indexed: 03/22/2024] Open
Abstract
Introduction pH is one of the important factors affecting the growth and performance of microorganisms. Methods We studied the pH response and plant growth-promoting (PGP) ability of Rhizopus delemar using cultivation experiments and transcriptomics, and verified the expression profiles using quantitative real-time PCR. Results pH affected the growth and PGP properties of R. delemar. At pH 7, the growth rate of R. delemar was rapid, whereas pH 4 and 8 inhibited mycelial growth and PGP ability, respectively. In the pot experiment, the plant height was the highest at pH 7, 56 cm, and the lowest at pH 4 and pH 5, 46.6 cm and 47 cm, respectively. Enzyme activities were highest at pH 6 to pH 7. Enzyme activities were highest at pH 6 to pH 7. Among the 1,629 differentially expressed genes (DEGs), 1,033 genes were up-regulated and 596 were down-regulated. A total of 1,623 DEGs were annotated to carbohydrate-active enzyme coding genes. Discussion The PGP characteristics, e.g., Phosphorus solubilization ability, of R. delemar were strongest at pH 7. The results provide useful information regarding the molecular mechanism of R. delemar pH response.
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Affiliation(s)
- Jinpeng Liang
- Department of Microbiology, College of Resources, Sichuan Agricultural University, Chengdu, China
| | - Yulan Chen
- Department of Microbiology, College of Resources, Sichuan Agricultural University, Chengdu, China
- Liangshan Tobacco Corporation of Sichuan Province, Xichang, China
| | - Sisi Li
- Department of Microbiology, College of Resources, Sichuan Agricultural University, Chengdu, China
| | - Dongyang Liu
- Department of Microbiology, College of Resources, Sichuan Agricultural University, Chengdu, China
- Liangshan Tobacco Corporation of Sichuan Province, Xichang, China
| | - Hong Tian
- Department of Microbiology, College of Resources, Sichuan Agricultural University, Chengdu, China
| | - Quanju Xiang
- Department of Microbiology, College of Resources, Sichuan Agricultural University, Chengdu, China
| | - Ke Zhao
- Department of Microbiology, College of Resources, Sichuan Agricultural University, Chengdu, China
| | - Xiumei Yu
- Department of Microbiology, College of Resources, Sichuan Agricultural University, Chengdu, China
| | - Qiang Chen
- Department of Microbiology, College of Resources, Sichuan Agricultural University, Chengdu, China
| | - Hongzhu Fan
- Institute of Agricultural Resources and Environmental Science, Sichuan Academy of Agricultural Sciences, Chengdu, China
| | - Lingzi Zhang
- Department of Microbiology, College of Resources, Sichuan Agricultural University, Chengdu, China
| | - Petri Penttinen
- Department of Microbiology, College of Resources, Sichuan Agricultural University, Chengdu, China
| | - Yunfu Gu
- Department of Microbiology, College of Resources, Sichuan Agricultural University, Chengdu, China
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Sun L, Sun B, Chen L, Ge Q, Chen K. Identification of genes associated with the silk gland size using multi-omics in silkworm (Bombyx mori). INSECT MOLECULAR BIOLOGY 2024; 33:1-16. [PMID: 37676698 DOI: 10.1111/imb.12870] [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: 03/29/2023] [Accepted: 08/17/2023] [Indexed: 09/08/2023]
Abstract
Silk gland size in silkworms (Bombyx mori) affects silk output. However, the molecular mechanisms by which genes regulate silk gland size remain unclear. In this study, silk glands from three pure silkworm strains (A798, A306 and XH) with different silk gland weight phenotypes were compared using transcriptomics and proteomics to identify differentially expressed genes (DEGs) and proteins (DEPs). When comparing A798 to A306 and A798 to XH, 830 and 469 DEGs were up-regulated, respectively. These genes were related to the gene ontology terms, metabolic process, transport activity and biosynthesis process. In addition, 372 and 302 up-regulated differentially expressed proteins were detected in A798 to A306 and A798 to XH, respectively, related to the gene ontology terms, ribosome and protein export, ribosome and polypeptide biosynthesis processes. Moreover, combined transcriptomics, proteomics and weighted correlation network analyses showed that five genes (BGIBMGA002524, BGIBMGA002629, BGIBMGA005659, BGIBMGA005711 and BGIBMGA010889) were significantly associated with the silk gland weight. Reverse Transcription-quantitative real-time Polymerase Chain Reaction (RT-qPCR) and Enzyme linked immunosorbent assay (ELISA) were used to verify the mRNA and protein expression of five genes in the silk glands and tissues of 18 silkworm strains. The results showed that four genes have higher expression levels in heavier silk glands. These genes are associated with glycogen metabolism, fatty acid synthesis and branched chain amino acid metabolism, thus potentially promoting growth and silk protein synthesis. These findings provide valuable insights into the molecular mechanisms underlying the relationship between silk gland weight and silk yield in silkworms.
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Affiliation(s)
- Lindan Sun
- School of Life Sciences, Jiangsu University, Zhenjiang, China
| | - Binbin Sun
- School of Life Sciences, Jiangsu University, Zhenjiang, China
| | - Liang Chen
- School of Life Sciences, Jiangsu University, Zhenjiang, China
| | - Qi Ge
- School of Life Sciences, Jiangsu University, Zhenjiang, China
| | - Keping Chen
- School of Life Sciences, Jiangsu University, Zhenjiang, China
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4
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Zhang Y, Lei Y, Dong Y, Chen S, Sun S, Zhou F, Zhao Z, Chen B, Wei L, Chen J, Meng Z. Emerging roles of RNA ac4C modification and NAT10 in mammalian development and human diseases. Pharmacol Ther 2024; 253:108576. [PMID: 38065232 DOI: 10.1016/j.pharmthera.2023.108576] [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: 08/19/2023] [Revised: 11/29/2023] [Accepted: 12/01/2023] [Indexed: 01/13/2024]
Abstract
RNA ac4C modification is a novel and rare chemical modification observed in mRNA. Traditional biochemical studies had primarily associated ac4C modification with tRNA and rRNA until in 2018, Arango D et al. first reported the presence of ac4C modification on mRNA and demonstrated its critical role in mRNA stability and translation regulation. Furthermore, they established that the ac4C modification on mRNA is mediated by the classical N-acetyltransferase NAT10. Subsequent studies have underscored the essential implications of NAT10 and mRNA ac4C modification across both physiological and pathological regulatory processes. In this review, we aimed to explore the discovery history of RNA ac4C modification, its detection methods, and its regulatory mechanisms in disease and physiological development. We offer a forward-looking examination and discourse concerning the employment of RNA ac4C modification as a prospective therapeutic strategy across diverse diseases. Furthermore, we comprehensively summarize the functions and mechanisms of NAT10 in gene expression regulation and pathogenesis independent of RNA ac4C modification.
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Affiliation(s)
- Yigan Zhang
- Institute of Biomedical Research, Department of Infectious Diseases, Regulatory Mechanism and Targeted Therapy for Liver Cancer Shiyan Key Laboratory, Hubei rovincial Clinical Research Center for Precise Diagnosis and Treatment of Liver Cancer, Taihe Hospital, Hubei University of Medicine, Shiyan, Hubei, 442000, China; Hubei Key Laboratory of Embryonic Stem Cell Research, Taihe Hospital, Hubei University of Medicine, Shiyan, Hubei, 442000, China
| | - Yumei Lei
- Key Laboratory of Precision Nutrition and Food Quality, Department of Nutrition and Health, China Agricultural University, Beijing, China
| | - Yanbin Dong
- Institute of Biophysics, Chinese Academy of Sciences, Key Laboratory of Nucleic Acid Biology, Chinese Academy of Sciences, Beijing, China
| | - Shuwen Chen
- School of Biomedical Engineering, Hubei University of Medicine, Shiyan, China
| | - Siyuan Sun
- Key Laboratory of Precision Nutrition and Food Quality, Department of Nutrition and Health, China Agricultural University, Beijing, China
| | - Fange Zhou
- The First Clinical School of Hubei University of Medicine, Shiyan, China
| | - Zhiwen Zhao
- Department of Emergency Medicine, Taihe Hospital, Hubei University of Medicine, Shiyan, China
| | - Bonan Chen
- Department of Anatomical and Cellular Pathology, State Key Laboratory of Translational Oncology, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, China
| | - Lv Wei
- Institute of Biophysics, Chinese Academy of Sciences, Key Laboratory of Nucleic Acid Biology, Chinese Academy of Sciences, Beijing, China.
| | - Juan Chen
- Key Laboratory of Precision Nutrition and Food Quality, Department of Nutrition and Health, China Agricultural University, Beijing, China.
| | - Zhongji Meng
- Institute of Biomedical Research, Department of Infectious Diseases, Regulatory Mechanism and Targeted Therapy for Liver Cancer Shiyan Key Laboratory, Hubei rovincial Clinical Research Center for Precise Diagnosis and Treatment of Liver Cancer, Taihe Hospital, Hubei University of Medicine, Shiyan, Hubei, 442000, China; Hubei Key Laboratory of Embryonic Stem Cell Research, Taihe Hospital, Hubei University of Medicine, Shiyan, Hubei, 442000, China.
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5
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Romero S, Unchwaniwala N, Evans EL, Eliceiri KW, Loeb DD, Sherer NM. Live Cell Imaging Reveals HBV Capsid Translocation from the Nucleus To the Cytoplasm Enabled by Cell Division. mBio 2023; 14:e0330322. [PMID: 36809075 PMCID: PMC10127671 DOI: 10.1128/mbio.03303-22] [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: 11/29/2022] [Accepted: 01/17/2023] [Indexed: 02/23/2023] Open
Abstract
Hepatitis B virus (HBV) capsid assembly is traditionally thought to occur predominantly in the cytoplasm, where the virus gains access to the virion egress pathway. To better define sites of HBV capsid assembly, we carried out single cell imaging of HBV Core protein (Cp) subcellular trafficking over time under conditions supporting genome packaging and reverse transcription in Huh7 hepatocellular carcinoma cells. Time-course analyses including live cell imaging of fluorescently tagged Cp derivatives showed Cp to accumulate in the nucleus at early time points (~24 h), followed by a marked re-distribution to the cytoplasm at 48 to 72 h. Nucleus-associated Cp was confirmed to be capsid and/or high-order assemblages using a novel dual label immunofluorescence strategy. Nuclear-to-cytoplasmic re-localization of Cp occurred predominantly during nuclear envelope breakdown in conjunction with cell division, followed by strong cytoplasmic retention of Cp. Blocking cell division resulted in strong nuclear entrapment of high-order assemblages. A Cp mutant, Cp-V124W, predicted to exhibit enhanced assembly kinetics, also first trafficked to the nucleus to accumulate at nucleoli, consistent with the hypothesis that Cp's transit to the nucleus is a strong and constitutive process. Taken together, these results provide support for the nucleus as an early-stage site of HBV capsid assembly, and provide the first dynamic evidence of cytoplasmic retention after cell division as a mechanism underpinning capsid nucleus-to-cytoplasm relocalization. IMPORTANCE Hepatitis B virus (HBV) is an enveloped, reverse-transcribing DNA virus that is a major cause of liver disease and hepatocellular carcinoma. Subcellular trafficking events underpinning HBV capsid assembly and virion egress remain poorly characterized. Here, we developed a combination of fixed and long-term (>24 h) live cell imaging technologies to study the single cell trafficking dynamics of the HBV Core Protein (Cp). We demonstrate that Cp first accumulates in the nucleus, and forms high-order structures consistent with capsids, with the predominant route of nuclear egress being relocalization to the cytoplasm during cell division in conjunction with nuclear membrane breakdown. Single cell video microscopy demonstrated unequivocally that Cp's localization to the nucleus is constitutive. This study represents a pioneering application of live cell imaging to study HBV subcellular transport, and demonstrates links between HBV Cp and the cell cycle.
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Affiliation(s)
- Sofia Romero
- McArdle Laboratory for Cancer Research (Department of Oncology), University of Wisconsin-Madison School of Medicine and Public Health, Madison, Wisconsin, USA
- Institute for Molecular Virology, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Carbone Cancer Center, University of Wisconsin-Madison School of Medicine and Public Health, Madison, Wisconsin, USA
| | - Nuruddin Unchwaniwala
- McArdle Laboratory for Cancer Research (Department of Oncology), University of Wisconsin-Madison School of Medicine and Public Health, Madison, Wisconsin, USA
- Institute for Molecular Virology, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Carbone Cancer Center, University of Wisconsin-Madison School of Medicine and Public Health, Madison, Wisconsin, USA
| | - Edward L. Evans
- Laboratory for Optical and Computational Instrumentation, Center for Quantitative Cell Imaging, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Morgridge Institute for Research, Madison, Wisconsin, USA
| | - Kevin W. Eliceiri
- Laboratory for Optical and Computational Instrumentation, Center for Quantitative Cell Imaging, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Morgridge Institute for Research, Madison, Wisconsin, USA
| | - Daniel D. Loeb
- McArdle Laboratory for Cancer Research (Department of Oncology), University of Wisconsin-Madison School of Medicine and Public Health, Madison, Wisconsin, USA
- Carbone Cancer Center, University of Wisconsin-Madison School of Medicine and Public Health, Madison, Wisconsin, USA
| | - Nathan M. Sherer
- McArdle Laboratory for Cancer Research (Department of Oncology), University of Wisconsin-Madison School of Medicine and Public Health, Madison, Wisconsin, USA
- Institute for Molecular Virology, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Carbone Cancer Center, University of Wisconsin-Madison School of Medicine and Public Health, Madison, Wisconsin, USA
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6
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Genomic and Transcriptomic Insights into Salinity Tolerance-Based Niche Differentiation of Synechococcus Clades in Estuarine and Coastal Waters. mSystems 2023; 8:e0110622. [PMID: 36622156 PMCID: PMC9948718 DOI: 10.1128/msystems.01106-22] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Cluster 5 Synechococcus is one of the most important primary producers on earth. However, ecotypes of this genus exhibit complex geographical distributions, and the genetic basis of niche partitioning is still not fully understood. Here, we report distinct distributions of subcluster 5.1 (SC5.1) and subcluster 5.2 (SC5.2) Synechococcus in estuarine waters, and we reveal that salinity is the main factor determining their distribution. Clade III (belonging to SC5.1) and CB4 (belonging to SC5.2) are dominant clades in the study region, with different ecological distributions. We further conducted physiological, genomic, and transcriptomic studies of Synechococcus strains YX04-3 and HK05, which are affiliated with clade III and CB4, respectively. Laboratory tests showed that HK05 could grow at low salinity (13 ppt), whereas the growth of YX04-3 was suppressed when salinity decreased to 13 ppt. Genomic and transcriptomic analysis suggested that euryhaline clade CB4 is capable of dealing with a sudden drop of salinity by releasing compatible solutes through mechanosensitive channels that are coded by the mscL gene, decreasing biosynthesis of organic osmolytes, and increasing expression of heat shock proteins and high light-inducible proteins to protect photosystem. Furthermore, CB4 strain HK05 exhibited a higher growth rate when growing at low salinity than at high salinity. This is likely achieved by reducing its biosynthesis of organic osmolyte activity and increasing its photosynthetic activity at low salinity, which allowed it to enhance the assimilation of inorganic carbon and nitrogen. Together, these results provide new insights regarding the ecological distribution of SC5.2 and SC5.1 ecotypes and their underlying molecular mechanisms. IMPORTANCE Synechococcus is a group of unicellular Cyanobacteria that are widely distributed in global aquatic ecosystems. Salinity is a factor that affects the distribution of microorganisms in estuarine and coastal environments. In this study, we studied the distribution pattern of Synechococcus community along the salinity gradient in a subtropical estuary. By using omic methods, we unveiled genetic traits that determine the niche partitioning of euryhaline and strictly marine Synechococcus. We also explored the strategies employed by euryhaline Synechococcus to cope with a sudden drop of salinity, and revealed possible mechanisms for the higher growth rate of euryhaline Synechococcus in low salinity conditions. This study provides new insight into the genetic basis of niche partitioning of Synechococcus clades.
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Martínez-Férriz A, Ferrando A, Fathinajafabadi A, Farràs R. Ubiquitin-mediated mechanisms of translational control. Semin Cell Dev Biol 2022; 132:146-154. [PMID: 34952788 DOI: 10.1016/j.semcdb.2021.12.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 12/16/2021] [Accepted: 12/17/2021] [Indexed: 12/15/2022]
Abstract
mRNAs translation to proteins constitutes an important step of cellular gene expression that is highly regulated in response to different extracellular stimuli and stress situations. The fine control of protein synthesis is carried out both qualitatively and quantitatively, depending on the cellular demand at each moment. Post-translational modifications, in turn regulated by intracellular signaling pathways, play a key role in translation regulation. Among them, ubiquitination, whose role is becoming increasingly important in the control of translation, determines a correct balance between protein synthesis and degradation. In this review we focus on the role of ubiquitination (both degradative K48-linkage type and non-degradative K63-linkage type and monoubiquitination) in eukaryotic translation, both at the pre-translational level during the biogenesis/degradation of the components of translational machinery as well as at the co-translational level under stressful conditions. We also discuss other ubiquitin-dependent regulatory mechanisms of mRNA protection and resumption of translation after stress removal, where the ubiquitination of ribosomal proteins and associated regulatory proteins play an important role in the global rhythm of translation.
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Affiliation(s)
- Arantxa Martínez-Férriz
- Oncogenic Signalling Laboratory, Centro de Investigación Príncipe Felipe (CIPF), Valencia, Spain
| | - Alejandro Ferrando
- Instituto de Biología Molecular y Celular de Plantas CSIC-Universidad Politécnica de Valencia, Valencia, Spain
| | - Alihamze Fathinajafabadi
- Oncogenic Signalling Laboratory, Centro de Investigación Príncipe Felipe (CIPF), Valencia, Spain.
| | - Rosa Farràs
- Oncogenic Signalling Laboratory, Centro de Investigación Príncipe Felipe (CIPF), Valencia, Spain.
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8
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Wu D, Hou Y, Cheng J, Han T, Hao N, Zhang B, Fan X, Ji X, Chen F, Gong D, Wang L, McGinn P, Zhao L, Chen S. Transcriptome analysis of lipid metabolism in response to cerium stress in the oleaginous microalga Nannochloropsis oculata. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 838:156420. [PMID: 35660445 DOI: 10.1016/j.scitotenv.2022.156420] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 05/28/2022] [Accepted: 05/30/2022] [Indexed: 06/15/2023]
Abstract
Nannochloropsis oculata can accumulate large amounts of lipids under rare earth element (REE) conditions. However, the lipid accumulation mechanism responsible for REE stress has not been elucidated. In this study, the effects of cerium (the most abundant REE) on the growth and lipid accumulation of N. oculata were investigated. The de novo transcriptome data of N. oculata under cerium conditions were subsequently collected and analyzed. The results showed that N. oculata exhibited good cerium-resistance ability, showed slightly decrease in biomass but significantly increase in lipid content (55.8 % dry cell weight) under 6.0 mg/L cerium condition. Meanwhile, about 83.4 % cerium was biological fixated. Through transcriptome analysis, we found that the inhibited photosynthesis and carbon fixation pathways coupled with the stress-sensitive expression of ribosome biogenesis genes acclimatized the cells to REE stress. The active glycolysis pathway accelerated carbon flux to pyruvate and acetyl-CoA, and the upregulation of glycerol kinase and phosphatidate cytidylyltransferase genes further induced lipid accumulation. In addition, cerium downregulated the acyl-CoA oxidase and triacylglycerol lipase genes, which inhibited the degradation of lipids. Therefore, different responses to cerium demonstrate how N. oculata cells adapt to REE stress, and this knowledge may be used to extend our understanding of triacylglycerol (TAG) and the synthesis of other important metabolites.
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Affiliation(s)
- Di Wu
- School of Life Science and Technology, Inner Mongolia University of Science and Technology, Baotou 014010, China
| | - Yuyong Hou
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China; National Center of Technology Innovation for Synthetic Biology, Tianjin, China
| | - Jie Cheng
- School of Life Science and Technology, Inner Mongolia University of Science and Technology, Baotou 014010, China
| | - Tong Han
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
| | - Nahui Hao
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
| | - Bingjie Zhang
- Department of Food Engineering, Anhui Science and Technology Trade School, Bengbu 233080, China
| | - Xiang Fan
- Department of Food Engineering, Anhui Science and Technology Trade School, Bengbu 233080, China
| | - Xiang Ji
- School of Life Science and Technology, Inner Mongolia University of Science and Technology, Baotou 014010, China.
| | - Fangjian Chen
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China; National Center of Technology Innovation for Synthetic Biology, Tianjin, China.
| | - Donghui Gong
- School of Life Science and Technology, Inner Mongolia University of Science and Technology, Baotou 014010, China
| | - Lei Wang
- School of Life Science and Technology, Inner Mongolia University of Science and Technology, Baotou 014010, China
| | - Patrick McGinn
- National Research Council Canada, 1200 Montreal Road, Building M-58, Ottawa, Ontario K1A 0R6, Canada
| | - Lei Zhao
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China; National Center of Technology Innovation for Synthetic Biology, Tianjin, China.
| | - Shulin Chen
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
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Li YR, Zong RQ, Zhang HY, Meng XY, Wu FX. Mechanism Analysis of LINC00665 and Its Peptides CIP2A-BP in Hepatocellular Carcinoma. Front Genet 2022; 13:861096. [PMID: 35350239 PMCID: PMC8957827 DOI: 10.3389/fgene.2022.861096] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 02/14/2022] [Indexed: 11/13/2022] Open
Abstract
Background: More and more studies show that long non-coding RNAs (lncRNAs) have miniature open reading frames that can be translated into short peptides. Here, we identify the long non-coding gene LINC00665 and its short peptides (CIP2A-BP) in hepatocellular carcinoma (HCC) and explore how they contribute to HCC progression. Materials and methods: First, GSE101728 data were acquired through the Gene Expression Omnibus for identification of differentially expressed genes (DEGs), and gene set enrichment analysis (GSEA) was conducted to find enriched biological pathways. Then, further bioinformatics analysis was carried out on the screened long non-coding genes, and LINC00665 expression was detected in HCC and normal liver samples. The relations between LINC00665 expression, HCC prognosis, and clinical characteristics were studied. Receiver operating characteristic (ROC) analysis was also applied to verify the LINC00665 prediction in HCC prognosis. In addition, pertinent experiments on LINC00665 and CIP2A-BP were also carried out to explore their roles in the progression of HCC. Results: As a result, we screened out 332 DEGs in total, including 130 upregulated and 202 downregulated DEGs. These DEGs were mainly enriched in posttranscriptional regulation of gene expression, RNA processing, nucleolus, and gene silencing biological pathways. In addition, we found that LINC00665 was increased in HCC samples, which substantially indicated its poor prognosis. Compared with normal tissues, LINC00665 had higher expression in the pathological stages III and IV, tumor-free groups, people no more than 60 years old, and stages T3, T4, N0, N1, and M1. ROC curve indicated that the variable INC00665 had certain accuracy in predicting overall survival (OS). Moreover, in functional experiments, LINC00665 knockdown could significantly decrease HCC cell proliferation, migration, and invasion, while overexpressed CIP2A-BP could markedly increase HCC cell proliferation, invasion, and migration. Conclusion: Our findings not only disclose a unique mechanism by which CIP2A-BP encoded by LINC00665 promotes HCC carcinogenesis but suggest that these long non-coding genes and short peptides could be used as biomarkers for HCC diagnosis and prognosis and new targets for HCC therapy.
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Affiliation(s)
- Yi-Ran Li
- Department of Intensive Care Medicine, Eastern Hepatobiliary Surgery Hospital, The Third Affiliated Hospital of Naval Medical University, Shanghai, China
| | - Rui-Qing Zong
- Department of Intensive Care Medicine, Eastern Hepatobiliary Surgery Hospital, The Third Affiliated Hospital of Naval Medical University, Shanghai, China
| | - Hong-Yan Zhang
- Department of Intensive Care Medicine, Eastern Hepatobiliary Surgery Hospital, The Third Affiliated Hospital of Naval Medical University, Shanghai, China
| | - Xiao-Yan Meng
- Department of Intensive Care Medicine, Eastern Hepatobiliary Surgery Hospital, The Third Affiliated Hospital of Naval Medical University, Shanghai, China
| | - Fei-Xiang Wu
- Department of Intensive Care Medicine, Eastern Hepatobiliary Surgery Hospital, The Third Affiliated Hospital of Naval Medical University, Shanghai, China
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10
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Sadova AA, Panteleev DY, Pavlova GV. Zooming in: PAGE-Northern Blot Helps to Analyze Anti-Sense Transcripts Originating from Human rIGS under Transcriptional Stress. Noncoding RNA 2021; 7:ncrna7030050. [PMID: 34449671 PMCID: PMC8395900 DOI: 10.3390/ncrna7030050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 08/10/2021] [Accepted: 08/20/2021] [Indexed: 11/16/2022] Open
Abstract
Ribosomal intergenic spacer (rIGS), located between the 45S rRNA coding arrays in humans, is a deep, unexplored source of small and long non-coding RNA molecules transcribed in certain conditions to help a cell generate a stress response, pass through a differentiation state or fine tune the functioning of the nucleolus as a ribosome biogenesis center of the cell. Many of the non-coding transcripts originating from the rIGS are not characterized to date. Here, we confirm the transcriptional activity of the region laying a 2 kb upstream of the rRNA promoter, and demonstrate its altered expression under transcriptional stress, induced by a wide range of known transcription inhibitors. We managed to show an increased variability of anti-sense transcripts in alpha-amanitin treated cells by applying the low-molecular RNA fraction extracted from agarose gel to PAGE-northern. Also, the fractioning of RNA by size using agarose gel slices occurred, being applicable for determining the sizes of target transcripts via RT-PCR.
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Affiliation(s)
- Anastasia A. Sadova
- Academic Chair of Biochemistry and Molecular Biology, Faculty of General Medicine, Pirogov Russian National Research Medical University, 117997 Moscow, Russia
- Institute of Biomedical Problems, Russian Academy of Sciences, 123007 Moscow, Russia
- Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, 117485 Moscow, Russia; (D.Y.P.); (G.V.P.)
- Correspondence:
| | - Dmitry Y. Panteleev
- Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, 117485 Moscow, Russia; (D.Y.P.); (G.V.P.)
| | - Galina V. Pavlova
- Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, 117485 Moscow, Russia; (D.Y.P.); (G.V.P.)
- Institute of Molecular Medicine, Sechenov First Moscow State Medical University, 119991 Moscow, Russia
- Department of X-ray and Radioisotope Diagnostic Methods, Burdenko Neurosurgical Institute, 125047 Moscow, Russia
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11
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Figueiredo VC, Wen Y, Alkner B, Fernandez-Gonzalo R, Norrbom J, Vechetti IJ, Valentino T, Mobley CB, Zentner GE, Peterson CA, McCarthy JJ, Murach KA, von Walden F. Genetic and epigenetic regulation of skeletal muscle ribosome biogenesis with exercise. J Physiol 2021; 599:3363-3384. [PMID: 33913170 DOI: 10.1113/jp281244] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 04/20/2021] [Indexed: 12/16/2022] Open
Abstract
KEY POINTS Ribosome biogenesis and MYC transcription are associated with acute resistance exercise (RE) and are distinct from endurance exercise in human skeletal muscle throughout a 24 h time course of recovery. A PCR-based method for relative ribosomal DNA (rDNA) copy number estimation was validated by whole genome sequencing and revealed that rDNA dosage is positively correlated with ribosome biogenesis in response to RE. Acute RE modifies rDNA methylation patterns in enhancer, intergenic spacer and non-canonical MYC-associated regions, but not the promoter. Myonuclear-specific rDNA methylation patterns with acute mechanical overload in mice corroborate and expand on rDNA findings with RE in humans. A genetic predisposition for hypertrophic responsiveness may exist based on rDNA gene dosage. ABSTRACT Ribosomes are the macromolecular engines of protein synthesis. Skeletal muscle ribosome biogenesis is stimulated by exercise, although the contribution of ribosomal DNA (rDNA) copy number and methylation to exercise-induced rDNA transcription is unclear. To investigate the genetic and epigenetic regulation of ribosome biogenesis with exercise, a time course of skeletal muscle biopsies was obtained from 30 participants (18 men and 12 women; 31 ± 8 years, 25 ± 4 kg m-2 ) at rest and 30 min, 3 h, 8 h and 24 h after acute endurance (n = 10, 45 min cycling, 70% V ̇ O 2 max ) or resistance exercise (n = 10, 4 × 7 × 2 exercises); 10 control participants underwent biopsies without exercise. rDNA transcription and dosage were assessed using quantitative PCR and whole genome sequencing. rDNA promoter methylation was investigated using massARRAY EpiTYPER and global rDNA CpG methylation was assessed using reduced-representation bisulphite sequencing. Ribosome biogenesis and MYC transcription were associated primarily with resistance but not endurance exercise, indicating preferential up-regulation during hypertrophic processes. With resistance exercise, ribosome biogenesis was associated with rDNA gene dosage, as well as epigenetic changes in enhancer and non-canonical MYC-associated areas in rDNA, but not the promoter. A mouse model of in vivo metabolic RNA labelling and genetic myonuclear fluorescence labelling validated the effects of an acute hypertrophic stimulus on ribosome biogenesis and Myc transcription, and also corroborated rDNA enhancer and Myc-associated methylation alterations specifically in myonuclei. The present study provides the first information on skeletal muscle genetic and rDNA gene-wide epigenetic regulation of ribosome biogenesis in response to exercise, revealing novel roles for rDNA dosage and CpG methylation.
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Affiliation(s)
- Vandré C Figueiredo
- Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, KY, USA.,The Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
| | - Yuan Wen
- The Center for Muscle Biology, University of Kentucky, Lexington, KY, USA.,Department of Physiology, University of Kentucky, Lexington, KY, USA
| | - Björn Alkner
- Department of Orthopaedics, Eksjö, Region Jönköping County and Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Rodrigo Fernandez-Gonzalo
- Division of Clinical Physiology, Department of Laboratory Medicine, Karolinska Institutet, and Unit of Clinical Physiology, Karolinska University Hospital, Stockholm, Sweden
| | - Jessica Norrbom
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Ivan J Vechetti
- The Center for Muscle Biology, University of Kentucky, Lexington, KY, USA.,Department of Nutrition and Health Sciences, University of Nebraska, Lincoln, NE, USA
| | - Taylor Valentino
- The Center for Muscle Biology, University of Kentucky, Lexington, KY, USA.,Department of Physiology, University of Kentucky, Lexington, KY, USA
| | - C Brooks Mobley
- The Center for Muscle Biology, University of Kentucky, Lexington, KY, USA.,Department of Physiology, University of Kentucky, Lexington, KY, USA
| | | | - Charlotte A Peterson
- Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, KY, USA.,The Center for Muscle Biology, University of Kentucky, Lexington, KY, USA.,Department of Physiology, University of Kentucky, Lexington, KY, USA
| | - John J McCarthy
- The Center for Muscle Biology, University of Kentucky, Lexington, KY, USA.,Department of Physiology, University of Kentucky, Lexington, KY, USA
| | - Kevin A Murach
- Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, KY, USA.,The Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
| | - Ferdinand von Walden
- The Center for Muscle Biology, University of Kentucky, Lexington, KY, USA.,Department of Physiology, University of Kentucky, Lexington, KY, USA.,Division of Pediatric Neurology, Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden
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12
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Harrison RES, Weng K, Wang Y, Peng Q. Phase Separation and Histone Epigenetics in Genome Regulation. CURRENT OPINION IN SOLID STATE & MATERIALS SCIENCE 2021; 25:100892. [PMID: 33519290 PMCID: PMC7845916 DOI: 10.1016/j.cossms.2020.100892] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Liquid-liquid phase separation is increasingly recognized as a phenomenon that affects cell behavior. For example, phase separation of transcription factors and coactivators has been shown to drive efficient transcription. For many years, phase separation of intracellular components has been observed; however, only recently have researchers been able to garner functional significance from such events. Inspired from recent literature that describes phase separation of chromatin in a histone-dependent manner, we review the role and effect of phase separation and histone epigenetics in regulating the genome and discuss how these phenomena can be leveraged to control cell behavior.
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Affiliation(s)
- Reed E. S. Harrison
- Department of Bioengineering, University of California, San Diego, La Jolla, CA 92093, USA
- Institute of Engineering in Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Kegui Weng
- Department of Bioengineering, University of California, San Diego, La Jolla, CA 92093, USA
- Institute of Engineering in Medicine, University of California, San Diego, La Jolla, CA 92093, USA
- Chongqing University Cancer Hospital & Chongqing Cancer Institute & Chongqing Cancer Hospital, Chongqing, 400044, P. R. China
| | - Yingxiao Wang
- Department of Bioengineering, University of California, San Diego, La Jolla, CA 92093, USA
- Institute of Engineering in Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Qin Peng
- Department of Bioengineering, University of California, San Diego, La Jolla, CA 92093, USA
- Institute of Engineering in Medicine, University of California, San Diego, La Jolla, CA 92093, USA
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13
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Cell trapping microfluidic chip made of Cyclo olefin polymer enabling two concurrent cell biology experiments with long term durability. Biomed Microdevices 2020; 22:20. [DOI: 10.1007/s10544-020-0474-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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14
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Tokunaga M, Miyamoto Y, Suzuki T, Otani M, Inuki S, Esaki T, Nagao C, Mizuguchi K, Ohno H, Yoneda Y, Okamoto T, Oka M, Matsuura Y. Novel anti-flavivirus drugs targeting the nucleolar distribution of core protein. Virology 2019; 541:41-51. [PMID: 31826845 DOI: 10.1016/j.virol.2019.11.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2019] [Revised: 11/27/2019] [Accepted: 11/27/2019] [Indexed: 01/04/2023]
Abstract
The risk of infectious diseases caused by Flavivirus is increasing globally. Here, we developed a novel high-throughput screening (HTS) system to evaluate the inhibitory effects of compounds targeting the nuclear localization of the flavivirus core protein. We screened 4000 compounds based on their ability to inhibit the nuclear localization of the core protein, and identified over 20 compounds including inhibitors for cyclin dependent kinase and glycogen synthase kinase. The efficacy of the identified compounds to suppress viral growth was validated in a cell-based infection system. Remarkably, the nucleolus morphology was affected by the treatment with the compounds, suggesting that the nucleolus function is critical for viral propagation. The present HTS system provides a useful strategy for the identification of antivirals against flavivirus by targeting the nucleolar localization of the core protein.
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Affiliation(s)
- Makoto Tokunaga
- Institute for Advanced Co-Creation Studies, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Yoichi Miyamoto
- Laboratory of Nuclear Transport Dynamics, National Institutes of Biomedical Innovation, Health and Nutrition (NIBIOHN), Osaka, Japan
| | - Tatsuya Suzuki
- Institute for Advanced Co-Creation Studies, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Mayumi Otani
- Laboratory of Nuclear Transport Dynamics, National Institutes of Biomedical Innovation, Health and Nutrition (NIBIOHN), Osaka, Japan
| | - Shinsuke Inuki
- Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto, Japan
| | - Tsuyoshi Esaki
- Laboratory of Bioinformatics, Artificial Intelligence Center for Health and Biomedical Research, National Institute of Biomedical Innovation, National Institutes of Biomedical Innovation, Health and Nutrition (NIBIOHN), Osaka, Japan; Center for Data Science Education and Research, Shiga University, Shiga, Japan
| | - Chioko Nagao
- Laboratory of In-silico Drug Design, Center for Drug Design Research, National Institute of Biomedical Innovation, National Institutes of Biomedical Innovation, Health and Nutrition (NIBIOHN), Osaka, Japan
| | - Kenji Mizuguchi
- Laboratory of Bioinformatics, Artificial Intelligence Center for Health and Biomedical Research, National Institute of Biomedical Innovation, National Institutes of Biomedical Innovation, Health and Nutrition (NIBIOHN), Osaka, Japan; Laboratory of In-silico Drug Design, Center for Drug Design Research, National Institute of Biomedical Innovation, National Institutes of Biomedical Innovation, Health and Nutrition (NIBIOHN), Osaka, Japan; Institute for Protein Research, Osaka University, Osaka, Japan
| | - Hiroaki Ohno
- Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto, Japan
| | - Yoshihiro Yoneda
- National Institutes of Biomedical Innovation, Health and Nutrition (NIBIOHN), Osaka, Japan
| | - Toru Okamoto
- Institute for Advanced Co-Creation Studies, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan.
| | - Masahiro Oka
- Laboratory of Nuclear Transport Dynamics, National Institutes of Biomedical Innovation, Health and Nutrition (NIBIOHN), Osaka, Japan.
| | - Yoshiharu Matsuura
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
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15
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Puf6 and Loc1 Are the Dedicated Chaperones of Ribosomal Protein Rpl43 in Saccharomyces cerevisiae. Int J Mol Sci 2019; 20:ijms20235941. [PMID: 31779129 PMCID: PMC6928942 DOI: 10.3390/ijms20235941] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 11/25/2019] [Accepted: 11/25/2019] [Indexed: 12/11/2022] Open
Abstract
Ribosomal proteins are highly expressed, and the quality of ribosomal proteins must be rigorously controlled to build up a functional ribosome. Rpl43, ribosomal protein large subunit 43, is located nearby the E-site of ribosomes. In our previous study, we found that Puf6, Loc1, and Rpl43 form a trimeric complex in Saccharomyces cerevisiae. Rpl43 protein levels are under-accumulated in the absence of PUF6 or LOC1. However, why the loss of Puf6 or Loc1 decreased the protein levels of Rpl43 remained unclear. In the present study, we further dissected the connections among these three proteins and found that the processing defects of pre-ribosomal RNA in puf6Δ and loc1Δ are similar to those of the mutant with depletion of Rpl43. The stability of newly synthesized Rpl43 protein decreased slightly in puf6Δ and significantly in loc1Δ. We also found that Puf6 and Loc1 could interact with nascent Rpl43 co-translationally via the N-terminus of Rpl43. While the association and dissociation of Rpl43 with karyopherins did not depend on Puf6 and Loc1, Puf6 and Loc1 interacted with nascent Rpl43 in collaboration. While the N-terminus of Puf6 contained nuclear localization signals for transport, the PUF (Pumilio) domain was essential to interaction with Loc1, Rpl43, and 60S subunits. The C-terminus of Loc1 is more important for interaction with Puf6 and Rpl43. In this study, we found that Puf6 and Loc1 are the dedicated chaperones of ribosomal protein Rpl43 and also analyzed the potential interaction domains among the three proteins. Correct formation of the Puf6, Loc1, and Rpl43 ternary complex is required to properly proceed to the next step in 60S biogenesis.
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16
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Cheng Q, Zhou Q, Jin Z, Jiang Y, Xu L, Jiang H, Zhao Y. Bioaccumulation, growth performance, and transcriptomic response of Dictyosphaerium sp. after exposure to nonylphenol. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 687:416-422. [PMID: 31212149 DOI: 10.1016/j.scitotenv.2019.06.136] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 06/07/2019] [Accepted: 06/08/2019] [Indexed: 06/09/2023]
Abstract
Algal cultures of Dictyosphaerium sp. were treated with a wide range (0-8 mg/L) of nonylphenol (NP) applications to investigate the species' potential to perform bioremediation of NP-contaminated wastewater and explore the mechanism of NP toxicity in algal cell. The algal species exhibited a high tolerance for NP and efficiently removed even high concentrations of NP. The accumulation of NP in algal cells tended to increase and the percentage of NP adhered to the cell walls tended to decrease as the NP concentration increased. The thylakoid density and the pyrenoid size also tended to decrease as the NP concentration rose. The key genes involved in the antioxidative pathways and photosynthetic pathways were down-regulated in the NP-treated algal cells. Algal ribosome genes were especially sensitive to NP. The results indicated that NP could induce oxidative stress in algal cells and that Dictyosphaerium sp. showed potential as a bioremediation agent.
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Affiliation(s)
- Qilu Cheng
- College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Qifa Zhou
- College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Zhuo Jin
- College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Ying Jiang
- College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Ligen Xu
- College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Hui Jiang
- College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yuhua Zhao
- College of Life Sciences, Zhejiang University, Hangzhou 310058, China.
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17
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Nucleolus structural integrity during the first meiotic prophase in rat spermatocytes. Exp Cell Res 2019; 383:111587. [PMID: 31454492 DOI: 10.1016/j.yexcr.2019.111587] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 08/22/2019] [Accepted: 08/23/2019] [Indexed: 12/19/2022]
Abstract
A typical nucleolus structure is shaped by three components. A meshwork of fine fibers forming the fibrillar center (FC) is surrounded by densely packed fibers forming the dense fibrillar component (DFC). Meanwhile, wrapping the FC and DFC is the granular component (GC). During the mitotic prophase, the nucleolus undergoes disassembling of its components. On the contrary, throughout the first meiotic prophase that occurs in the cells of the germ line, small nucleoli are assembled into one nucleolus by the end of the prophase. These nucleoli are transcriptionally active, suggesting that they are fully functional. Electron microscopy analysis has suggested that these nucleoli display their three main components but a typical organization has not been observed. Here, by immunolabeling and electron microscopy, we show that the nucleolus has its three main components. The GC is interlaced with the DFC and is not as well defined as previously thought during leptotene and zygotene stage.
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18
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Controlling the material properties and rRNA processing function of the nucleolus using light. Proc Natl Acad Sci U S A 2019; 116:17330-17335. [PMID: 31399547 DOI: 10.1073/pnas.1903870116] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The nucleolus is a prominent nuclear condensate that plays a central role in ribosome biogenesis by facilitating the transcription and processing of nascent ribosomal RNA (rRNA). A number of studies have highlighted the active viscoelastic nature of the nucleolus, whose material properties and phase behavior are a consequence of underlying molecular interactions. However, the ways in which the material properties of the nucleolus impact its function in rRNA biogenesis are not understood. Here we utilize the Cry2olig optogenetic system to modulate the viscoelastic properties of the nucleolus. We show that above a threshold concentration of Cry2olig protein, the nucleolus can be gelled into a tightly linked, low mobility meshwork. Gelled nucleoli no longer coalesce and relax into spheres but nonetheless permit continued internal molecular mobility of small proteins. These changes in nucleolar material properties manifest in specific alterations in rRNA processing steps, including a buildup of larger rRNA precursors and a depletion of smaller rRNA precursors. We propose that the flux of processed rRNA may be actively tuned by the cell through modulating nucleolar material properties, which suggests the potential of materials-based approaches for therapeutic intervention in ribosomopathies.
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19
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Liu X, Cai S, Zhang C, Liu Z, Luo J, Xing B, Du X. Deacetylation of NAT10 by Sirt1 promotes the transition from rRNA biogenesis to autophagy upon energy stress. Nucleic Acids Res 2019; 46:9601-9616. [PMID: 30165671 PMCID: PMC6182161 DOI: 10.1093/nar/gky777] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 08/17/2018] [Indexed: 02/06/2023] Open
Abstract
Anabolism and catabolism are tightly regulated according to the cellular energy supply. Upon energy stress, ribosomal RNA (rRNA) biogenesis is inhibited, and autophagy is induced. However, the mechanism linking rRNA biogenesis and autophagy is unclear. Here, we demonstrate that the nucleolar protein NAT10 plays a role in the transition between rRNA biogenesis and autophagy. Under normal conditions, NAT10 is acetylated to activate rRNA biogenesis and inhibit autophagy induction. Mechanistic studies demonstrate that NAT10 binds to and acetylates the autophagy regulator Che-1 at K228 to suppress the Che-1-mediated transcriptional activation of downstream genes Redd1 and Deptor under adequate energy supply conditions. Upon energy stress, NAT10 is deacetylated by Sirt1, leading to suppression of NAT10-activated rRNA biogenesis. In addition, deacetylation of NAT10 abolishes the NAT10-mediated transcriptional repression of Che-1, leading to the release of autophagy inhibition. Collectively, we demonstrate that the acetylation status of NAT10 is important for the anabolism-catabolism transition in response to energy stress, providing a novel mechanism by which nucleolar proteins control rRNA synthesis and autophagy in response to the cellular energy supply.
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Affiliation(s)
- Xiaofeng Liu
- Hepatopancreatobiliary Surgery Department I, Key laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Peking University Cancer Hospital & Institute, Beijing 100142, China
| | - Shiying Cai
- Department of Cell Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Chunfeng Zhang
- Department of Medical Genetics, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Zhenzhen Liu
- Hepatopancreatobiliary Surgery Department I, Key laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Peking University Cancer Hospital & Institute, Beijing 100142, China
| | - Jianyuan Luo
- Department of Medical Genetics, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Baocai Xing
- Hepatopancreatobiliary Surgery Department I, Key laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Peking University Cancer Hospital & Institute, Beijing 100142, China
| | - Xiaojuan Du
- Department of Cell Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
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20
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Piazzi M, Bavelloni A, Gallo A, Faenza I, Blalock WL. Signal Transduction in Ribosome Biogenesis: A Recipe to Avoid Disaster. Int J Mol Sci 2019; 20:ijms20112718. [PMID: 31163577 PMCID: PMC6600399 DOI: 10.3390/ijms20112718] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 05/29/2019] [Accepted: 05/30/2019] [Indexed: 12/27/2022] Open
Abstract
Energetically speaking, ribosome biogenesis is by far the most costly process of the cell and, therefore, must be highly regulated in order to avoid unnecessary energy expenditure. Not only must ribosomal RNA (rRNA) synthesis, ribosomal protein (RP) transcription, translation, and nuclear import, as well as ribosome assembly, be tightly controlled, these events must be coordinated with other cellular events, such as cell division and differentiation. In addition, ribosome biogenesis must respond rapidly to environmental cues mediated by internal and cell surface receptors, or stress (oxidative stress, DNA damage, amino acid depletion, etc.). This review examines some of the well-studied pathways known to control ribosome biogenesis (PI3K-AKT-mTOR, RB-p53, MYC) and how they may interact with some of the less well studied pathways (eIF2α kinase and RNA editing/splicing) in higher eukaryotes to regulate ribosome biogenesis, assembly, and protein translation in a dynamic manner.
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Affiliation(s)
- Manuela Piazzi
- Istituto di Genetica Molecolare-Luigi Luca Cavalli Sforza, UOS Bologna, Consiglio Nazionale delle Ricerche (IGM-CNR), 40136 Bologna, Italy.
- IRCCS, Istituto Ortopedico Rizzoli, 40136 Bologna, Italy.
| | | | - Angela Gallo
- RNA Editing Laboratory, Dipartimento di Oncoematologia, IRCCS, Ospedale Pediatrica Bambino Gesù, 00146 Rome, Italy.
| | - Irene Faenza
- Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, 40126 Bologna, Italy.
| | - William L Blalock
- Istituto di Genetica Molecolare-Luigi Luca Cavalli Sforza, UOS Bologna, Consiglio Nazionale delle Ricerche (IGM-CNR), 40136 Bologna, Italy.
- IRCCS, Istituto Ortopedico Rizzoli, 40136 Bologna, Italy.
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21
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Šašinková M, Holoubek A, Otevřelová P, Kuželová K, Brodská B. AML-associated mutation of nucleophosmin compromises its interaction with nucleolin. Int J Biochem Cell Biol 2018; 103:65-73. [PMID: 30130654 DOI: 10.1016/j.biocel.2018.08.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 08/15/2018] [Accepted: 08/16/2018] [Indexed: 11/17/2022]
Abstract
C-terminal mutations of the nucleolar protein nucleophosmin (NPM) are the most frequent genetic aberration detected in acute myeloid leukemia (AML) with normal karyotype. The mutations cause aberrant cytoplasmic localization of NPM and lead to loss of functions associated with NPM nucleolar localization, e.g. in ribosome biogenesis or DNA-damage repair. NPM has many interaction partners and some of them were proved to interact also with the mutated form (NPMmut) and due to this interaction thereby to be withdrawn from their site of action. We analyzed the impact of the mutation on NPM interaction with nucleolin (NCL) which is also prevalently localized into the nucleolus and cooperates with wild-type NPM (NPMwt) in many cellular processes. We revealed that the NCL-NPM complex formation is completely abolished by the mutation and that the presence/absence of the interaction is not affected by drugs causing genotoxic stress or differentiation. Deregulation resulting from changes of NCL/NPMwt ratio may contribute to leukemogenesis.
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Affiliation(s)
- Markéta Šašinková
- Institute of Hematology and Blood Transfusion, U Nemocnice 1, 128 20 Prague 2, Czech Republic
| | - Aleš Holoubek
- Institute of Hematology and Blood Transfusion, U Nemocnice 1, 128 20 Prague 2, Czech Republic
| | - Petra Otevřelová
- Institute of Hematology and Blood Transfusion, U Nemocnice 1, 128 20 Prague 2, Czech Republic
| | - Kateřina Kuželová
- Institute of Hematology and Blood Transfusion, U Nemocnice 1, 128 20 Prague 2, Czech Republic
| | - Barbora Brodská
- Institute of Hematology and Blood Transfusion, U Nemocnice 1, 128 20 Prague 2, Czech Republic.
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22
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Sen Gupta A, Sengupta K. Lamin B2 Modulates Nucleolar Morphology, Dynamics, and Function. Mol Cell Biol 2017; 37:e00274-17. [PMID: 28993479 PMCID: PMC5705821 DOI: 10.1128/mcb.00274-17] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Revised: 07/05/2017] [Accepted: 09/29/2017] [Indexed: 01/11/2023] Open
Abstract
The nucleolus is required for ribosome biogenesis. Human cells have 2 or 3 nucleoli associated with nucleolar organizer region (NOR)-bearing chromosomes. An increase in number and altered nucleolar morphology define cancer cells. However, the mechanisms that modulate nucleolar morphology and function are unclear. Here we show that in addition to localizing at the nuclear envelope, lamin B2 localizes proximal to nucleolin at the granular component (GC) of the nucleolus and associates with the nucleolar proteins nucleolin and nucleophosmin. Lamin B2 knockdown severely disrupted the nucleolar morphology, which was rescued to intact and discrete nucleoli upon lamin B2 overexpression. Furthermore, two mutually exclusive lamin B2 deletion mutants, ΔHead and ΔSLS, rescued nuclear and nucleolar morphology defects, respectively, induced upon lamin B2 depletion, suggesting independent roles for lamin B2 at the nucleolus and nuclear envelope. Lamin B2 depletion increased nucleolin aggregation in the nucleoplasm, implicating lamin B2 in stabilizing nucleolin within the nucleolus. Lamin B2 knockdown upregulated nucleolus-specific 45S rRNA and upstream intergenic sequence (IGS) transcripts. The IGS transcripts colocalized with aggregates of nucleolin speckles, which were sustained in the nucleoplasm upon lamin B2 depletion. Taken together, these studies uncover a novel role for lamin B2 in modulating the morphology, dynamics, and function of the nucleolus.
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Affiliation(s)
- Ayantika Sen Gupta
- Biology, Indian Institute of Science Education and Research, Pune, India
| | - Kundan Sengupta
- Biology, Indian Institute of Science Education and Research, Pune, India
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Justilien V, Lewis KC, Murray NR, Fields AP. Oncogenic Ect2 signaling regulates rRNA synthesis in NSCLC. Small GTPases 2017; 10:388-394. [PMID: 28657426 DOI: 10.1080/21541248.2017.1335274] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Abstract
The Rho GTPase family members Rac1, Cdc42 and RhoA play key contributory roles in the transformed phenotype of human cancers. Epithelial Cell Transforming Sequence 2 (Ect2), a guanine nucleotide exchange factor (GEF) for these Rho GTPases, has also been implicated in a variety of human cancers. We have shown that Ect2 is frequently overexpressed in both major forms of non-small cell lung cancer (NSCLC), lung adenocarcinoma (LADC) and lung squamous cell carcinoma (LSCC), which together make up approximately 70% of all lung cancer diagnoses. Furthermore, we have found that Ect2 is required for multiple aspects of the transformed phenotype of NSCLC cells including transformed growth and invasion in vitro and tumorigenesis in vivo. More recently, we showed that a major mechanism by which Ect2 drives KRAS-mediated LADC transformation is by regulating rRNA (rRNA) synthesis. However, it remains unclear whether Ect2 plays a similar role in ribosome biogenesis in LSCC. Here we demonstrate that Ect2 expression correlates positively with expression of ribosome biogenesis genes and with pre-ribosomal 45S RNA abundance in primary LSCC tumors. Furthermore, we demonstrate that Ect2 functionally regulates rRNA synthesis in LSCC cells. Based on these data, we propose that inhibition of Ect2-mediated nucleolar signaling holds promise as a potential therapeutic strategy for improved treatment of both LADC and LSCC.
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Affiliation(s)
- Verline Justilien
- a Department of Cancer Biology, Mayo Clinic Comprehensive Cancer Center , Jacksonville , FL , USA
| | - Kayla C Lewis
- a Department of Cancer Biology, Mayo Clinic Comprehensive Cancer Center , Jacksonville , FL , USA
| | - Nicole R Murray
- a Department of Cancer Biology, Mayo Clinic Comprehensive Cancer Center , Jacksonville , FL , USA
| | - Alan P Fields
- a Department of Cancer Biology, Mayo Clinic Comprehensive Cancer Center , Jacksonville , FL , USA
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The Potential of Targeting Ribosome Biogenesis in High-Grade Serous Ovarian Cancer. Int J Mol Sci 2017; 18:ijms18010210. [PMID: 28117679 PMCID: PMC5297839 DOI: 10.3390/ijms18010210] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 01/07/2017] [Accepted: 01/12/2017] [Indexed: 02/06/2023] Open
Abstract
Overall survival for patients with ovarian cancer (OC) has shown little improvement for decades meaning new therapeutic options are critical. OC comprises multiple histological subtypes, of which the most common and aggressive subtype is high-grade serous ovarian cancer (HGSOC). HGSOC is characterized by genomic structural variations with relatively few recurrent somatic mutations or dominantly acting oncogenes that can be targeted for the development of novel therapies. However, deregulation of pathways controlling homologous recombination (HR) and ribosome biogenesis has been observed in a high proportion of HGSOC, raising the possibility that targeting these basic cellular processes may provide improved patient outcomes. The poly (ADP-ribose) polymerase (PARP) inhibitor olaparib has been approved to treat women with defects in HR due to germline BRCA mutations. Recent evidence demonstrated the efficacy of targeting ribosome biogenesis with the specific inhibitor of ribosomal RNA synthesis, CX-5461 in v-myc avian myelocytomatosis viral oncogene homolog (MYC)-driven haematological and prostate cancers. CX-5461 has now progressed to a phase I clinical trial in patients with haematological malignancies and phase I/II trial in breast cancer. Here we review the currently available targeted therapies for HGSOC and discuss the potential of targeting ribosome biogenesis as a novel therapeutic approach against HGSOC.
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Achiron A, Zilkha-Falb R, Mashiach R, Gurevich M. RAM-589.555 a new Polymerase-1 inhibitor as innovative targeted-treatment for multiple sclerosis. J Neuroimmunol 2017; 302:41-48. [DOI: 10.1016/j.jneuroim.2016.10.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Revised: 10/25/2016] [Accepted: 10/30/2016] [Indexed: 01/16/2023]
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Rosato M, Kovařík A, Garilleti R, Rosselló JA. Conserved Organisation of 45S rDNA Sites and rDNA Gene Copy Number among Major Clades of Early Land Plants. PLoS One 2016; 11:e0162544. [PMID: 27622766 PMCID: PMC5021289 DOI: 10.1371/journal.pone.0162544] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Accepted: 08/24/2016] [Indexed: 11/26/2022] Open
Abstract
Genes encoding ribosomal RNA (rDNA) are universal key constituents of eukaryotic genomes, and the nuclear genome harbours hundreds to several thousand copies of each species. Knowledge about the number of rDNA loci and gene copy number provides information for comparative studies of organismal and molecular evolution at various phylogenetic levels. With the exception of seed plants, the range of 45S rDNA locus (encoding 18S, 5.8S and 26S rRNA) and gene copy number variation within key evolutionary plant groups is largely unknown. This is especially true for the three earliest land plant lineages Marchantiophyta (liverworts), Bryophyta (mosses), and Anthocerotophyta (hornworts). In this work, we report the extent of rDNA variation in early land plants, assessing the number of 45S rDNA loci and gene copy number in 106 species and 25 species, respectively, of mosses, liverworts and hornworts. Unexpectedly, the results show a narrow range of ribosomal locus variation (one or two 45S rDNA loci) and gene copies not present in vascular plant lineages, where a wide spectrum is recorded. Mutation analysis of whole genomic reads showed higher (3-fold) intragenomic heterogeneity of Marchantia polymorpha (Marchantiophyta) rDNA compared to Physcomitrella patens (Bryophyta) and two angiosperms (Arabidopsis thaliana and Nicotiana tomentosifomis) suggesting the presence of rDNA pseudogenes in its genome. No association between phylogenetic position, taxonomic adscription and the number of rDNA loci and gene copy number was found. Our results suggest a likely evolutionary rDNA stasis during land colonisation and diversification across 480 myr of bryophyte evolution. We hypothesise that strong selection forces may be acting against ribosomal gene locus amplification. Despite showing a predominant haploid phase and infrequent meiosis, overall rDNA homogeneity is not severely compromised in bryophytes.
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Affiliation(s)
- Marcela Rosato
- Jardín Botánico, ICBiBE-Unidad Asociada CSIC, Universidad de Valencia, c/Quart 80, E-46008, Valencia, Spain
| | - Aleš Kovařík
- Institute of Biophysics, Academy of Sciences of the Czech Republic, Brno, CZ–61265, Czech Republic
| | - Ricardo Garilleti
- Departamento de Botánica, Facultad de Farmacia, Universidad de Valencia, E-46100, Burjassot, Spain
| | - Josep A. Rosselló
- Jardín Botánico, ICBiBE-Unidad Asociada CSIC, Universidad de Valencia, c/Quart 80, E-46008, Valencia, Spain
- Marimurtra Bot. Garden, Carl Faust Fdn., PO Box 112, E-17300, Blanes, Catalonia, Spain
- * E-mail:
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Nardocci G, Simonet NG, Navarro C, Längst G, Alvarez M. Differential enrichment of TTF-I and Tip5 in the T-like promoter structures of the rDNA contribute to the epigenetic response of Cyprinus carpio during environmental adaptation. Biochem Cell Biol 2016; 94:315-21. [PMID: 27458840 DOI: 10.1139/bcb-2016-0015] [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] [Indexed: 12/19/2022] Open
Abstract
To ensure homeostasis, ectothermic organisms adapt to environmental variations through molecular mechanisms. We previously reported that during the seasonal acclimatization of the common carp Cyprinus carpio, molecular and cellular functions are reprogrammed, resulting in distinctive traits. Importantly, the carp undergoes a drastic rearrangement of nucleolar components during adaptation. This ultrastructural feature reflects a fine modulation of rRNA gene transcription. Specifically, we identified the involvement of the transcription termination factor I (TTF-I) and Tip-5 (member of nucleolar remodeling complex, NoRC) in the control of rRNA transcription. Our results suggest that differential Tip5 enrichment is essential for silencing carp ribosomal genes and that the T0 element is key for regulating the ribosomal gene during the acclimatization process. Interestingly, the expression and content of Tip5 were significantly higher in winter than in summer. Since carp ribosomal gene expression is lower in the winter than in summer, and considering that expression concomitantly occurs with nucleolar ultrastructural changes of the acclimatization process, these results indicate that Tip5 importantly contributes to silencing the ribosomal genes. In conclusion, the current study provides novel evidence on the contributions of TTF-I and NoRC in the environmental reprogramming of ribosomal genes during the seasonal adaptation process in carp.
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Affiliation(s)
- Gino Nardocci
- a Laboratorio de Biología Celular y Molecular, Departamento de Ciencias Biológicas, Facultad de Ciencias Biológicas, Universidad Andrés Bello, Quillota 980, Viña del Mar, Chile
| | - Nicolas G Simonet
- a Laboratorio de Biología Celular y Molecular, Departamento de Ciencias Biológicas, Facultad de Ciencias Biológicas, Universidad Andrés Bello, Quillota 980, Viña del Mar, Chile
| | - Cristina Navarro
- b Laboratorio de Biotecnología Molecular, Departamento de Ciencias Biológicas, Facultad de Ciencias Biológicas, Universidad Andrés Bello, Avenida Republica 217, Santiago, Chile
| | - Gernot Längst
- c Institute for Biochemistry III, Biochemie-Zentrum Regensburg, University of Regensburg, Regensburg, Germany
| | - Marco Alvarez
- a Laboratorio de Biología Celular y Molecular, Departamento de Ciencias Biológicas, Facultad de Ciencias Biológicas, Universidad Andrés Bello, Quillota 980, Viña del Mar, Chile.,d Interdisciplinary Center for Aquaculture Research (INCAR), Victor Lamas 1290, PO Box 160-C, Concepción, Chile
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Li J, Qin S, Yu H, Zhang J, Liu N, Yu Y, Hou C, Li M. Comparative Transcriptome Analysis Reveals Different Silk Yields of Two Silkworm Strains. PLoS One 2016; 11:e0155329. [PMID: 27159277 PMCID: PMC4861282 DOI: 10.1371/journal.pone.0155329] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 04/27/2016] [Indexed: 12/17/2022] Open
Abstract
Cocoon and silk yields are the most important characteristics of sericulture. However, few studies have examined the genes that modulate these features. Further studies of these genes will be useful for improving the products of sericulture. JingSong (JS) and Lan10 (L10) are two strains having significantly different cocoon and silk yields. In the current study, RNA-Seq and quantitative polymerase chain reaction (qPCR) were performed on both strains in order to determine divergence of the silk gland, which controls silk biosynthesis in silkworms. Compared with L10, JS had 1375 differentially expressed genes (DEGs; 738 up-regulated genes and 673 down-regulated genes). Nine enriched gene ontology (GO) terms were identified by GO enrichment analysis based on these DEGs. KEGG enrichment analysis results showed that the DEGs were enriched in three pathways, which were mainly associated with the processing and biosynthesis of proteins. The representative genes in the enrichment pathways and ten significant DEGs were further verified by qPCR, the results of which were consistent with the RNA-Seq data. Our study has revealed differences in silk glands between the two silkworm strains and provides a perspective for understanding the molecular mechanisms determining silk yield.
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Affiliation(s)
- Juan Li
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang Jiangsu 212018, China
| | - Sheng Qin
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang Jiangsu 212018, China
- The Sericultural Research Institute, Chinese Academy of Agricultural Science, Zhenjiang Jiangsu 212018, China
| | - Huanjun Yu
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang Jiangsu 212018, China
| | - Jing Zhang
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang Jiangsu 212018, China
| | - Na Liu
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang Jiangsu 212018, China
| | - Ye Yu
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang Jiangsu 212018, China
| | - Chengxiang Hou
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang Jiangsu 212018, China
- The Sericultural Research Institute, Chinese Academy of Agricultural Science, Zhenjiang Jiangsu 212018, China
| | - Muwang Li
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang Jiangsu 212018, China
- The Sericultural Research Institute, Chinese Academy of Agricultural Science, Zhenjiang Jiangsu 212018, China
- * E-mail:
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29
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Petrova A, Moffett DF. Comprehensive Immunolocalization Studies of a Putative Serotonin Receptor from the Alimentary Canal of Aedes aegypti Larvae Suggest Its Diverse Roles in Digestion and Homeostasis. PLoS One 2016; 11:e0146587. [PMID: 26808995 PMCID: PMC4726579 DOI: 10.1371/journal.pone.0146587] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Accepted: 12/18/2015] [Indexed: 11/17/2022] Open
Abstract
Serotonin regulates key processes including digestion and homeostasis in insects. Serotonin effects are mediated by serotonin receptors that transduce information through initiation of second messenger signaling pathways. Lack of information on serotonin receptors associated with the alimentary canal impedes the understanding of the serotonergic role in insect physiology. To address this void, the present study has cloned and identified a putative serotonin receptor (hereafter AaSeR-1) from the alimentary canal of Aedes aegypti (yellow fever mosquito) larvae. In addition to in-silico analyses of AaSeR-1 primary sequence, immunohistochemical investigations were carried out to elucidate receptor expression patterns. Specific AaSeR-1 immunofluorescence was detected in the caeca, the mid- and hindgut, including the Malpighian tubules. These findings point out not only receptor ubiquitous nature but also its involvement in regulation of different stages of nutrient processing and homeostasis. Furthermore, AaSeR-1 may mediate an array of effects through its differential expression at various cell compartments. While AaSeR-1 specific immunofluorescence was depicted in the nucleus and nucleolus of principal cells of the anterior midgut, in the posterior, analyses suggest receptor association with the plasma membrane of both principal and regenerative cells. In addition, AaSeR-1 immunofluorescence was also found in some enteroendocrine cells and in both circular and longitudinal muscles that innervate the alimentary canal. Overall, immunohistochemical analyses of AaSeR-1 expression indicate that this receptor exercises multiple roles in digestion- and homeostasis-related mechanisms.
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Affiliation(s)
- Adelina Petrova
- School of Biological Sciences, Washington State University, Pullman, WA, United States of America
| | - David Franklin Moffett
- School of Biological Sciences, Washington State University, Pullman, WA, United States of America
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30
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Sakai D, Dixon J, Achilleos A, Dixon M, Trainor PA. Prevention of Treacher Collins syndrome craniofacial anomalies in mouse models via maternal antioxidant supplementation. Nat Commun 2016; 7:10328. [PMID: 26792133 PMCID: PMC4735750 DOI: 10.1038/ncomms10328] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Accepted: 12/02/2015] [Indexed: 12/25/2022] Open
Abstract
Craniofacial anomalies account for approximately one-third of all birth defects and are a significant cause of infant mortality. Since the majority of the bones, cartilage and connective tissues that comprise the head and face are derived from a multipotent migratory progenitor cell population called the neural crest, craniofacial disorders are typically attributed to defects in neural crest cell development. Treacher Collins syndrome (TCS) is a disorder of craniofacial development and although TCS arises primarily through autosomal dominant mutations in TCOF1, no clear genotype-phenotype correlation has been documented. Here we show that Tcof1 haploinsufficiency results in oxidative stress-induced DNA damage and neuroepithelial cell death. Consistent with this discovery, maternal treatment with antioxidants minimizes cell death in the neuroepithelium and substantially ameliorates or prevents the pathogenesis of craniofacial anomalies in Tcof1(+/-) mice. Thus maternal antioxidant dietary supplementation may provide an avenue for protection against the pathogenesis of TCS and similar neurocristopathies.
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Affiliation(s)
- Daisuke Sakai
- Organization for Research Initiatives and Development, Doshisha University, Karasuma Higashi-iru, Imadegawa-dori, Kamigyo, Kyoto 602-8580, Japan
| | - Jill Dixon
- Dental School, Faculty of Medical and Human Sciences, Manchester Academic Health Sciences Centre, Michael Smith Building, University of Manchester, Oxford Road, Manchester M13 9PT, UK
| | - Annita Achilleos
- Stowers Institute for Medical Research, 1000 E. 50th Street, Kansas City, Missouri 64110, USA
| | - Michael Dixon
- Dental School, Faculty of Medical and Human Sciences, Manchester Academic Health Sciences Centre, Michael Smith Building, University of Manchester, Oxford Road, Manchester M13 9PT, UK
- Faculty of Life Sciences, Michael Smith Building, University of Manchester, Oxford Road, Manchester M13 9PT, UK
| | - Paul A. Trainor
- Stowers Institute for Medical Research, 1000 E. 50th Street, Kansas City, Missouri 64110, USA
- Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, Kansas 66160, USA
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31
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Davis WJ, Lehmann PZ, Li W. Nuclear PI3K signaling in cell growth and tumorigenesis. Front Cell Dev Biol 2015; 3:24. [PMID: 25918701 PMCID: PMC4394695 DOI: 10.3389/fcell.2015.00024] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2014] [Accepted: 03/27/2015] [Indexed: 12/12/2022] Open
Abstract
The PI3K/Akt signaling pathway is a major driving force in a variety of cellular functions. Dysregulation of this pathway has been implicated in many human diseases including cancer. While the activity of the cytoplasmic PI3K/Akt pathway has been extensively studied, the functions of these molecules and their effector proteins within the nucleus are poorly understood. Harboring key cellular processes such as DNA replication and repair as well as nascent messenger RNA transcription, the nucleus provides a unique compartmental environment for protein–protein and protein–DNA/RNA interactions required for cell survival, growth, and proliferation. Here we summarize recent advances made toward elucidating the nuclear PI3K/Akt signaling cascade and its key components within the nucleus as they pertain to cell growth and tumorigenesis. This review covers the spatial and temporal localization of the major nuclear kinases having PI3K activities and the counteracting phosphatases as well as the role of nuclear PI3K/Akt signaling in mRNA processing and exportation, DNA replication and repair, ribosome biogenesis, cell survival, and tumorigenesis.
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Affiliation(s)
- William J Davis
- College of Medical Sciences, Washington State University Spokane, WA, USA
| | - Peter Z Lehmann
- College of Medical Sciences, Washington State University Spokane, WA, USA
| | - Weimin Li
- College of Medical Sciences, Washington State University Spokane, WA, USA
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32
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Ryu KW, Kim DS, Kraus WL. New facets in the regulation of gene expression by ADP-ribosylation and poly(ADP-ribose) polymerases. Chem Rev 2015; 115:2453-81. [PMID: 25575290 PMCID: PMC4378458 DOI: 10.1021/cr5004248] [Citation(s) in RCA: 107] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Indexed: 12/11/2022]
Affiliation(s)
- Keun Woo Ryu
- Laboratory of Signaling and Gene
Regulation, Cecil H. and Ida Green
Center for Reproductive Biology Sciences, Division of Basic Research, Department
of Obstetrics and Gynecology, and Graduate School of Biomedical Sciences, Program
in Genetics and Development, University
of Texas Southwestern Medical Center, Dallas, Texas 75390, United States
| | - Dae-Seok Kim
- Laboratory of Signaling and Gene
Regulation, Cecil H. and Ida Green
Center for Reproductive Biology Sciences, Division of Basic Research, Department
of Obstetrics and Gynecology, and Graduate School of Biomedical Sciences, Program
in Genetics and Development, University
of Texas Southwestern Medical Center, Dallas, Texas 75390, United States
| | - W. Lee Kraus
- Laboratory of Signaling and Gene
Regulation, Cecil H. and Ida Green
Center for Reproductive Biology Sciences, Division of Basic Research, Department
of Obstetrics and Gynecology, and Graduate School of Biomedical Sciences, Program
in Genetics and Development, University
of Texas Southwestern Medical Center, Dallas, Texas 75390, United States
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Diesch J, Hannan RD, Sanij E. Perturbations at the ribosomal genes loci are at the centre of cellular dysfunction and human disease. Cell Biosci 2014; 4:43. [PMID: 25949792 PMCID: PMC4422213 DOI: 10.1186/2045-3701-4-43] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2014] [Accepted: 07/27/2014] [Indexed: 01/05/2023] Open
Abstract
Ribosomal RNA (rRNA) gene (rDNA) transcription by RNA Polymerase I (Pol I) drives cell growth and underlies nucleolar structure and function, indirectly coordinating many fundamental cellular processes. The importance of keeping rDNA transcription under tight control is reflected by the fact that deranged Pol I transcription is a feature of cancer and other human disorders. In this review, we discuss multiple aspects of rDNA function including the relationship between Pol I transcription and proliferative capacity, the role of Pol I transcription in mediating nucleolar structure and integrity, and rDNA/nucleolar interactions with the genome and their influence on heterochromatin and global genome stability. Furthermore, we discuss how perturbations in the structure of the rDNA loci might contribute to human disease, in some cases independent of effects on ribosome biogenesis.
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Affiliation(s)
- Jeannine Diesch
- Growth Control Laboratory, Research Division, Peter MacCallum Cancer Centre, St. Andrews Place, East Melbourne, Victoria 3002, Australia ; Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Ross D Hannan
- Growth Control Laboratory, Research Division, Peter MacCallum Cancer Centre, St. Andrews Place, East Melbourne, Victoria 3002, Australia ; Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria 3010, Australia ; Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia ; Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Victoria 3010, Australia ; Division of Cancer Medicine, Peter MacCallum Cancer Centre, St. Andrews Place, East Melbourne, Victoria 3002, Australia ; School of Biomedical Sciences, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Elaine Sanij
- Growth Control Laboratory, Research Division, Peter MacCallum Cancer Centre, St. Andrews Place, East Melbourne, Victoria 3002, Australia ; Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria 3010, Australia ; Department of Pathology, University of Melbourne, Parkville, Victoria 3010, Australia
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Golomb L, Volarevic S, Oren M. p53 and ribosome biogenesis stress: the essentials. FEBS Lett 2014; 588:2571-9. [PMID: 24747423 DOI: 10.1016/j.febslet.2014.04.014] [Citation(s) in RCA: 166] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2014] [Revised: 04/04/2014] [Accepted: 04/04/2014] [Indexed: 12/18/2022]
Abstract
Cell proliferation and cell growth are two tightly linked processes, as the proliferation program cannot be executed without proper accumulation of cell mass, otherwise endangering the fate of the two daughter cells. It is therefore not surprising that ribosome biogenesis, a key element in cell growth, is regulated by many cell cycle regulators. This regulation is exerted transcriptionally and post-transcriptionally, in conjunction with numerous intrinsic and extrinsic signals. Those signals eventually converge at the nucleolus, the cellular compartment that is not only responsible for executing the ribosome biogenesis program, but also serves as a regulatory hub, responsible for integrating and transmitting multiple stress signals to the omnipotent cell fate gatekeeper, p53. In this review we discuss when, how and why p53 is activated upon ribosomal biogenesis stress, and how perturbation of this critical regulatory interplay may impact human disease.
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Affiliation(s)
- Lior Golomb
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Sinisa Volarevic
- Department of Molecular Medicine and Biotechnology, School of Medicine, University of Rijeka, Croatia
| | - Moshe Oren
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot, Israel.
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35
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Maggi LB, Winkeler CL, Miceli AP, Apicelli AJ, Brady SN, Kuchenreuther MJ, Weber JD. ARF tumor suppression in the nucleolus. Biochim Biophys Acta Mol Basis Dis 2014; 1842:831-9. [PMID: 24525025 DOI: 10.1016/j.bbadis.2014.01.016] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Revised: 01/27/2014] [Accepted: 01/28/2014] [Indexed: 02/06/2023]
Abstract
Since its discovery close to twenty years ago, the ARF tumor suppressor has played a pivotal role in the field of cancer biology. Elucidating ARF's basal physiological function in the cell has been the focal interest of numerous laboratories throughout the world for many years. Our current understanding of ARF is constantly evolving to include novel frameworks for conceptualizing the regulation of this critical tumor suppressor. As a result of this complexity, there is great need to broaden our understanding of the intricacies governing the biology of the ARF tumor suppressor. The ARF tumor suppressor is a key sensor of signals that instruct a cell to grow and proliferate and is appropriately localized in nucleoli to limit these processes. This article is part of a Special Issue entitled: Role of the Nucleolus in Human Disease.
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Affiliation(s)
- Leonard B Maggi
- BRIGHT Institute, Department of Internal Medicine, Division of Molecular Oncology, Siteman Cancer Center, Washington University School of Medicine, Saint Louis, MO, USA
| | - Crystal L Winkeler
- BRIGHT Institute, Department of Internal Medicine, Division of Molecular Oncology, Siteman Cancer Center, Washington University School of Medicine, Saint Louis, MO, USA
| | - Alexander P Miceli
- BRIGHT Institute, Department of Internal Medicine, Division of Molecular Oncology, Siteman Cancer Center, Washington University School of Medicine, Saint Louis, MO, USA
| | - Anthony J Apicelli
- BRIGHT Institute, Department of Internal Medicine, Division of Molecular Oncology, Siteman Cancer Center, Washington University School of Medicine, Saint Louis, MO, USA
| | - Suzanne N Brady
- BRIGHT Institute, Department of Internal Medicine, Division of Molecular Oncology, Siteman Cancer Center, Washington University School of Medicine, Saint Louis, MO, USA
| | - Michael J Kuchenreuther
- BRIGHT Institute, Department of Internal Medicine, Division of Molecular Oncology, Siteman Cancer Center, Washington University School of Medicine, Saint Louis, MO, USA
| | - Jason D Weber
- BRIGHT Institute, Department of Internal Medicine, Division of Molecular Oncology, Siteman Cancer Center, Washington University School of Medicine, Saint Louis, MO, USA.
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Peltonen K, Colis L, Liu H, Trivedi R, Moubarek MS, Moore HM, Bai B, Rudek MA, Bieberich CJ, Laiho M. A targeting modality for destruction of RNA polymerase I that possesses anticancer activity. Cancer Cell 2014; 25:77-90. [PMID: 24434211 PMCID: PMC3930145 DOI: 10.1016/j.ccr.2013.12.009] [Citation(s) in RCA: 195] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Revised: 10/03/2013] [Accepted: 12/16/2013] [Indexed: 01/07/2023]
Abstract
We define the activity and mechanisms of action of a small molecule lead compound for cancer targeting. We show that the compound, BMH-21, has wide and potent antitumorigenic activity across NCI60 cancer cell lines and represses tumor growth in vivo. BMH-21 binds GC-rich sequences, which are present at a high frequency in ribosomal DNA genes, and potently and rapidly represses RNA polymerase I (Pol I) transcription. Strikingly, we find that BMH-21 causes proteasome-dependent destruction of RPA194, the large catalytic subunit protein of Pol I holocomplex, and this correlates with cancer cell killing. Our results show that Pol I activity is under proteasome-mediated control, which reveals an unexpected therapeutic opportunity.
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Affiliation(s)
- Karita Peltonen
- Molecular Cancer Biology Program and Centre for Drug Research, University of Helsinki, Helsinki 00014, Finland
| | - Laureen Colis
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA
| | - Hester Liu
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA
| | - Rishi Trivedi
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA
| | - Michael S Moubarek
- Department of Biological Sciences, University of Maryland Baltimore County, Baltimore, MD 21250, USA
| | - Henna M Moore
- Molecular Cancer Biology Program and Centre for Drug Research, University of Helsinki, Helsinki 00014, Finland
| | - Baoyan Bai
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA
| | - Michelle A Rudek
- Department of Oncology and The Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA
| | - Charles J Bieberich
- Department of Biological Sciences, University of Maryland Baltimore County, Baltimore, MD 21250, USA
| | - Marikki Laiho
- Molecular Cancer Biology Program and Centre for Drug Research, University of Helsinki, Helsinki 00014, Finland; Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA; Department of Oncology and The Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA.
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Quin JE, Devlin JR, Cameron D, Hannan KM, Pearson RB, Hannan RD. Targeting the nucleolus for cancer intervention. Biochim Biophys Acta Mol Basis Dis 2014; 1842:802-16. [PMID: 24389329 DOI: 10.1016/j.bbadis.2013.12.009] [Citation(s) in RCA: 170] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Accepted: 12/17/2013] [Indexed: 12/17/2022]
Abstract
The contribution of the nucleolus to cancer is well established with respect to its traditional role in facilitating ribosome biogenesis and proliferative capacity. More contemporary studies however, infer that nucleoli contribute a much broader role in malignant transformation. Specifically, extra-ribosomal functions of the nucleolus position it as a central integrator of cellular proliferation and stress signaling, and are emerging as important mechanisms for modulating how oncogenes and tumor suppressors operate in normal and malignant cells. The dependence of certain tumor cells to co-opt nucleolar processes to maintain their cancer phenotypes has now clearly been demonstrated by the application of small molecule inhibitors of RNA Polymerase I to block ribosomal DNA transcription and disrupt nucleolar function (Bywater et al., 2012 [1]). These drugs, which selectively kill tumor cells in vivo while sparing normal cells, have now progressed to clinical trials. It is likely that we have only just begun to scratch the surface of the potential of the nucleolus as a new target for cancer therapy, with "suppression of nucleolar stress" representing an emerging "hallmark" of cancer. This article is part of a Special Issue entitled: Role of the Nucleolus in Human Disease.
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Affiliation(s)
- Jaclyn E Quin
- Oncogenic Signalling and Growth Control Program, Peter MacCallum Cancer Centre, East Melbourne, Victoria, Australia; Department of Biochemistry and Molecular Biology, The University of Melbourne, Parkville, Victoria, Australia
| | - Jennifer R Devlin
- Oncogenic Signalling and Growth Control Program, Peter MacCallum Cancer Centre, East Melbourne, Victoria, Australia; Department of Biochemistry and Molecular Biology, The University of Melbourne, Parkville, Victoria, Australia
| | - Donald Cameron
- Oncogenic Signalling and Growth Control Program, Peter MacCallum Cancer Centre, East Melbourne, Victoria, Australia
| | - Kate M Hannan
- Oncogenic Signalling and Growth Control Program, Peter MacCallum Cancer Centre, East Melbourne, Victoria, Australia; Department of Biochemistry and Molecular Biology, The University of Melbourne, Parkville, Victoria, Australia
| | - Richard B Pearson
- Oncogenic Signalling and Growth Control Program, Peter MacCallum Cancer Centre, East Melbourne, Victoria, Australia; Department of Biochemistry and Molecular Biology, The University of Melbourne, Parkville, Victoria, Australia; Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, Victoria, Australia; Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Ross D Hannan
- Oncogenic Signalling and Growth Control Program, Peter MacCallum Cancer Centre, East Melbourne, Victoria, Australia; Department of Biochemistry and Molecular Biology, The University of Melbourne, Parkville, Victoria, Australia; Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, Victoria, Australia; Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia; Department of Pathology, The University of Melbourne, Parkville, Victoria, Australia; School of Biomedical Sciences, The University of Queensland, St Lucia, Queensland, Australia.
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Nag S, Chouhan DK, Balaji SN, Chakraborty A, Lhouvum K, Bal C, Sharon A, Trivedi V. Comprehensive screening of heterocyclic compound libraries to identify novel inhibitors for PfRIO-2 kinase through docking and substrate competition studies. Med Chem Res 2013. [DOI: 10.1007/s00044-013-0483-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Jacob MD, Audas TE, Uniacke J, Trinkle-Mulcahy L, Lee S. Environmental cues induce a long noncoding RNA-dependent remodeling of the nucleolus. Mol Biol Cell 2013; 24:2943-53. [PMID: 23904269 PMCID: PMC3771955 DOI: 10.1091/mbc.e13-04-0223] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Environmental signals, such heat shock and acidosis, induce a structural and functional remodeling of the nucleolus. This process, which depends on the expression of intergenic long noncoding RNA, reversibly converts the nucleolus from a transcriptionally active ribosome factory into a transcriptionally inert prison for proteins. The nucleolus is a plurifunctional organelle in which structure and function are intimately linked. Its structural plasticity has long been appreciated, particularly in response to transcriptional inhibition and other cellular stresses, although the mechanism and physiological relevance of these phenomena are unclear. Using MCF-7 and other mammalian cell lines, we describe a structural and functional adaptation of the nucleolus, triggered by heat shock or physiological acidosis, that depends on the expression of ribosomal intergenic spacer long noncoding RNA (IGS lncRNA). At the heart of this process is the de novo formation of a large subnucleolar structure, termed the detention center (DC). The DC is a spatially and dynamically distinct region, characterized by an 8-anilino-1-naphthalenesulfonate–positive hydrophobic signature. Its formation is accompanied by redistribution of nucleolar factors and arrest in ribosomal biogenesis. Silencing of regulatory IGS lncRNA prevents the creation of this structure and allows the nucleolus to retain its tripartite organization and transcriptional activity. Signal termination causes a decrease in IGS transcript levels and a return to the active nucleolar conformation. We propose that the induction of IGS lncRNA by environmental signals operates as a molecular switch that regulates the structure and function of the nucleolus.
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Affiliation(s)
- Mathieu D Jacob
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada
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Sardana R, White JP, Johnson AW. The rRNA methyltransferase Bud23 shows functional interaction with components of the SSU processome and RNase MRP. RNA (NEW YORK, N.Y.) 2013; 19:828-40. [PMID: 23604635 PMCID: PMC3683916 DOI: 10.1261/rna.037671.112] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2012] [Accepted: 03/14/2013] [Indexed: 05/25/2023]
Abstract
Bud23 is responsible for the conserved methylation of G1575 of 18S rRNA, in the P-site of the small subunit of the ribosome. bud23Δ mutants have severely reduced small subunit levels and show a general failure in cleavage at site A2 during rRNA processing. Site A2 is the primary cleavage site for separating the precursors of 18S and 25S rRNAs. Here, we have taken a genetic approach to identify the functional environment of BUD23. We found mutations in UTP2 and UTP14, encoding components of the SSU processome, as spontaneous suppressors of a bud23Δ mutant. The suppressors improved growth and subunit balance and restored cleavage at site A2. In a directed screen of 50 ribosomal trans-acting factors, we identified strong positive and negative genetic interactions with components of the SSU processome and strong negative interactions with components of RNase MRP. RNase MRP is responsible for cleavage at site A3 in pre-rRNA, an alternative cleavage site for separating the precursor rRNAs. The strong negative genetic interaction between RNase MRP mutants and bud23Δ is likely due to the combined defects in cleavage at A2 and A3. Our results suggest that Bud23 plays a role at the time of A2 cleavage, earlier than previously thought. The genetic interaction with the SSU processome suggests that Bud23 could be involved in triggering disassembly of the SSU processome, or of particular subcomplexes of the processome.
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Insights into the mechanism of ribosomal incorporation of mammalian L13a protein during ribosome biogenesis. Mol Cell Biol 2013; 33:2829-42. [PMID: 23689135 DOI: 10.1128/mcb.00250-13] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
In contrast to prokaryotes, the precise mechanism of incorporation of ribosomal proteins into ribosomes in eukaryotes is not well understood. For the majority of eukaryotic ribosomal proteins, residues critical for rRNA binding, a key step in the hierarchical assembly of ribosomes, have not been well defined. In this study, we used the mammalian ribosomal protein L13a as a model to investigate the mechanism(s) underlying eukaryotic ribosomal protein incorporation into ribosomes. This work identified the arginine residue at position 68 of L13a as being essential for L13a binding to rRNA and incorporation into ribosomes. We also demonstrated that incorporation of L13a takes place during maturation of the 90S preribosome in the nucleolus, but that translocation of L13a into the nucleolus is not sufficient for its incorporation into ribosomes. Incorporation of L13a into the 90S preribosome was required for rRNA methylation within the 90S complex. However, mutations abolishing ribosomal incorporation of L13a did not affect its ability to be phosphorylated or its extraribosomal function in GAIT element-mediated translational silencing. These results provide new insights into the mechanism of ribosomal incorporation of L13a and will be useful in guiding future studies aimed at fully deciphering mammalian ribosome biogenesis.
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42
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Proteasome activity influences UV-mediated subnuclear localization changes of NPM. PLoS One 2013; 8:e59096. [PMID: 23554979 PMCID: PMC3595268 DOI: 10.1371/journal.pone.0059096] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2012] [Accepted: 02/12/2013] [Indexed: 01/08/2023] Open
Abstract
UV damage activates cellular stress signaling pathways, causes DNA helix distortions and inhibits transcription by RNA polymerases I and II. In particular, the nucleolus, which is the site of RNA polymerase I transcription and ribosome biogenesis, disintegrates following UV damage. The disintegration is characterized by reorganization of the subnucleolar structures and change of localization of many nucleolar proteins. Here we have queried the basis of localization change of nucleophosmin (NPM), a nucleolar granular component protein, which is increasingly detected in the nucleoplasm following UV radiation. Using photobleaching experiments of NPM-fluorescent fusion protein in live human cells we show that NPM mobility increases after UV damage. However, we show that the increase in NPM nucleoplasmic abundance after UV is independent of UV-activated cellular stress and DNA damage signaling pathways. Unexpectedly, we find that proteasome activity affects NPM redistribution. NPM nucleolar expression was maintained when the UV-treated cells were exposed to proteasome inhibitors or when the expression of proteasome subunits was inhibited using RNAi. However, there was no evidence of increased NPM turnover in the UV damaged cells, or that ubiquitin or ubiquitin recycling affected NPM localization. These findings suggest that proteasome activity couples to nucleolar protein localizations in UV damage stress.
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Abstract
Caveolae are omega-shaped membrane invaginations present in essentially all cell types of the cardiovascular system, including endothelial cells, smooth muscle cells, macrophages, cardiac myocytes, and fibroblasts. Numerous functions have been ascribed to this omega-shaped structure. Caveolae are enriched with different signaling molecules and ion channel regulatory proteins and function both in protein trafficking and signal transduction in these cell types. Caveolins are the structural proteins that are necessary for the formation of caveola membrane domains. Mechanistically, caveolins interact with a variety of downstream signaling molecules, as, for example, Src-family tyrosine kinase, p42/44 mitogen-activated protein (MAP) kinase, and endothelial nitric oxide synthase (eNOS) and hold the signal transducers in the inactive condition until activated with proper stimulus. Caveolae are gradually acquiring increasing attention as cellular organelles contributing to the pathogenesis of several structural and functional processes including cardiac hypertrophy, atherosclerosis, and heart failure. At present, very little is known about the role of caveolae in cardiac function and dysfunction, although recent studies with caveolin knock-out mouse have shown that caveolae and caveolins play a pivotal role in various human pathobiological conditions. This review will discuss the possible role and mechanism of action of caveolae and caveolins in different cardiac diseases.
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Affiliation(s)
- Manika Das
- Cardiovascular Research Center, University of Connecticut School of Medicine, Farmington, CT 06030-1110, USA
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Stępiński D. Nucleolin level in plant root meristematic cells under chilling stress and recovery. Micron 2012; 43:870-5. [PMID: 22483616 DOI: 10.1016/j.micron.2012.02.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2011] [Revised: 02/27/2012] [Accepted: 02/28/2012] [Indexed: 10/28/2022]
Abstract
Nucleolin and its homologues are multifunctional proteins which reside mainly in nucleoli of yeast, animal and plant cells. Hence, they are generally implicated in many stages of ribosome biosynthesis. In this study nucleolin was identified in root meristematic cell nucleoli of soybean plants subjected to chilling stress, recovered after chilling and under control conditions with the use of the immunogold electron microscopy technique. Soybean nucleoli exhibited various metabolic activities under these conditions (Stępiński, 2004). Current studies showed that the level of nucleolin, expressed as a number of gold grains per μm(2), varied in particular subnucleolar regions in the soybean root meristematic cell nucleoli. Labeling density changed in these regions when plants were subjected to the given treatment. Most abundantly this protein was present in dense fibrillar component (DFC) around fibrillar centers (FCs) in the nucleoli of recovered plants, while in the nucleoli of stressed plants this region contained the lowest level of nucleolin. It can be supposed that nucleolin participates in ribosome biogenesis and its level is correlated with metabolic activity of soybean nucleoli - the more active nucleoli, the higher level of nucleolin and vice versa.
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Affiliation(s)
- Dariusz Stępiński
- Department of Cytophysiology, University of Łódź, Pomorska 141/143, 90-236 Łódź, Poland.
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Stępiński D. Immunofluorescent localization of ubiquitin and proteasomes in nucleolar vacuoles of soybean root meristematic cells. Eur J Histochem 2012; 56:e13. [PMID: 22688294 PMCID: PMC3428962 DOI: 10.4081/ejh.2012.13] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2011] [Revised: 01/27/2012] [Accepted: 01/27/2012] [Indexed: 01/01/2023] Open
Abstract
In this study, using the immunofluorescent method, the immunopositive signals to ubiquitin and proteasomes in nucleoli of root meristematic cells of soybean seedlings have been observed. In fact, those signals were present exclusively in nucleolar vacuoles. No signals were observed in the nucleolar territory out of the nucleolar vacuoles or in the nucleoli without vacuoles. The ubiquitin-proteasome system (UPS) may act within the nucleoli of plants with high metabolic activities and may provide an additional level of regulation of intracellular proteolysis via compartment-specific activities of their components. It is suggested that the presence of the UPS solely in vacuolated nucleoli serves as a mechanism that enhances the speed of ribosome subunit production in very actively transcribing nucleoli. On the other hand, nucleolar vacuoles in a cell/nucleus could play additional roles associated with temporary sequestration or storage of some cellular factors, including components of the ubiquitin-proteasome system.
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Affiliation(s)
- D Stępiński
- Department of Cytophysiology, University of Łódź, Poland.
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Boddapati N, Anbarasu K, Suryaraja R, Tendulkar AV, Mahalingam S. Subcellular distribution of the human putative nucleolar GTPase GNL1 is regulated by a novel arginine/lysine-rich domain and a GTP binding domain in a cell cycle-dependent manner. J Mol Biol 2012; 416:346-66. [PMID: 22244851 DOI: 10.1016/j.jmb.2011.12.066] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2011] [Revised: 12/21/2011] [Accepted: 12/30/2011] [Indexed: 12/17/2022]
Abstract
GNL1, a putative nucleolar GTPase, belongs to the MMR1-HSR1 family of large GTPases that are emerging as crucial coordinators of signaling cascades in different cellular compartments. Members of this family share very closely related G-domains, but the signals and pathways regulating their subcellular localization with respect to cell growth remain unknown. To understand the nuclear transport mechanism of GNL1, we have identified a novel arginine/lysine-rich nucleolar localization signal in the NH(2)-terminus that is shown to translocate GNL1 and a heterologous protein to the nucleus/nucleolus in a pathway that is independent of importin-α and importin-β. In addition, the present investigation provided evidence that GNL1 localized to the nucleus and the nucleolus only in G2 stage, in contrast to its cytoplasmic localization in the G1 and S phases of the cell cycle. Using heterokaryon assay, we have demonstrated that GNL1 shuttles between the nucleus and the cytoplasm and that the motif between amino acids 201 and 225 is essential for its export from the nucleus by a signal-mediated CRM1-independent pathway. Alanine-scanning mutagenesis of conserved residues within G-domains suggests that the G2 motif is critical for guanine nucleotide triphosphate (GTP) binding of GNL1 and further showed that nucleolar retention of GNL1 is regulated by a GTP-gating-mediated mechanism. Expression of wild-type GNL1 promotes G2/M transition, in contrast to the G-domain mutant (G2m), which fails to localize to the nucleolus. These data suggest that nucleolar translocation during G2 phase may be critical for faster M-phase transition during cell proliferation. Replacement of conserved residues within the G5 motif alters the stability of GNL1 without changing GTP binding activity. Finally, our data suggest that ongoing transcription is essential for the efficient localization of GNL1 to the nucleolus. Overall, the results reported here demonstrate that multiple mechanisms are involved in the translocation of GNL1 to the nucleolus in a cell cycle-dependent manner to regulate cell growth and proliferation.
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Affiliation(s)
- Neelima Boddapati
- Laboratory of Molecular Virology and Cell Biology, Department of Biotechnology, Indian Institute of Technology-Madras, Chennai 600 036, India
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Caveolae and the regulation of endocytosis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 729:14-28. [PMID: 22411311 DOI: 10.1007/978-1-4614-1222-9_2] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Although clathrin-mediated endocytosis constitutes the main pathway for internalization of extracellular ligands and plasma membrane components it has generally been accepted that other uptake mechanisms-caveolae-mediated and noncaveolar raft-dependent endocytosis-also exist. During the last 20 years many papers have been published about caveolar endocytosis. These studies have fundamentally changed our view about the endocytotic role of caveolae. Views that caveolae are permanently static structures1 have been extensively considered and rejected. Although the initial steps leading to the pinching off of caveolae from the plasma membrane have been studied in details, there are still contradictory data about the intracellular trafficking of caveolae. It is still not entirely clear whether caveolar endocytosis represents an uptake pathway with distinct cellular compartments to avoid lysosomal degradation or ligands taken up by caveolae can also be targeted to late endosomes/lysosomes.In this chapter, we summarize the data available about caveolar endocytosis focusing on the intracellular route of caveolae and we provide data supporting that caveolar endocytosis can join the classical endocytotic pathway.
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Jitsukawa M, Kyogoku H, Ogushi S, Miyano T. Effects of proteasome inhibitors on the nucleolar size of porcine oocytes. J Reprod Dev 2011; 58:162-6. [PMID: 22095088 DOI: 10.1262/jrd.11-134a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
During the final stage of oocyte growth, the morphology of the oocyte nucleoli changes into a compact structure. The objective of this study was to determine the involvement of the proteasome, which is a large protein complex responsible for degrading intracellular proteins, in the nucleolar compaction. The mean nucleolar diameter of growing porcine oocytes (about 100 µm in diameter) was larger than that of fully grown (120 µm) oocytes (15.5 ± 0.3 vs. 13.2 ± 0.1 µm, P<0.05). When fully grown oocytes were treated with proteasome inhibitors, MG132 (10 and 20 µM) and lactacystin (100 and 200 µM), the nucleolar diameter significantly increased from 12.9 µm to 14.9-16.1 µm. In contrast, transcription inhibitors, actinomycin D (0.8-8 µM) and α-amanitin (10-100 µM) reduced the nucleolar diameter of growing oocytes to 9.4-12.4 µm. MG132 partially prevented this reduction in nucleolar diameter. These results suggest that the proteasome regulates the nucleolar size in porcine oocytes perhaps through the degradation of nucleolar proteins.
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Affiliation(s)
- Mayumi Jitsukawa
- Graduate School of Agricultural Science, Kobe University, Kobe 657-8501, Japan
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Johnson JG, Morey JS, Neely MG, Ryan JC, Van Dolah FM. Transcriptome remodeling associated with chronological aging in the dinoflagellate, Karenia brevis. Mar Genomics 2011; 5:15-25. [PMID: 22325718 DOI: 10.1016/j.margen.2011.08.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2011] [Revised: 08/15/2011] [Accepted: 08/19/2011] [Indexed: 10/17/2022]
Abstract
The toxic dinoflagellate, Karenia brevis, forms dense blooms in the Gulf of Mexico that persist for many months in coastal waters, where they can cause extensive marine animal mortalities and human health impacts. The mechanisms that enable cell survival in high density, low growth blooms, and the mechanisms leading to often rapid bloom demise are not well understood. To gain an understanding of processes that underlie chronological aging in this dinoflagellate, a microarray study was carried out to identify changes in the global transcriptome that accompany the entry and maintenance of stationary phase up to the onset of cell death. The transcriptome of K. brevis was assayed using a custom 10,263 feature oligonucleotide microarray from mid-logarithmic growth to the onset of culture demise. A total of 2958 (29%) features were differentially expressed, with the mid-stationary phase timepoint demonstrating peak changes in expression. Gene ontology enrichment analyses identified a significant shift in transcripts involved in energy acquisition, ribosome biogenesis, gene expression, stress adaptation, calcium signaling, and putative brevetoxin biosynthesis. The extensive remodeling of the transcriptome observed in the transition into a quiescent non-dividing phase appears to be indicative of a global shift in the metabolic and signaling requirements and provides the basis from which to understand the process of chronological aging in a dinoflagellate.
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Affiliation(s)
- Jillian G Johnson
- NOAA Center for Coastal Environmental Health and Biomolecular Research, Charleston, SC 29412, USA.
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50
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Moore HM, Bai B, Boisvert FM, Latonen L, Rantanen V, Simpson JC, Pepperkok R, Lamond AI, Laiho M. Quantitative proteomics and dynamic imaging of the nucleolus reveal distinct responses to UV and ionizing radiation. Mol Cell Proteomics 2011; 10:M111.009241. [PMID: 21778410 DOI: 10.1074/mcp.m111.009241] [Citation(s) in RCA: 96] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The nucleolus is a nuclear organelle that coordinates rRNA transcription and ribosome subunit biogenesis. Recent proteomic analyses have shown that the nucleolus contains proteins involved in cell cycle control, DNA processing and DNA damage response and repair, in addition to the many proteins connected with ribosome subunit production. Here we study the dynamics of nucleolar protein responses in cells exposed to stress and DNA damage caused by ionizing and ultraviolet (UV) radiation in diploid human fibroblasts. We show using a combination of imaging and quantitative proteomics methods that nucleolar substructure and the nucleolar proteome undergo selective reorganization in response to UV damage. The proteomic responses to UV include alterations of functional protein complexes such as the SSU processome and exosome, and paraspeckle proteins, involving both decreases and increases in steady state protein ratios, respectively. Several nonhomologous end-joining proteins (NHEJ), such as Ku70/80, display similar fast responses to UV. In contrast, nucleolar proteomic responses to IR are both temporally and spatially distinct from those caused by UV, and more limited in terms of magnitude. With the exception of the NHEJ and paraspeckle proteins, where IR induces rapid and transient changes within 15 min of the damage, IR does not alter the ratios of most other functional nucleolar protein complexes. The rapid transient decrease of NHEJ proteins in the nucleolus indicates that it may reflect a response to DNA damage. Our results underline that the nucleolus is a specific stress response organelle that responds to different damage and stress agents in a unique, damage-specific manner.
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Affiliation(s)
- Henna M Moore
- Molecular Cancer Biology Program and Haartman Institute, University of Helsinki, FIN-00014 Helsinki, Finland
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