1
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Wells CA, Choi J. Transcriptional Profiling of Stem Cells: Moving from Descriptive to Predictive Paradigms. Stem Cell Reports 2020; 13:237-246. [PMID: 31412285 PMCID: PMC6700522 DOI: 10.1016/j.stemcr.2019.07.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 07/09/2019] [Accepted: 07/10/2019] [Indexed: 12/24/2022] Open
Abstract
Transcriptional profiling is a powerful tool commonly used to benchmark stem cells and their differentiated progeny. As the wealth of stem cell data builds in public repositories, we highlight common data traps, and review approaches to combine and mine this data for new cell classification and cell prediction tools. We touch on future trends for stem cell profiling, such as single-cell profiling, long-read sequencing, and improved methods for measuring molecular modifications on chromatin and RNA that bring new challenges and opportunities for stem cell analysis.
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Affiliation(s)
- Christine A Wells
- Centre for Stem Cell Systems, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville 3010, Australia.
| | - Jarny Choi
- Centre for Stem Cell Systems, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville 3010, Australia
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2
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Pereira IT, Spangenberg L, Robert AW, Amorín R, Stimamiglio MA, Naya H, Dallagiovanna B. Cardiomyogenic differentiation is fine-tuned by differential mRNA association with polysomes. BMC Genomics 2019; 20:219. [PMID: 30876407 PMCID: PMC6420765 DOI: 10.1186/s12864-019-5550-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 02/20/2019] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Cardiac cell fate specification occurs through progressive steps, and its gene expression regulation features are still being defined. There has been an increasing interest in understanding the coordination between transcription and post-transcriptional regulation during the differentiation processes. Here, we took advantage of the polysome profiling technique to isolate and high-throughput sequence ribosome-free and polysome-bound RNAs during cardiomyogenesis. RESULTS We showed that polysome-bound RNAs exhibit the cardiomyogenic commitment gene expression and that mesoderm-to-cardiac progenitor stages are strongly regulated. Additionally, we compared ribosome-free and polysome-bound RNAs and found that the post-transcriptional regulation vastly contributes to cardiac phenotype determination, including RNA recruitment to and dissociation from ribosomes. Moreover, we found that protein synthesis is decreased in cardiomyocytes compared to human embryonic stem-cells (hESCs), possibly due to the down-regulation of translation-related genes. CONCLUSIONS Our data provided a powerful tool to investigate genes potentially controlled by post-transcriptional mechanisms during the cardiac differentiation of hESC. This work could prospect fundamental tools to develop new therapy and research approaches.
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Affiliation(s)
- Isabela Tiemy Pereira
- Basic Stem-cell Biology Laboratory, Instituto Carlos Chagas - FIOCRUZ-PR, Rua Professor Algacyr Munhoz Mader, 3775, Curitiba, PR, 81.350-010, Brazil
| | - Lucia Spangenberg
- Bioinformatics Unit, Institut Pasteur de Montevideo, Mataojo 2020, 11400, Montevideo, Uruguay
| | - Anny Waloski Robert
- Basic Stem-cell Biology Laboratory, Instituto Carlos Chagas - FIOCRUZ-PR, Rua Professor Algacyr Munhoz Mader, 3775, Curitiba, PR, 81.350-010, Brazil
| | - Rocío Amorín
- Bioinformatics Unit, Institut Pasteur de Montevideo, Mataojo 2020, 11400, Montevideo, Uruguay
| | - Marco Augusto Stimamiglio
- Basic Stem-cell Biology Laboratory, Instituto Carlos Chagas - FIOCRUZ-PR, Rua Professor Algacyr Munhoz Mader, 3775, Curitiba, PR, 81.350-010, Brazil
| | - Hugo Naya
- Bioinformatics Unit, Institut Pasteur de Montevideo, Mataojo 2020, 11400, Montevideo, Uruguay
| | - Bruno Dallagiovanna
- Basic Stem-cell Biology Laboratory, Instituto Carlos Chagas - FIOCRUZ-PR, Rua Professor Algacyr Munhoz Mader, 3775, Curitiba, PR, 81.350-010, Brazil.
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3
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Polysome profiling followed by RNA-seq of cardiac differentiation stages in hESCs. Sci Data 2018; 5:180287. [PMID: 30512016 PMCID: PMC6278691 DOI: 10.1038/sdata.2018.287] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Accepted: 10/23/2018] [Indexed: 12/12/2022] Open
Abstract
The regulation of gene expression acts at numerous complementary levels to control and refine protein abundance. The analysis of mRNAs associated with polysomes, called polysome profiling, has been used to investigate the post-transcriptional mechanisms that are involved in different biological processes. Pluripotent stem cells are able to differentiate into a variety of cell lineages, and the cell commitment progression is carefully orchestrated. Genome-wide expression profiling has provided the possibility to investigate transcriptional changes during cardiomyogenesis; however, a more accurate study regarding post-transcriptional regulation is required. In the present work, we isolated and high-throughput sequenced ribosome-free and polysome-bound RNAs from NKX2-5eGFP/w HES3 undifferentiated pluripotent stem cells at the subsequent differentiation stages of cardiomyogenesis: embryoid body aggregation, mesoderm, cardiac progenitor and cardiomyocyte. The expression of developmental markers was followed by flow cytometry, and quality analyses were performed as technical controls to ensure high quality data. Our dataset provides valuable information about hESC cardiac differentiation and can be used to investigate genes potentially controlled by post-transcriptional mechanisms.
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4
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Marcon BH, Holetz FB, Eastman G, Origa-Alves AC, Amorós MA, de Aguiar AM, Rebelatto CK, Brofman PRS, Sotelo-Silveira J, Dallagiovanna B. Downregulation of the protein synthesis machinery is a major regulatory event during early adipogenic differentiation of human adipose-derived stromal cells. Stem Cell Res 2017; 25:191-201. [PMID: 29156375 DOI: 10.1016/j.scr.2017.10.027] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Revised: 10/11/2017] [Accepted: 10/27/2017] [Indexed: 12/26/2022] Open
Abstract
Commitment of adult stem cells involves the activation of specific gene networks regulated from transcription to protein synthesis. Here, we used ribosome profiling to identify mRNAs regulated at the translational level, through both differential association to polysomes and modulation of their translational rates. We observed that translational regulation during the differentiation of human adipose-derived stromal cells (hASCs, also known as adipose-derived mesenchymal stem cells), a subset of which are stem cells, to adipocytes was a major regulatory event. hASCs showed a significant reduction of whole protein synthesis after adipogenic induction and a downregulation of the expression and translational efficiency of ribosomal proteins. Additionally, focal adhesion and cytoskeletal proteins were downregulated at the translational level. This negative regulation of the essential biological functions of hASCs resulted in a reduction in cell size and the potential of hASCs to migrate. We analyzed whether the inactivation of key translation initiation factors was involved in this observed major repression of translation. We showed that there was an increase in the hypo phosphorylated forms of 4E-BP1, a negative regulator of translation, during early adipogenesis. Our results showed that extensive translational regulation occurred during the early stage of the adipogenic differentiation of hASCs.
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Affiliation(s)
- Bruna H Marcon
- Instituto Carlos Chagas, Fiocruz-Paraná, Rua Professor Algacyr Munhoz Mader, 3775, Curitiba, PR 81350-010, Brazil
| | - Fabíola B Holetz
- Instituto Carlos Chagas, Fiocruz-Paraná, Rua Professor Algacyr Munhoz Mader, 3775, Curitiba, PR 81350-010, Brazil
| | - Guillermo Eastman
- Department of Genomics, Instituto de Investigaciones Biológicas Clemente Estable, Avenida Italia 3318, CP 11600 Montevideo, Uruguay
| | - Ana Carolina Origa-Alves
- Instituto Carlos Chagas, Fiocruz-Paraná, Rua Professor Algacyr Munhoz Mader, 3775, Curitiba, PR 81350-010, Brazil
| | - Mariana Andrea Amorós
- Laboratory of Stem Cells, Institute of Biology and Experimental Medicine - National Council of Scientific and Technical Research (IByME-CONICET), Ciudad Autónoma de Buenos Aires, Argentina
| | - Alessandra Melo de Aguiar
- Instituto Carlos Chagas, Fiocruz-Paraná, Rua Professor Algacyr Munhoz Mader, 3775, Curitiba, PR 81350-010, Brazil
| | - Carmen K Rebelatto
- Núcleo de Tecnologia Celular, Pontifícia Universidade Católica do Paraná, Rua Imaculada Conceição, 1155, Curitiba, PR 80215-901, Brazil
| | - Paulo R S Brofman
- Núcleo de Tecnologia Celular, Pontifícia Universidade Católica do Paraná, Rua Imaculada Conceição, 1155, Curitiba, PR 80215-901, Brazil
| | - Jose Sotelo-Silveira
- Department of Genomics, Instituto de Investigaciones Biológicas Clemente Estable, Avenida Italia 3318, CP 11600 Montevideo, Uruguay; Department of Cell and Molecular Biology, School of Sciences, Universidad de la República, Montevideo, Uruguay.
| | - Bruno Dallagiovanna
- Instituto Carlos Chagas, Fiocruz-Paraná, Rua Professor Algacyr Munhoz Mader, 3775, Curitiba, PR 81350-010, Brazil.
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5
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Han H, Braunschweig U, Gonatopoulos-Pournatzis T, Weatheritt RJ, Hirsch CL, Ha KCH, Radovani E, Nabeel-Shah S, Sterne-Weiler T, Wang J, O'Hanlon D, Pan Q, Ray D, Zheng H, Vizeacoumar F, Datti A, Magomedova L, Cummins CL, Hughes TR, Greenblatt JF, Wrana JL, Moffat J, Blencowe BJ. Multilayered Control of Alternative Splicing Regulatory Networks by Transcription Factors. Mol Cell 2017; 65:539-553.e7. [PMID: 28157508 DOI: 10.1016/j.molcel.2017.01.011] [Citation(s) in RCA: 100] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Revised: 11/16/2016] [Accepted: 01/05/2017] [Indexed: 12/21/2022]
Abstract
Networks of coordinated alternative splicing (AS) events play critical roles in development and disease. However, a comprehensive knowledge of the factors that regulate these networks is lacking. We describe a high-throughput system for systematically linking trans-acting factors to endogenous RNA regulatory events. Using this system, we identify hundreds of factors associated with diverse regulatory layers that positively or negatively control AS events linked to cell fate. Remarkably, more than one-third of the regulators are transcription factors. Further analyses of the zinc finger protein Zfp871 and BTB/POZ domain transcription factor Nacc1, which regulate neural and stem cell AS programs, respectively, reveal roles in controlling the expression of specific splicing regulators. Surprisingly, these proteins also appear to regulate target AS programs via binding RNA. Our results thus uncover a large "missing cache" of splicing regulators among annotated transcription factors, some of which dually regulate AS through direct and indirect mechanisms.
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Affiliation(s)
- Hong Han
- Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | | | | | - Robert J Weatheritt
- Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada; MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Calley L Hirsch
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, ON M5G 1X5, Canada
| | - Kevin C H Ha
- Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Ernest Radovani
- Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Syed Nabeel-Shah
- Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | | | - Juli Wang
- Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada
| | - Dave O'Hanlon
- Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada
| | - Qun Pan
- Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada
| | - Debashish Ray
- Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada
| | - Hong Zheng
- Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada
| | - Frederick Vizeacoumar
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, ON M5G 1X5, Canada
| | - Alessandro Datti
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, ON M5G 1X5, Canada
| | - Lilia Magomedova
- Department of Pharmaceutical Sciences, University of Toronto, Toronto, ON M5S 3M2, Canada
| | - Carolyn L Cummins
- Department of Pharmaceutical Sciences, University of Toronto, Toronto, ON M5S 3M2, Canada
| | - Timothy R Hughes
- Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Jack F Greenblatt
- Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Jeffrey L Wrana
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada; Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, ON M5G 1X5, Canada
| | - Jason Moffat
- Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Benjamin J Blencowe
- Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada.
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6
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O'Brien CM, Chy HS, Zhou Q, Blumenfeld S, Lambshead JW, Liu X, Kie J, Capaldo BD, Chung TL, Adams TE, Phan T, Bentley JD, McKinstry WJ, Oliva K, McMurrick PJ, Wang YC, Rossello FJ, Lindeman GJ, Chen D, Jarde T, Clark AT, Abud HE, Visvader JE, Nefzger CM, Polo JM, Loring JF, Laslett AL. New Monoclonal Antibodies to Defined Cell Surface Proteins on Human Pluripotent Stem Cells. Stem Cells 2017; 35:626-640. [PMID: 28009074 PMCID: PMC5412944 DOI: 10.1002/stem.2558] [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: 05/31/2016] [Revised: 10/31/2016] [Accepted: 11/18/2016] [Indexed: 01/28/2023]
Abstract
The study and application of human pluripotent stem cells (hPSCs) will be enhanced by the availability of well‐characterized monoclonal antibodies (mAbs) detecting cell‐surface epitopes. Here, we report generation of seven new mAbs that detect cell surface proteins present on live and fixed human ES cells (hESCs) and human iPS cells (hiPSCs), confirming our previous prediction that these proteins were present on the cell surface of hPSCs. The mAbs all show a high correlation with POU5F1 (OCT4) expression and other hPSC surface markers (TRA‐160 and SSEA‐4) in hPSC cultures and detect rare OCT4 positive cells in differentiated cell cultures. These mAbs are immunoreactive to cell surface protein epitopes on both primed and naive state hPSCs, providing useful research tools to investigate the cellular mechanisms underlying human pluripotency and states of cellular reprogramming. In addition, we report that subsets of the seven new mAbs are also immunoreactive to human bone marrow‐derived mesenchymal stem cells (MSCs), normal human breast subsets and both normal and tumorigenic colorectal cell populations. The mAbs reported here should accelerate the investigation of the nature of pluripotency, and enable development of robust cell separation and tracing technologies to enrich or deplete for hPSCs and other human stem and somatic cell types. Stem Cells2017;35:626–640
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Affiliation(s)
- Carmel M O'Brien
- Clayton and Parkville, CSIRO Manufacturing, Victoria, Australia.,Australian Regenerative Medicine Institute, Monash University, Clayton, Victoria, Australia
| | - Hun S Chy
- Clayton and Parkville, CSIRO Manufacturing, Victoria, Australia.,Australian Regenerative Medicine Institute, Monash University, Clayton, Victoria, Australia
| | - Qi Zhou
- Clayton and Parkville, CSIRO Manufacturing, Victoria, Australia.,Australian Regenerative Medicine Institute, Monash University, Clayton, Victoria, Australia
| | | | - Jack W Lambshead
- Clayton and Parkville, CSIRO Manufacturing, Victoria, Australia.,Australian Regenerative Medicine Institute, Monash University, Clayton, Victoria, Australia
| | - Xiaodong Liu
- Australian Regenerative Medicine Institute, Monash University, Clayton, Victoria, Australia.,Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia
| | - Joshua Kie
- Clayton and Parkville, CSIRO Manufacturing, Victoria, Australia.,Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia
| | - Bianca D Capaldo
- The Walter and Eliza Hall Institute (WEHI), Parkville, Victoria, Australia.,Department of Medical Biology
| | - Tung-Liang Chung
- Clayton and Parkville, CSIRO Manufacturing, Victoria, Australia.,Australian Regenerative Medicine Institute, Monash University, Clayton, Victoria, Australia
| | - Timothy E Adams
- Clayton and Parkville, CSIRO Manufacturing, Victoria, Australia
| | - Tram Phan
- Clayton and Parkville, CSIRO Manufacturing, Victoria, Australia
| | - John D Bentley
- Clayton and Parkville, CSIRO Manufacturing, Victoria, Australia
| | | | - Karen Oliva
- Department of Surgery, Cabrini Monash University, Malvern, Victoria, Australia
| | - Paul J McMurrick
- Department of Surgery, Cabrini Monash University, Malvern, Victoria, Australia
| | - Yu-Chieh Wang
- Department of Chemical Physiology.,Center for Regenerative Medicine, The Scripps Research Institute, La Jolla, California, USA
| | - Fernando J Rossello
- Australian Regenerative Medicine Institute, Monash University, Clayton, Victoria, Australia.,Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia
| | - Geoffrey J Lindeman
- The Walter and Eliza Hall Institute (WEHI), Parkville, Victoria, Australia.,Department of Medicine, The University of Melbourne, Parkville, Victoria, Australia.,Department of Medical Oncology, The Royal Melbourne Hospital, Parkville, Victoria, Australia
| | - Di Chen
- Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles, California, USA
| | - Thierry Jarde
- Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia.,Cancer Program, Monash Biomedicine Discovery Institute.,Centre for Cancer Research, Hudson Institute of Medical Research, Clayton, Victoria, Australia
| | - Amander T Clark
- Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles, California, USA
| | - Helen E Abud
- Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia.,Cancer Program, Monash Biomedicine Discovery Institute
| | - Jane E Visvader
- The Walter and Eliza Hall Institute (WEHI), Parkville, Victoria, Australia.,Department of Medical Biology
| | - Christian M Nefzger
- Australian Regenerative Medicine Institute, Monash University, Clayton, Victoria, Australia.,Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia
| | - Jose M Polo
- Australian Regenerative Medicine Institute, Monash University, Clayton, Victoria, Australia.,Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia
| | - Jeanne F Loring
- Department of Chemical Physiology.,Center for Regenerative Medicine, The Scripps Research Institute, La Jolla, California, USA
| | - Andrew L Laslett
- Clayton and Parkville, CSIRO Manufacturing, Victoria, Australia.,Australian Regenerative Medicine Institute, Monash University, Clayton, Victoria, Australia
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7
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Seeing is Believing: Tracking Translation Dynamics In Vivo. Trends Biochem Sci 2016; 41:818-821. [DOI: 10.1016/j.tibs.2016.07.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Revised: 07/22/2016] [Accepted: 07/27/2016] [Indexed: 11/21/2022]
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8
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Shaw PJ, Kaewprommal P, Piriyapongsa J, Wongsombat C, Yuthavong Y, Kamchonwongpaisan S. Estimating mRNA lengths from Plasmodium falciparum genes by Virtual Northern RNA-seq analysis. Int J Parasitol 2015; 46:7-12. [PMID: 26548960 DOI: 10.1016/j.ijpara.2015.09.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Revised: 08/21/2015] [Accepted: 09/28/2015] [Indexed: 11/16/2022]
Abstract
Accurate gene models are essential for understanding parasite biology. However, transcript structure information is lacking for most parasite genes. Here, we describe "Virtual Northern" analysis of the malaria parasite Plasmodium falciparum to address this issue. RNA-seq libraries were made from size-fractionated RNA. Transcript sizes for 3052 genes were inferred from the read counts in each library. The data show that for almost half of the transcripts, the combined untranslated regions are more than twice the length of the open reading frame. Furthermore, we identified novel polycistronic, or gene overlapping, transcripts that suggest revisions to current gene models are needed.
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Affiliation(s)
- Philip J Shaw
- Protein-Ligand Engineering and Molecular Biology Laboratory, Medical Molecular Biology Research Unit, National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency (NSTDA), 113 Thailand Science Park, Thanon Phahonyothin, Tambon Khlong Neung, Amphoe Khlong Luang, Pathum Thani 12120, Thailand.
| | - Pavita Kaewprommal
- Biostatistics and Bioinformatics Laboratory, Genome Technology Research Unit, National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency (NSTDA), 113 Thailand Science Park, Thanon Phahonyothin, Tambon Khlong Neung, Amphoe Khlong Luang, Pathum Thani 12120, Thailand
| | - Jittima Piriyapongsa
- Biostatistics and Bioinformatics Laboratory, Genome Technology Research Unit, National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency (NSTDA), 113 Thailand Science Park, Thanon Phahonyothin, Tambon Khlong Neung, Amphoe Khlong Luang, Pathum Thani 12120, Thailand
| | - Chayaphat Wongsombat
- Protein-Ligand Engineering and Molecular Biology Laboratory, Medical Molecular Biology Research Unit, National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency (NSTDA), 113 Thailand Science Park, Thanon Phahonyothin, Tambon Khlong Neung, Amphoe Khlong Luang, Pathum Thani 12120, Thailand
| | - Yongyuth Yuthavong
- Protein-Ligand Engineering and Molecular Biology Laboratory, Medical Molecular Biology Research Unit, National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency (NSTDA), 113 Thailand Science Park, Thanon Phahonyothin, Tambon Khlong Neung, Amphoe Khlong Luang, Pathum Thani 12120, Thailand
| | - Sumalee Kamchonwongpaisan
- Protein-Ligand Engineering and Molecular Biology Laboratory, Medical Molecular Biology Research Unit, National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency (NSTDA), 113 Thailand Science Park, Thanon Phahonyothin, Tambon Khlong Neung, Amphoe Khlong Luang, Pathum Thani 12120, Thailand
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9
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Park SM, Gönen M, Vu L, Minuesa G, Tivnan P, Barlowe TS, Taggart J, Lu Y, Deering RP, Hacohen N, Figueroa ME, Paietta E, Fernandez HF, Tallman MS, Melnick A, Levine R, Leslie C, Lengner CJ, Kharas MG. Musashi2 sustains the mixed-lineage leukemia-driven stem cell regulatory program. J Clin Invest 2015; 125:1286-98. [PMID: 25664853 DOI: 10.1172/jci78440] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Accepted: 01/05/2015] [Indexed: 01/15/2023] Open
Abstract
Leukemia stem cells (LSCs) are found in most aggressive myeloid diseases and contribute to therapeutic resistance. Leukemia cells exhibit a dysregulated developmental program as the result of genetic and epigenetic alterations. Overexpression of the RNA-binding protein Musashi2 (MSI2) has been previously shown to predict poor survival in leukemia. Here, we demonstrated that conditional deletion of Msi2 in the hematopoietic compartment results in delayed leukemogenesis, reduced disease burden, and a loss of LSC function in a murine leukemia model. Gene expression profiling of these Msi2-deficient animals revealed a loss of the hematopoietic/leukemic stem cell self-renewal program and an increase in the differentiation program. In acute myeloid leukemia patients, the presence of a gene signature that was similar to that observed in Msi2-deficent murine LSCs correlated with improved survival. We determined that MSI2 directly maintains the mixed-lineage leukemia (MLL) self-renewal program by interacting with and retaining efficient translation of Hoxa9, Myc, and Ikzf2 mRNAs. Moreover, depletion of MLL target Ikzf2 in LSCs reduced colony formation, decreased proliferation, and increased apoptosis. Our data provide evidence that MSI2 controls efficient translation of the oncogenic LSC self-renewal program and suggest MSI2 as a potential therapeutic target for myeloid leukemia.
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10
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Miura P, Sanfilippo P, Shenker S, Lai EC. Alternative polyadenylation in the nervous system: to what lengths will 3' UTR extensions take us? Bioessays 2014; 36:766-77. [PMID: 24903459 PMCID: PMC4503322 DOI: 10.1002/bies.201300174] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Alternative cleavage and polyadenylation (APA) can diversify coding and non-coding regions, but has particular impact on increasing 3' UTR diversity. Through the gain or loss of regulatory elements such as RNA binding protein and microRNA sites, APA can influence transcript stability, localization, and translational efficiency. Strikingly, the central nervous systems of invertebrate and vertebrate species express a broad range of transcript isoforms bearing extended 3' UTRs. The molecular mechanism that permits proximal 3' end bypass in neurons is mysterious, and only beginning to be elucidated. This landscape of neural 3' UTR extensions, many reaching unprecedented lengths, may help service the unique post-transcriptional regulatory needs of neurons. A combination of approaches, including transcriptome-wide profiling, genetic screening to identify APA factors, biochemical dissection of alternative 3' end formation, and manipulation of individual neural APA targets, will be necessary to gain fuller perspectives on the mechanism and biology of neural-specific 3' UTR lengthening.
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Affiliation(s)
- Pedro Miura
- Department of Developmental Biology, Sloan-Kettering Institute, 1275 York Ave, Box 252, New York NY 10065
| | - Piero Sanfilippo
- Department of Developmental Biology, Sloan-Kettering Institute, 1275 York Ave, Box 252, New York NY 10065
- Louis V. Gerstner, Jr. Graduate School of Biomedical Sciences, Memorial Sloan Kettering Cancer Center
| | - Sol Shenker
- Department of Developmental Biology, Sloan-Kettering Institute, 1275 York Ave, Box 252, New York NY 10065
- Tri-Institutional Program in Computational Biology and Medicine, Weill Cornell Medical College
| | - Eric C. Lai
- Department of Developmental Biology, Sloan-Kettering Institute, 1275 York Ave, Box 252, New York NY 10065
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11
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Mason EA, Mar JC, Laslett AL, Pera MF, Quackenbush J, Wolvetang E, Wells CA. Gene expression variability as a unifying element of the pluripotency network. Stem Cell Reports 2014; 3:365-77. [PMID: 25254348 PMCID: PMC4175554 DOI: 10.1016/j.stemcr.2014.06.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Revised: 06/18/2014] [Accepted: 06/20/2014] [Indexed: 12/16/2022] Open
Abstract
Heterogeneity is a hallmark of stem cell populations, in part due to the molecular differences between cells undergoing self-renewal and those poised to differentiate. We examined phenotypic and molecular heterogeneity in pluripotent stem cell populations, using public gene expression data sets. A high degree of concordance was observed between global gene expression variability and the reported heterogeneity of different human pluripotent lines. Network analysis demonstrated that low-variability genes were the most highly connected, suggesting that these are the most stable elements of the gene regulatory network and are under the highest regulatory constraints. Known drivers of pluripotency were among these, with lowest expression variability of POU5F1 in cells with the highest capacity for self-renewal. Variability of gene expression provides a reliable measure of phenotypic and molecular heterogeneity and predicts those genes with the highest degree of regulatory constraint within the pluripotency network. Gene expression variability is highly concordant with population heterogeneity Genes within the pluripotency network have distinct variability profiles Expression variability is a network property important for pluripotency
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Affiliation(s)
- Elizabeth A Mason
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St. Lucia, Brisbane QSLD 4072, Australia
| | - Jessica C Mar
- The Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Andrew L Laslett
- Materials Science and Engineering, CSIRO, Clayton VIC 3168, Australia
| | - Martin F Pera
- The University of Melbourne, Florey Neuroscience and Mental Health Institute, and Walter and Eliza Hall Institute of Medical Research, Parkville VIC 3010, Australia
| | - John Quackenbush
- Dana-Farber Cancer Institute, Harvard University, Boston, MA 02215 USA
| | - Ernst Wolvetang
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St. Lucia, Brisbane QSLD 4072, Australia
| | - Christine A Wells
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St. Lucia, Brisbane QSLD 4072, Australia; Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8TA, UK.
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12
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Pieters T, van Roy F. Role of cell–cell adhesion complexes in embryonic stem cell biology. J Cell Sci 2014; 127:2603-13. [DOI: 10.1242/jcs.146720] [Citation(s) in RCA: 103] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
ABSTRACT
Pluripotent embryonic stem cells (ESCs) can self-renew or differentiate into any cell type within an organism. Here, we focus on the roles of cadherins and catenins – their cytoplasmic scaffold proteins – in the fate, maintenance and differentiation of mammalian ESCs. E-cadherin is a master stem cell regulator that is required for both mouse ESC (mESC) maintenance and differentiation. E-cadherin interacts with key components of the naive stemness pathway and ablating it prevents stem cells from forming well-differentiated teratomas or contributing to chimeric animals. In addition, depleting E-cadherin converts naive mouse ESCs into primed epiblast-like stem cells (EpiSCs). In line with this, a mesenchymal-to-epithelial transition (MET) occurs during reprogramming of somatic cells towards induced pluripotent stem cells (iPSCs), leading to downregulation of N-cadherin and acquisition of high E-cadherin levels. β-catenin exerts a dual function; it acts in cadherin-based adhesion and in WNT signaling and, although WNT signaling is important for stemness, the adhesive function of β-catenin might be crucial for maintaining the naive state of stem cells. In addition, evidence is rising that other junctional proteins are also important in ESC biology. Thus, precisely regulated levels and activities of several junctional proteins, in particular E-cadherin, safeguard naive pluripotency and are a prerequisite for complete somatic cell reprogramming.
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Affiliation(s)
- Tim Pieters
- Department of Biomedical Molecular Biology, Ghent University, B-9052 Ghent, Belgium
- Molecular and Cellular Oncology Unit, Inflammation Research Center, VIB, B-9052 Ghent, Belgium
| | - Frans van Roy
- Department of Biomedical Molecular Biology, Ghent University, B-9052 Ghent, Belgium
- Molecular Cell Biology Unit, Inflammation Research Center, VIB, B-9052 Ghent, Belgium
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13
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Deep transcriptome profiling of mammalian stem cells supports a regulatory role for retrotransposons in pluripotency maintenance. Nat Genet 2014; 46:558-66. [PMID: 24777452 DOI: 10.1038/ng.2965] [Citation(s) in RCA: 208] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2013] [Accepted: 04/02/2014] [Indexed: 12/12/2022]
Abstract
The importance of microRNAs and long noncoding RNAs in the regulation of pluripotency has been documented; however, the noncoding components of stem cell gene networks remain largely unknown. Here we investigate the role of noncoding RNAs in the pluripotent state, with particular emphasis on nuclear and retrotransposon-derived transcripts. We have performed deep profiling of the nuclear and cytoplasmic transcriptomes of human and mouse stem cells, identifying a class of previously undetected stem cell-specific transcripts. We show that long terminal repeat (LTR)-derived transcripts contribute extensively to the complexity of the stem cell nuclear transcriptome. Some LTR-derived transcripts are associated with enhancer regions and are likely to be involved in the maintenance of pluripotency.
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14
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Aviner R, Geiger T, Elroy-Stein O. PUNCH-P for global translatome profiling: Methodology, insights and comparison to other techniques. ACTA ACUST UNITED AC 2013; 1:e27516. [PMID: 26824027 PMCID: PMC4718054 DOI: 10.4161/trla.27516] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Revised: 12/08/2013] [Accepted: 12/12/2013] [Indexed: 01/14/2023]
Abstract
Regulation of mRNA translation is a major modulator of gene expression, allowing cells to fine tune protein levels during growth and differentiation and in response to physiological signals and environmental changes. Mass-spectrometry and RNA-sequencing methods now enable global profiling of the translatome, but these still involve significant analytical and economical limitations. We developed a novel system-wide proteomic approach for direct monitoring of translation, termed PUromycin-associated Nascent CHain Proteomics (PUNCH-P), which is based on the recovery of ribosome-nascent chain complexes from cells or tissues followed by incorporation of biotinylated puromycin into newly-synthesized proteins. Biotinylated proteins are then purified by streptavidin and analyzed by mass-spectrometry. Here we present an overview of PUNCH-P, describe other methodologies for global translatome profiling (pSILAC, BONCAT, TRAP/Ribo-tag, Ribo-seq) and provide conceptual comparisons between these methods. We also show how PUNCH-P data can be combined with mRNA measurements to determine relative translation efficiency for specific mRNAs.
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Affiliation(s)
- Ranen Aviner
- Department of Cell Research and Immunology; George S. Wise Faculty of Life Sciences; Tel Aviv University; Tel Aviv, Israel
| | - Tamar Geiger
- Department of Human Molecular Genetics and Biochemistry; Sackler Faculty of Medicine; Tel Aviv University, Tel Aviv, Israel
| | - Orna Elroy-Stein
- Department of Cell Research and Immunology; George S. Wise Faculty of Life Sciences; Tel Aviv University; Tel Aviv, Israel
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15
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Spangenberg L, Correa A, Dallagiovanna B, Naya H. Role of alternative polyadenylation during adipogenic differentiation: an in silico approach. PLoS One 2013; 8:e75578. [PMID: 24143171 PMCID: PMC3797115 DOI: 10.1371/journal.pone.0075578] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Accepted: 08/14/2013] [Indexed: 01/22/2023] Open
Abstract
Post-transcriptional regulation of stem cell differentiation is far from being completely understood. Changes in protein levels are not fully correlated with corresponding changes in mRNAs; the observed differences might be partially explained by post-transcriptional regulation mechanisms, such as alternative polyadenylation. This would involve changes in protein binding, transcript usage, miRNAs and other non-coding RNAs. In the present work we analyzed the distribution of alternative transcripts during adipogenic differentiation and the potential role of miRNAs in post-transcriptional regulation. Our in silico analysis suggests a modest, consistent, bias in 3'UTR lengths during differentiation enabling a fine-tuned transcript regulation via small non-coding RNAs. Including these effects in the analyses partially accounts for the observed discrepancies in relative abundance of protein and mRNA.
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Affiliation(s)
- Lucía Spangenberg
- Bioinformatics Unit, Institut Pasteur Montevideo, Montevideo, Uruguay
| | - Alejandro Correa
- Instituto Carlos Chagas, Fiocruz-Paraná, Curitiba, Paraná, Brazil
| | | | - Hugo Naya
- Bioinformatics Unit, Institut Pasteur Montevideo, Montevideo, Uruguay
- Departamento de Producción Animal y Pasturas, Facultad de Agronomía, Universidad de la República
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16
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Yang Y, Wang H, Chang KH, Qu H, Zhang Z, Xiong Q, Qi H, Cui P, Lin Q, Ruan X, Yang Y, Li Y, Shu C, Li Q, Wakeland EK, Yan J, Hu S, Fang X. Transcriptome dynamics during human erythroid differentiation and development. Genomics 2013; 102:431-441. [PMID: 24121002 DOI: 10.1016/j.ygeno.2013.09.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Revised: 09/22/2013] [Accepted: 09/30/2013] [Indexed: 10/26/2022]
Abstract
To explore the mechanisms controlling erythroid differentiation and development, we analyzed the genome-wide transcription dynamics occurring during the differentiation of human embryonic stem cells (HESCs) into the erythroid lineage and development of embryonic to adult erythropoiesis using high throughput sequencing technology. HESCs and erythroid cells at three developmental stages: ESER (embryonic), FLER (fetal), and PBER (adult) were analyzed. Our findings revealed that the number of expressed genes decreased during differentiation, whereas the total expression intensity increased. At each of the three transitions (HESCs-ESERs, ESERs-FLERs, and FLERs-PBERs), many differentially expressed genes were observed, which were involved in maintaining pluripotency, early erythroid specification, rapid cell growth, and cell-cell adhesion and interaction. We also discovered dynamic networks and their central nodes in each transition. Our study provides a fundamental basis for further investigation of erythroid differentiation and development, and has implications in using ESERs for transfusion product in clinical settings.
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Affiliation(s)
- Yadong Yang
- Laboratory of Disease Genomics and Individualized Medicine, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China
| | - Hai Wang
- Laboratory of Disease Genomics and Individualized Medicine, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China
| | - Kai-Hsin Chang
- Division of Hematology, Department of Medicine, University of Washington, Seattle, WA 98195, USA
| | - Hongzhu Qu
- Laboratory of Disease Genomics and Individualized Medicine, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China
| | - Zhaojun Zhang
- Laboratory of Disease Genomics and Individualized Medicine, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China
| | - Qian Xiong
- Laboratory of Disease Genomics and Individualized Medicine, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China
| | - Heyuan Qi
- Laboratory of Disease Genomics and Individualized Medicine, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China
| | - Peng Cui
- CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China
| | - Qiang Lin
- CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China
| | - Xiuyan Ruan
- Laboratory of Disease Genomics and Individualized Medicine, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China
| | - Yaran Yang
- Laboratory of Disease Genomics and Individualized Medicine, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China
| | - Yajuan Li
- Laboratory of Disease Genomics and Individualized Medicine, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China
| | - Chang Shu
- CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China
| | - Quanzhen Li
- Department of Immunology & Microarray Core Facility, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Edward K Wakeland
- Laboratory of Disease Genomics and Individualized Medicine, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China.,Department of Immunology & Microarray Core Facility, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Jiangwei Yan
- Laboratory of Disease Genomics and Individualized Medicine, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China
| | - Songnian Hu
- CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China
| | - Xiangdong Fang
- Laboratory of Disease Genomics and Individualized Medicine, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China
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17
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Spangenberg L, Shigunov P, Abud APR, Cofré AR, Stimamiglio MA, Kuligovski C, Zych J, Schittini AV, Costa ADT, Rebelatto CK, Brofman PRS, Goldenberg S, Correa A, Naya H, Dallagiovanna B. Polysome profiling shows extensive posttranscriptional regulation during human adipocyte stem cell differentiation into adipocytes. Stem Cell Res 2013; 11:902-12. [PMID: 23845413 DOI: 10.1016/j.scr.2013.06.002] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2012] [Revised: 05/29/2013] [Accepted: 06/02/2013] [Indexed: 12/31/2022] Open
Abstract
Adipocyte stem cells (hASCs) can proliferate and self-renew and, due to their multipotent nature, they can differentiate into several tissue-specific lineages, making them ideal candidates for use in cell therapy. Most attempts to determine the mRNA profile of self-renewing or differentiating stem cells have made use of total RNA for gene expression analysis. Several lines of evidence suggest that self-renewal and differentiation are also dependent on the control of protein synthesis by posttranscriptional mechanisms. We used adipogenic differentiation as a model, to investigate the extent to which posttranscriptional regulation controlled gene expression in hASCs. We focused on the initial steps of differentiation and isolated both the total mRNA fraction and the subpopulation of mRNAs associated with translating ribosomes. We observed that adipogenesis is committed in the first days of induction and three days appears as the minimum time of induction necessary for efficient differentiation. RNA-seq analysis showed that a significant percentage of regulated mRNAs were posttranscriptionally controlled. Part of this regulation involves massive changes in transcript untranslated regions (UTR) length, with differential extension/reduction of the 3'UTR after induction. A slight correlation can be observed between the expression levels of differentially expressed genes and the 3'UTR length. When we considered association to polysomes, this correlation values increased. Changes in the half lives were related to the extension of the 3'UTR, with longer UTRs mainly stabilizing the transcripts. Thus, changes in the length of these extensions may be associated with changes in the ability to associate with polysomes or in half-life.
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Affiliation(s)
- Lucia Spangenberg
- Unidad de Bioinformática, Institut Pasteur Montevideo, Mataojo 2020, Montevideo 11400, Uruguay
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18
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Kuersten S, Radek A, Vogel C, Penalva LOF. Translation regulation gets its 'omics' moment. WILEY INTERDISCIPLINARY REVIEWS-RNA 2013; 4:617-30. [PMID: 23677826 DOI: 10.1002/wrna.1173] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Revised: 04/23/2013] [Accepted: 04/24/2013] [Indexed: 12/22/2022]
Abstract
The fate of cellular RNA is largely determined by complex networks of protein-RNA interactions through ribonucleoprotein (RNP) complexes. Despite their relatively short half-life, transcripts associate with many different proteins that process, modify, translate, and degrade the RNA. Following biogenesis some mRNPs are immediately directed to translation and produce proteins, but many are diverted and regulated by processes including miRNA-mediated mechanisms, transport and localization, as well as turnover. Because of this complex interplay estimates of steady-state expression by methods such as RNAseq alone cannot capture critical aspects of cellular fate, environmental response, tumorigenesis, or gene expression regulation. More selective and integrative tools are needed to measure protein-RNA complexes and the regulatory processes involved. One focus area is measurements of the transcriptome associated with ribosomes and translation. These so-called polysome or ribosome profiling techniques can evaluate translation efficiency as well as the interplay between translation initiation, elongation, and termination-subject areas not well understood at a systems biology level. Ribosome profiling is a highly promising technique that provides mRNA positional information of ribosome occupancy, potentially bridging the gap between gene expression (i.e., RNAseq and microarray analysis) and protein quantification (i.e., mass spectrometry). In combination with methods such as RNA immunoprecipitation, miRNA profiling, or proteomics, we obtain a fresh view of global post-transcriptional and translational gene regulation. In addition, these techniques also provide new insight into new regulatory elements, such as alternative open reading frames, and translation regulation under different conditions.
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Maston GA, Zhu LJ, Chamberlain L, Lin L, Fang M, Green MR. Non-canonical TAF complexes regulate active promoters in human embryonic stem cells. eLife 2012; 1:e00068. [PMID: 23150797 PMCID: PMC3490149 DOI: 10.7554/elife.00068] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2012] [Accepted: 08/26/2012] [Indexed: 12/23/2022] Open
Abstract
The general transcription factor TFIID comprises the TATA-box-binding protein (TBP) and approximately 14 TBP-associated factors (TAFs). Here we find, unexpectedly, that undifferentiated human embryonic stem cells (hESCs) contain only six TAFs (TAFs 2, 3, 5, 6, 7 and 11), whereas following differentiation all TAFs are expressed. Directed and global chromatin immunoprecipitation analyses reveal an unprecedented promoter occupancy pattern: most active genes are bound by only TAFs 3 and 5 along with TBP, whereas the remaining active genes are bound by TBP and all six hESC TAFs. Consistent with these results, hESCs contain a previously undescribed complex comprising TAFs 2, 6, 7, 11 and TBP. Altering the composition of hESC TAFs, either by depleting TAFs that are present or ectopically expressing TAFs that are absent, results in misregulated expression of pluripotency genes and induction of differentiation. Thus, the selective expression and use of TAFs underlies the ability of hESCs to self-renew.DOI:http://dx.doi.org/10.7554/eLife.00068.001.
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Affiliation(s)
- Glenn A Maston
- Programs in Gene Function and Expression and Molecular Medicine , University of Massachusetts Medical School , Worcester , United States ; Howard Hughes Medical Institute , Chevy Chase , United States
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Underhill GH. Stem cell bioengineering at the interface of systems-based models and high-throughput platforms. WILEY INTERDISCIPLINARY REVIEWS-SYSTEMS BIOLOGY AND MEDICINE 2012; 4:525-45. [DOI: 10.1002/wsbm.1189] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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21
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Alternative splicing: decoding an expansive regulatory layer. Curr Opin Cell Biol 2012; 24:323-32. [DOI: 10.1016/j.ceb.2012.03.005] [Citation(s) in RCA: 110] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2011] [Revised: 01/27/2012] [Accepted: 03/08/2012] [Indexed: 12/14/2022]
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