1
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Tan CH, Wang TY, Park H, Lomenick B, Chou TF, Sternberg PW. Single-tissue proteomics in Caenorhabditis elegans reveals proteins resident in intestinal lysosome-related organelles. Proc Natl Acad Sci U S A 2024; 121:e2322588121. [PMID: 38861598 PMCID: PMC11194598 DOI: 10.1073/pnas.2322588121] [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: 12/25/2023] [Accepted: 05/06/2024] [Indexed: 06/13/2024] Open
Abstract
The nematode intestine is the primary site for nutrient uptake and storage as well as the synthesis of biomolecules; lysosome-related organelles known as gut granules are important for many of these functions. Aspects of intestine biology are not well understood, including the export of the nutrients it imports and the molecules it synthesizes, as well as the complete functions and protein content of the gut granules. Here, we report a mass spectrometry (MS)-based proteomic analysis of the intestine of the Caenorhabditis elegans and of its gut granules. Overall, we identified approximately 5,000 proteins each in the intestine and the gonad and showed that most of these proteins can be detected in samples extracted from a single worm, suggesting the feasibility of individual-level genetic analysis using proteomes. Comparing proteomes and published transcriptomes of the intestine and the gonad, we identified proteins that appear to be synthesized in the intestine and then transferred to the gonad. To identify gut granule proteins, we compared the proteome of individual intestines deficient in gut granules to the wild type. The identified gut granule proteome includes proteins known to be exclusively localized to the granules and additional putative gut granule proteins. We selected two of these putative gut granule proteins for validation via immunohistochemistry, and our successful confirmation of both suggests that our strategy was effective in identifying the gut granule proteome. Our results demonstrate the practicability of single-tissue MS-based proteomic analysis in small organisms and in its future utility.
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Affiliation(s)
- Chieh-Hsiang Tan
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125
| | - Ting-Yu Wang
- Proteome Exploration Laboratory, Beckman Institute, California Institute of Technology, Pasadena, CA 91125
| | - Heenam Park
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125
| | - Brett Lomenick
- Proteome Exploration Laboratory, Beckman Institute, California Institute of Technology, Pasadena, CA 91125
| | - Tsui-Fen Chou
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125
- Proteome Exploration Laboratory, Beckman Institute, California Institute of Technology, Pasadena, CA 91125
| | - Paul W Sternberg
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125
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2
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Pollex T, Marco-Ferreres R, Ciglar L, Ghavi-Helm Y, Rabinowitz A, Viales RR, Schaub C, Jankowski A, Girardot C, Furlong EEM. Chromatin gene-gene loops support the cross-regulation of genes with related function. Mol Cell 2024; 84:822-838.e8. [PMID: 38157845 DOI: 10.1016/j.molcel.2023.12.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 10/31/2023] [Accepted: 12/14/2023] [Indexed: 01/03/2024]
Abstract
Chromatin loops between gene pairs have been observed in diverse contexts in both flies and vertebrates. Combining high-resolution Capture-C, DNA fluorescence in situ hybridization, and genetic perturbations, we dissect the functional role of three loops between genes with related function during Drosophila embryogenesis. By mutating the loop anchor (but not the gene) or the gene (but not loop anchor), we disentangle loop formation and gene expression and show that the 3D proximity of paralogous gene loci supports their co-regulation. Breaking the loop leads to either an attenuation or enhancement of expression and perturbs their relative levels of expression and cross-regulation. Although many loops appear constitutive across embryogenesis, their function can change in different developmental contexts. Taken together, our results indicate that chromatin gene-gene loops act as architectural scaffolds that can be used in different ways in different contexts to fine-tune the coordinated expression of genes with related functions and sustain their cross-regulation.
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Affiliation(s)
- Tim Pollex
- European Molecular Biology Laboratory (EMBL), Genome Biology Unit, 69117 Heidelberg, Germany
| | - Raquel Marco-Ferreres
- European Molecular Biology Laboratory (EMBL), Genome Biology Unit, 69117 Heidelberg, Germany
| | - Lucia Ciglar
- European Molecular Biology Laboratory (EMBL), Genome Biology Unit, 69117 Heidelberg, Germany
| | - Yad Ghavi-Helm
- European Molecular Biology Laboratory (EMBL), Genome Biology Unit, 69117 Heidelberg, Germany
| | - Adam Rabinowitz
- European Molecular Biology Laboratory (EMBL), Genome Biology Unit, 69117 Heidelberg, Germany
| | | | - Christoph Schaub
- European Molecular Biology Laboratory (EMBL), Genome Biology Unit, 69117 Heidelberg, Germany
| | - Aleksander Jankowski
- European Molecular Biology Laboratory (EMBL), Genome Biology Unit, 69117 Heidelberg, Germany
| | - Charles Girardot
- European Molecular Biology Laboratory (EMBL), Genome Biology Unit, 69117 Heidelberg, Germany
| | - Eileen E M Furlong
- European Molecular Biology Laboratory (EMBL), Genome Biology Unit, 69117 Heidelberg, Germany.
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3
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Nisaa K, Ben-Zvi A. HLH-1 Modulates Muscle Proteostasis During Caenorhabditis elegans Larval Development. Front Cell Dev Biol 2022; 10:920569. [PMID: 35733850 PMCID: PMC9207508 DOI: 10.3389/fcell.2022.920569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Accepted: 05/18/2022] [Indexed: 11/13/2022] Open
Abstract
Muscle proteostasis is shaped by the myogenic transcription factor MyoD which regulates the expression of chaperones during muscle differentiation. Whether MyoD can also modulate chaperone expression in terminally differentiated muscle cells remains open. Here we utilized a temperature-sensitive (ts) conditional knockdown nonsense mutation in MyoD ortholog in C. elegans, HLH-1, to ask whether MyoD plays a role in maintaining muscle proteostasis post myogenesis. We showed that hlh-1 is expressed during larval development and that hlh-1 knockdown at the first, second, or third larval stages resulted in severe defects in motility and muscle organization. Motility defects and myofilament organization were rescued when the clearance of hlh-1(ts) mRNA was inhibited, and hlh-1 mRNA levels were restored. Moreover, hlh-1 knockdown modulated the expression of chaperones with putative HLH-1 binding sites in their promoters, supporting HLH-1 role in muscle maintenance during larval development. Finally, mild disruption of hlh-1 expression during development resulted in earlier dysregulation of muscle maintenance and function during adulthood. We propose that the differentiation transcription factor, HLH-1, contributes to muscle maintenance and regulates cell-specific chaperone expression post differentiation. HLH-1 may thus impact muscle proteostasis and potentially the onset and manifestation of sarcopenia.
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Affiliation(s)
| | - Anat Ben-Zvi
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
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4
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Chen Z, Huang X, Fu R, Zhan A. Neighbours matter: Effects of genomic organization on gene expression plasticity in response to environmental stresses during biological invasions. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. PART D, GENOMICS & PROTEOMICS 2022; 42:100992. [PMID: 35504120 DOI: 10.1016/j.cbd.2022.100992] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 04/07/2022] [Accepted: 04/21/2022] [Indexed: 06/14/2023]
Abstract
Gene expression regulation has been widely recognized as an important molecular mechanism underlying phenotypic plasticity in environmental adaptation. However, it remains largely unexplored on the effects of genomic organization on gene expression plasticity under environmental stresses during biological invasions. Here, we use an invasive model ascidian, Ciona robusta, to investigate how genomic organization affects gene expression in response to salinity stresses during range expansions. Our study showed that neighboring genes were co-expressed and approximately 30% of stress responsive genes were physically clustered on chromosomes. Such coordinated expression was substantially affected by the physical distance and orientation of genes. Interestingly, the overall expression correlation of neighboring genes was significantly decreased under high salinity stresses, illustrating that the co-expression regulation could be disrupted by salinity challenges. Furthermore, the clustering of genes was associated with their function constraints and expression patterns - operon genes enriched in gene expression machinery had the highest transcriptional activity and expression stability. Notably, our analyses showed that the tail-to-tail genes, mainly involved in biological functions related to phosphorylation, homeostatic process, and ion transport, exhibited higher intrinsic expression variability and greater response to salinity challenges. Altogether, the results obtained here provide new insights into the effects of gene organization on gene expression plasticity under environmental challenges, hence improving our knowledge on mechanisms of rapid environmental adaptation during biological invasions.
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Affiliation(s)
- Zaohuang Chen
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Haidian District, Beijing 100085, China; University of Chinese Academy of Sciences, Chinese Academy of Sciences, 19A Yuquan Road, Shijingshan District, Beijing 100049, China
| | - Xuena Huang
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Haidian District, Beijing 100085, China
| | - Ruiying Fu
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Haidian District, Beijing 100085, China; University of Chinese Academy of Sciences, Chinese Academy of Sciences, 19A Yuquan Road, Shijingshan District, Beijing 100049, China
| | - Aibin Zhan
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Haidian District, Beijing 100085, China; University of Chinese Academy of Sciences, Chinese Academy of Sciences, 19A Yuquan Road, Shijingshan District, Beijing 100049, China.
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5
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Corbacho J, Sanabria-Reinoso E, Buono L, Fernández-Miñan A, Martínez-Morales JR. Trap-TRAP, a Versatile Tool for Tissue-Specific Translatomics in Zebrafish. Front Cell Dev Biol 2022; 9:817191. [PMID: 35174174 PMCID: PMC8841413 DOI: 10.3389/fcell.2021.817191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 12/24/2021] [Indexed: 11/13/2022] Open
Abstract
Developmental and physiological processes depend on the transcriptional and translational activity of heterogeneous cell populations. A main challenge in gene expression studies is dealing with this intrinsic complexity while keeping sequencing efficiency. Translating ribosome affinity purification (TRAP) methods have allowed cell-specific recovery of polyribosome-associated RNAs by genetic tagging of ribosomes in selected cell populations. Here we combined the TRAP approach with adapted enhancer trap methods (trap-TRAP) to systematically generate zebrafish transgenic lines suitable for tissue-specific translatome interrogation. Through the random integration of a GFP-tagged version of the large subunit ribosomal protein L10a (EGFP-Rpl10a), we have generated stable lines driving expression in a variety of tissues, including the retina, skeletal muscle, lateral line primordia, rhombomeres, or jaws. To increase the range of applications, a UAS:TRAP transgenic line compatible with available Gal4 lines was also generated and tested. The resulting collection of lines and applications constitutes a resource for the zebrafish community in developmental genetics, organ physiology and disease modelling.
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6
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Zečić A, Dhondt I, Braeckman BP. Accumulation of Glycogen and Upregulation of LEA-1 in C. elegans daf-2(e1370) Support Stress Resistance, Not Longevity. Cells 2022; 11:245. [PMID: 35053361 PMCID: PMC8773926 DOI: 10.3390/cells11020245] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 12/26/2021] [Accepted: 01/07/2022] [Indexed: 02/04/2023] Open
Abstract
DAF-16-dependent activation of a dauer-associated genetic program in the C. elegans insulin/IGF-1 daf-2(e1370) mutant leads to accumulation of large amounts of glycogen with concomitant upregulation of glycogen synthase, GSY-1. Glycogen is a major storage sugar in C. elegans that can be used as a short-term energy source for survival, and possibly as a reservoir for synthesis of a chemical chaperone trehalose. Its role in mitigating anoxia, osmotic and oxidative stress has been demonstrated previously. Furthermore, daf-2 mutants show increased abundance of the group 3 late embryogenesis abundant protein LEA-1, which has been found to act in synergy with trehalose to exert its protective role against desiccation and heat stress in vitro, and to be essential for desiccation tolerance in C. elegans dauer larvae. Here we demonstrate that accumulated glycogen is not required for daf-2 longevity, but specifically protects against hyperosmotic stress, and serves as an important energy source during starvation. Similarly, lea-1 does not act to support daf-2 longevity. Instead, it contributes to increased resistance of daf-2 mutants to heat, osmotic, and UV stress. In summary, our experimental results suggest that longevity and stress resistance can be uncoupled in IIS longevity mutants.
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Affiliation(s)
| | | | - Bart P. Braeckman
- Laboratory of Aging Physiology and Molecular Evolution, Department of Biology, Ghent University, K. L. Ledeganckstraat 35, B-9000 Ghent, Belgium; (A.Z.); (I.D.)
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7
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Dechaud C, Miyake S, Martinez-Bengochea A, Schartl M, Volff JN, Naville M. Clustering of Sex-Biased Genes and Transposable Elements in the Genome of the Medaka Fish Oryzias latipes. Genome Biol Evol 2021; 13:6384576. [PMID: 34623422 PMCID: PMC8633743 DOI: 10.1093/gbe/evab230] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/04/2021] [Indexed: 12/17/2022] Open
Abstract
Although genes with similar expression patterns are sometimes found in the same genomic regions, almost nothing is known about the relative organization in genomes of genes and transposable elements (TEs), which might influence each other at the regulatory level. In this study, we used transcriptomic data from male and female gonads of the Japanese medaka Oryzias latipes to define sexually biased genes and TEs and analyze their relative genomic localization. We identified 20,588 genes expressed in the adult gonads of O. latipes. Around 39% of these genes are differentially expressed between male and female gonads. We further analyzed the expression of TEs using the program SQuIRE and showed that more TE copies are overexpressed in testis than in ovaries (36% vs. 10%, respectively). We then developed a method to detect genomic regions enriched in testis- or ovary-biased genes. This revealed that sex-biased genes and TEs are not randomly distributed in the genome and a part of them form clusters with the same expression bias. We also found a correlation of expression between TE copies and their closest genes, which increases with decreasing intervening distance. Such a genomic organization suggests either that TEs hijack the regulatory sequences of neighboring sexual genes, allowing their expression in germ line cells and consequently new insertions to be transmitted to the next generation, or that TEs are involved in the regulation of sexual genes, and might therefore through their mobility participate in the rewiring of sex regulatory networks.
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Affiliation(s)
- Corentin Dechaud
- Institut de Genomique Fonctionnelle de Lyon, Univ Lyon, CNRS UMR 5242, Ecole Normale Superieure de Lyon, Universite Claude Bernard Lyon 1, Lyon, France
| | - Sho Miyake
- Institut de Genomique Fonctionnelle de Lyon, Univ Lyon, CNRS UMR 5242, Ecole Normale Superieure de Lyon, Universite Claude Bernard Lyon 1, Lyon, France
| | | | - Manfred Schartl
- Entwicklungsbiochemie, Biozentrum, Universität Würzburg, Würzburg, Germany.,Department of Chemistry and Biochemistry, The Xiphophorus Genetic Stock Center, Texas State University, San Marcos, Texas, USA
| | - Jean-Nicolas Volff
- Institut de Genomique Fonctionnelle de Lyon, Univ Lyon, CNRS UMR 5242, Ecole Normale Superieure de Lyon, Universite Claude Bernard Lyon 1, Lyon, France
| | - Magali Naville
- Institut de Genomique Fonctionnelle de Lyon, Univ Lyon, CNRS UMR 5242, Ecole Normale Superieure de Lyon, Universite Claude Bernard Lyon 1, Lyon, France
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8
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Gravitational Force-Induced 3D Chromosomal Conformational Changes Are Associated with Rapid Transcriptional Response in Human T Cells. Int J Mol Sci 2021; 22:ijms22179426. [PMID: 34502336 PMCID: PMC8430767 DOI: 10.3390/ijms22179426] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 08/26/2021] [Accepted: 08/27/2021] [Indexed: 12/14/2022] Open
Abstract
The mechanisms underlying gravity perception in mammalian cells are unknown. We have recently discovered that the transcriptome of cells in the immune system, which is the most affected system during a spaceflight, responds rapidly and broadly to altered gravity. To pinpoint potential underlying mechanisms, we compared gene expression and three-dimensional (3D) chromosomal conformational changes in human Jurkat T cells during the short-term gravitational changes in parabolic flight and suborbital ballistic rocket flight experiments. We found that differential gene expression in gravity-responsive chromosomal regions, but not differentially regulated single genes, are highly conserved between different real altered gravity comparisons. These coupled gene expression effects in chromosomal regions could be explained by underlying chromatin structures. Based on a high-throughput chromatin conformation capture (Hi-C) analysis in altered gravity, we found that small chromosomes (chr16–22, with the exception of chr18) showed increased intra- and interchromosomal interactions in altered gravity, whereby large chromosomes showed decreased interactions. Finally, we detected a nonrandom overlap between Hi-C-identified chromosomal interacting regions and gravity-responsive chromosomal regions (GRCRs). We therefore demonstrate the first evidence that gravitational force-induced 3D chromosomal conformational changes are associated with rapid transcriptional response in human T cells. We propose a general model of cellular sensitivity to gravitational forces, where gravitational forces acting on the cellular membrane are rapidly and mechanically transduced through the cytoskeleton into the nucleus, moving chromosome territories to new conformation states and their genes into more expressive or repressive environments, finally resulting in region-specific differential gene expression.
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9
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Hrach HC, O'Brien S, Steber HS, Newbern J, Rawls A, Mangone M. Transcriptome changes during the initiation and progression of Duchenne muscular dystrophy in Caenorhabditis elegans. Hum Mol Genet 2021; 29:1607-1623. [PMID: 32227114 PMCID: PMC7322572 DOI: 10.1093/hmg/ddaa055] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 02/17/2020] [Accepted: 03/23/2020] [Indexed: 12/21/2022] Open
Abstract
Duchenne muscular dystrophy (DMD) is a lethal, X-linked disease characterized by progressive muscle degeneration. The condition is driven by nonsense and missense mutations in the dystrophin gene, leading to instability of the sarcolemma and skeletal muscle necrosis and atrophy. Resulting changes in muscle-specific gene expression that take place in dystrophin's absence remain largely uncharacterized, as they are potentially obscured by the chronic inflammation elicited by muscle damage in humans. Caenorhabditis elegans possess a mild inflammatory response that is not active in the muscle, and lack a satellite cell equivalent. This allows for the characterization of the transcriptome rearrangements affecting disease progression independently of inflammation and regeneration. In effort to better understand these dynamics, we have isolated and sequenced body muscle-specific transcriptomes from C. elegans lacking functional dystrophin at distinct stages of disease progression. We have identified an upregulation of genes involved in mitochondrial function early in disease progression, and an upregulation of genes related to muscle repair in later stages. Our results suggest that in C. elegans, dystrophin may have a signaling role early in development, and its absence may activate compensatory mechanisms that counteract muscle degradation caused by loss of dystrophin. We have also developed a temperature-based screening method for synthetic paralysis that can be used to rapidly identify genetic partners of dystrophin. Our results allow for the comprehensive identification of transcriptome changes that potentially serve as independent drivers of disease progression and may in turn allow for the identification of new therapeutic targets for the treatment of DMD.
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Affiliation(s)
- Heather C Hrach
- Molecular and Cellular Biology Graduate Program, School of Life Sciences, 427 East Tyler Mall, Tempe, AZ 85287 4501, USA.,Virginia G. Piper Center for Personalized Diagnostics, The Biodesign Institute at Arizona State University, 1001 S McAllister Ave, Tempe, AZ 85281, USA
| | - Shannon O'Brien
- Virginia G. Piper Center for Personalized Diagnostics, The Biodesign Institute at Arizona State University, 1001 S McAllister Ave, Tempe, AZ 85281, USA.,Barrett Honors College, Arizona State University, 751 E Lemon Mall, Tempe, AZ 85281, USA
| | - Hannah S Steber
- Barrett Honors College, Arizona State University, 751 E Lemon Mall, Tempe, AZ 85281, USA
| | - Jason Newbern
- School of Life Sciences, 427 East Tyler Mall, Tempe, AZ 85287 4501, USA
| | - Alan Rawls
- School of Life Sciences, 427 East Tyler Mall, Tempe, AZ 85287 4501, USA
| | - Marco Mangone
- Virginia G. Piper Center for Personalized Diagnostics, The Biodesign Institute at Arizona State University, 1001 S McAllister Ave, Tempe, AZ 85281, USA
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10
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Duncan EJ, Leask MP, Dearden PK. Genome Architecture Facilitates Phenotypic Plasticity in the Honeybee (Apis mellifera). Mol Biol Evol 2021; 37:1964-1978. [PMID: 32134461 PMCID: PMC7306700 DOI: 10.1093/molbev/msaa057] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Phenotypic plasticity, the ability of an organism to alter its phenotype in response to an environmental cue, facilitates rapid adaptation to changing environments. Plastic changes in morphology and behavior are underpinned by widespread gene expression changes. However, it is unknown if, or how, genomes are structured to ensure these robust responses. Here, we use repression of honeybee worker ovaries as a model of plasticity. We show that the honeybee genome is structured with respect to plasticity; genes that respond to an environmental trigger are colocated in the honeybee genome in a series of gene clusters, many of which have been assembled in the last 80 My during the evolution of the Apidae. These clusters are marked by histone modifications that prefigure the gene expression changes that occur as the ovary activates, suggesting that these genomic regions are poised to respond plastically. That the linear sequence of the honeybee genome is organized to coordinate widespread gene expression changes in response to environmental influences and that the chromatin organization in these regions is prefigured to respond to these influences is perhaps unexpected and has implications for other examples of plasticity in physiology, evolution, and human disease.
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Affiliation(s)
- Elizabeth J Duncan
- Genomics Aotearoa and Biochemistry Department, University of Otago, Dunedin, New Zealand.,School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
| | - Megan P Leask
- Genomics Aotearoa and Biochemistry Department, University of Otago, Dunedin, New Zealand
| | - Peter K Dearden
- Genomics Aotearoa and Biochemistry Department, University of Otago, Dunedin, New Zealand
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11
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Zhao Z, Fan R, Xu W, Kou Y, Wang Y, Ma X, Du Z. Single-cell dynamics of chromatin activity during cell lineage differentiation in Caenorhabditis elegans embryos. Mol Syst Biol 2021; 17:e10075. [PMID: 33900055 PMCID: PMC8073016 DOI: 10.15252/msb.202010075] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 03/22/2021] [Accepted: 03/23/2021] [Indexed: 11/09/2022] Open
Abstract
Elucidating the chromatin dynamics that orchestrate embryogenesis is a fundamental question in developmental biology. Here, we exploit position effects on expression as an indicator of chromatin activity and infer the chromatin activity landscape in every lineaged cell during Caenorhabditis elegans early embryogenesis. Systems-level analyses reveal that chromatin activity distinguishes cellular states and correlates with fate patterning in the early embryos. As cell lineage unfolds, chromatin activity diversifies in a lineage-dependent manner, with switch-like changes accompanying anterior-posterior fate asymmetry and characteristic landscapes being established in different cell lineages. Upon tissue differentiation, cellular chromatin from distinct lineages converges according to tissue types but retains stable memories of lineage history, contributing to intra-tissue cell heterogeneity. However, the chromatin landscapes of cells organized in a left-right symmetric pattern are predetermined to be analogous in early progenitors so as to pre-set equivalent states. Finally, genome-wide analysis identifies many regions exhibiting concordant chromatin activity changes that mediate the co-regulation of functionally related genes during differentiation. Collectively, our study reveals the developmental and genomic dynamics of chromatin activity at the single-cell level.
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Affiliation(s)
- Zhiguang Zhao
- State Key Laboratory of Molecular Developmental BiologyInstitute of Genetics and Developmental BiologyChinese Academy of SciencesBeijingChina
- University of Chinese Academy of SciencesBeijingChina
| | - Rong Fan
- State Key Laboratory of Molecular Developmental BiologyInstitute of Genetics and Developmental BiologyChinese Academy of SciencesBeijingChina
- University of Chinese Academy of SciencesBeijingChina
| | - Weina Xu
- State Key Laboratory of Molecular Developmental BiologyInstitute of Genetics and Developmental BiologyChinese Academy of SciencesBeijingChina
- University of Chinese Academy of SciencesBeijingChina
| | - Yahui Kou
- State Key Laboratory of Molecular Developmental BiologyInstitute of Genetics and Developmental BiologyChinese Academy of SciencesBeijingChina
- University of Chinese Academy of SciencesBeijingChina
| | - Yangyang Wang
- State Key Laboratory of Molecular Developmental BiologyInstitute of Genetics and Developmental BiologyChinese Academy of SciencesBeijingChina
| | - Xuehua Ma
- State Key Laboratory of Molecular Developmental BiologyInstitute of Genetics and Developmental BiologyChinese Academy of SciencesBeijingChina
| | - Zhuo Du
- State Key Laboratory of Molecular Developmental BiologyInstitute of Genetics and Developmental BiologyChinese Academy of SciencesBeijingChina
- University of Chinese Academy of SciencesBeijingChina
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12
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Buddika K, Xu J, Ariyapala IS, Sokol NS. I-KCKT allows dissection-free RNA profiling of adult Drosophila intestinal progenitor cells. Development 2021; 148:dev196568. [PMID: 33246929 PMCID: PMC7803463 DOI: 10.1242/dev.196568] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 11/19/2021] [Indexed: 12/13/2022]
Abstract
The adult Drosophila intestinal epithelium is a model system for stem cell biology, but its utility is limited by current biochemical methods that lack cell type resolution. Here, we describe a new proximity-based profiling method that relies upon a GAL4 driver, termed intestinal-kickout-GAL4 (I-KCKT-GAL4), that is exclusively expressed in intestinal progenitor cells. This method uses UV crosslinked whole animal frozen powder as its starting material to immunoprecipitate the RNA cargoes of transgenic epitope-tagged RNA binding proteins driven by I-KCKT-GAL4 When applied to the general mRNA-binder, poly(A)-binding protein, the RNA profile obtained by this method identifies 98.8% of transcripts found after progenitor cell sorting, and has low background noise despite being derived from whole animal lysate. We also mapped the targets of the more selective RNA binder, Fragile X mental retardation protein (FMRP), using enhanced crosslinking and immunoprecipitation (eCLIP), and report for the first time its binding motif in Drosophila cells. This method will therefore enable the RNA profiling of wild-type and mutant intestinal progenitor cells from intact flies exposed to normal and altered environments, as well as the identification of RNA-protein interactions crucial for stem cell function.
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Affiliation(s)
- Kasun Buddika
- Department of Biology, Indiana University, Bloomington, IN 47405, USA
| | - Jingjing Xu
- Department of Biology, Indiana University, Bloomington, IN 47405, USA
| | | | - Nicholas S Sokol
- Department of Biology, Indiana University, Bloomington, IN 47405, USA
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13
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Cockrum C, Kaneshiro KR, Rechtsteiner A, Tabuchi TM, Strome S. A primer for generating and using transcriptome data and gene sets. Development 2020; 147:147/24/dev193854. [PMID: 33361089 PMCID: PMC7774889 DOI: 10.1242/dev.193854] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Transcriptomic approaches have provided a growing set of powerful tools with which to study genome-wide patterns of gene expression. Rapidly evolving technologies enable analysis of transcript abundance data from particular tissues and even single cells. This Primer discusses methods that can be used to collect and profile RNAs from specific tissues or cells, process and analyze high-throughput RNA-sequencing data, and define sets of genes that accurately represent a category, such as tissue-enriched or tissue-specific gene expression. Summary: This Primer gives an overview of the considerations required when planning and conducting transcriptome profiling experiments, from sample isolation to data analysis and display, and discusses best practice in defining gene sets for use in addressing biological questions.
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Affiliation(s)
- Chad Cockrum
- Department of Molecular, Cell, and Developmental Biology, University of California Santa Cruz, 1156 High Street, Santa Cruz, CA 95064, USA
| | - Kiyomi R Kaneshiro
- Department of Molecular, Cell, and Developmental Biology, University of California Santa Cruz, 1156 High Street, Santa Cruz, CA 95064, USA
| | - Andreas Rechtsteiner
- Department of Molecular, Cell, and Developmental Biology, University of California Santa Cruz, 1156 High Street, Santa Cruz, CA 95064, USA
| | - Tomoko M Tabuchi
- Department of Molecular, Cell, and Developmental Biology, University of California Santa Cruz, 1156 High Street, Santa Cruz, CA 95064, USA
| | - Susan Strome
- Department of Molecular, Cell, and Developmental Biology, University of California Santa Cruz, 1156 High Street, Santa Cruz, CA 95064, USA
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14
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Tissue-Specific Transcription Footprinting Using RNA PoI DamID (RAPID) in Caenorhabditis elegans. Genetics 2020; 216:931-945. [PMID: 33037050 PMCID: PMC7768263 DOI: 10.1534/genetics.120.303774] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 10/09/2020] [Indexed: 11/23/2022] Open
Abstract
Differential gene expression across cell types underlies development and cell physiology in multicellular organisms. Caenorhabditis elegans is a powerful, extensively used model to address these biological questions. A remaining bottleneck relates to the difficulty to obtain comprehensive tissue-specific gene transcription data, since available methods are still challenging to execute and/or require large worm populations. Here, we introduce the RNA Polymerase DamID (RAPID) approach, in which the Dam methyltransferase is fused to a ubiquitous RNA polymerase subunit to create transcriptional footprints via methyl marks on the DNA of transcribed genes. To validate the method, we determined the polymerase footprints in whole animals, in sorted embryonic blastomeres and in different tissues from intact young adults by driving tissue-specific Dam fusion expression. We obtained meaningful transcriptional footprints in line with RNA-sequencing (RNA-seq) studies in whole animals or specific tissues. To challenge the sensitivity of RAPID and demonstrate its utility to determine novel tissue-specific transcriptional profiles, we determined the transcriptional footprints of the pair of XXX neuroendocrine cells, representing 0.2% of the somatic cell content of the animals. We identified 3901 candidate genes with putatively active transcription in XXX cells, including the few previously known markers for these cells. Using transcriptional reporters for a subset of new hits, we confirmed that the majority of them were expressed in XXX cells and identified novel XXX-specific markers. Taken together, our work establishes RAPID as a valid method for the determination of RNA polymerase footprints in specific tissues of C. elegans without the need for cell sorting or RNA tagging.
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15
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Arribere JA, Kuroyanagi H, Hundley HA. mRNA Editing, Processing and Quality Control in Caenorhabditis elegans. Genetics 2020; 215:531-568. [PMID: 32632025 PMCID: PMC7337075 DOI: 10.1534/genetics.119.301807] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 05/03/2020] [Indexed: 02/06/2023] Open
Abstract
While DNA serves as the blueprint of life, the distinct functions of each cell are determined by the dynamic expression of genes from the static genome. The amount and specific sequences of RNAs expressed in a given cell involves a number of regulated processes including RNA synthesis (transcription), processing, splicing, modification, polyadenylation, stability, translation, and degradation. As errors during mRNA production can create gene products that are deleterious to the organism, quality control mechanisms exist to survey and remove errors in mRNA expression and processing. Here, we will provide an overview of mRNA processing and quality control mechanisms that occur in Caenorhabditis elegans, with a focus on those that occur on protein-coding genes after transcription initiation. In addition, we will describe the genetic and technical approaches that have allowed studies in C. elegans to reveal important mechanistic insight into these processes.
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Affiliation(s)
| | - Hidehito Kuroyanagi
- Laboratory of Gene Expression, Medical Research Institute, Tokyo Medical and Dental University, Tokyo 113-8510, Japan, and
| | - Heather A Hundley
- Medical Sciences Program, Indiana University School of Medicine-Bloomington, Indiana 47405
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16
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Kaletsky R, Murphy CT. Transcriptional Profiling of C. elegans Adult Cells and Tissues with Age. Methods Mol Biol 2020; 2144:177-186. [PMID: 32410035 DOI: 10.1007/978-1-0716-0592-9_16] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Multicellular organisms are composed of distinct cells and tissues that coordinate highly orchestrated responses to environmental challenges, including those that arise with age. Since C. elegans is a premier model system used to study the molecular and cellular regulators of adult and aging phenotypes, cell type- and tissue-specific approaches are needed to characterize the genome-wide expression changes associated with these responses. Here we describe a method for the FACS-based isolation and RNA sequencing of dissociated cells from adult C. elegans. This technique is amenable to profiling the cell- and tissue-specific gene expression changes in C. elegans mutants, including aging models, such as the daf-2/insulin-like signaling (IIS) pathway, and in wild-type animals with age.
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Affiliation(s)
- Rachel Kaletsky
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA.,Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA
| | - Coleen T Murphy
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA. .,Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA.
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17
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Zhao T, Huan Q, Sun J, Liu C, Hou X, Yu X, Silverman IM, Zhang Y, Gregory BD, Liu CM, Qian W, Cao X. Impact of poly(A)-tail G-content on Arabidopsis PAB binding and their role in enhancing translational efficiency. Genome Biol 2019; 20:189. [PMID: 31481099 PMCID: PMC6724284 DOI: 10.1186/s13059-019-1799-8] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Accepted: 08/22/2019] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Polyadenylation plays a key role in producing mature mRNAs in eukaryotes. It is widely believed that the poly(A)-binding proteins (PABs) uniformly bind to poly(A)-tailed mRNAs, regulating their stability and translational efficiency. RESULTS We observe that the homozygous triple mutant of broadly expressed Arabidopsis thaliana PABs, AtPAB2, AtPAB4, and AtPAB8, is embryonic lethal. To understand the molecular basis, we characterize the RNA-binding landscape of these PABs. The AtPAB-binding efficiency varies over one order of magnitude among genes. To identify the sequences accounting for the variation, we perform poly(A)-seq that directly sequences the full-length poly(A) tails. More than 10% of poly(A) tails contain at least one guanosine (G); among them, the G-content varies from 0.8 to 28%. These guanosines frequently divide poly(A) tails into interspersed A-tracts and therefore cause the variation in the AtPAB-binding efficiency among genes. Ribo-seq and genome-wide RNA stability assays show that AtPAB-binding efficiency of a gene is positively correlated with translational efficiency rather than mRNA stability. Consistently, genes with stronger AtPAB binding exhibit a greater reduction in translational efficiency when AtPAB is depleted. CONCLUSIONS Our study provides a new mechanism that translational efficiency of a gene can be regulated through the G-content-dependent PAB binding, paving the way for a better understanding of poly(A) tail-associated regulation of gene expression.
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Affiliation(s)
- Taolan Zhao
- State Key Laboratory of Plant Genomics and National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China
- Key Laboratory of Genetic Network Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Qing Huan
- State Key Laboratory of Plant Genomics and National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China
- Key Laboratory of Genetic Network Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Jing Sun
- State Key Laboratory of Plant Genomics and National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Chunyan Liu
- State Key Laboratory of Plant Genomics and National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Xiuli Hou
- University of Chinese Academy of Sciences, Beijing, 100049, China
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Xiang Yu
- Department of Biology, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Ian M Silverman
- Department of Biology, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Yi Zhang
- Laboratory for Genome Regulation and Human Health and Center for Genome Analysis, ABLife Inc, Wuhan, 430075, Hubei, China
| | - Brian D Gregory
- Department of Biology, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Chun-Ming Liu
- University of Chinese Academy of Sciences, Beijing, 100049, China
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Wenfeng Qian
- State Key Laboratory of Plant Genomics and National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China.
- Key Laboratory of Genetic Network Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Xiaofeng Cao
- State Key Laboratory of Plant Genomics and National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
- CAS Center for Excellence in Molecular Plant Sciences, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China.
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18
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McLachlan IG, Flavell SW. Cell Type-specific mRNA Purification in Caenorhabditis elegans via Translating Ribosome Affinity Purification. Bio Protoc 2019; 9:e3328. [PMID: 33654835 DOI: 10.21769/bioprotoc.3328] [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: 05/30/2019] [Revised: 07/15/2019] [Accepted: 07/17/2019] [Indexed: 11/02/2022] Open
Abstract
Cell type-specific molecular profiling is widely used to gain new insights into the diverse cell types that make up complex biological tissues. Translating ribosome affinity purification (TRAP) is a method in which the cell type-specific expression of epitope-tagged ribosomal subunits allows one to purify actively translating mRNAs without the need for cell sorting or fixation. We adapted this method for use in C. elegans to identify novel transcripts in single cell types or to identify the effects of environmental changes on the transcriptomes of larger cohorts of cells. In this protocol, we describe methods to generate transgenic animals bearing tagged ribosomes in cells of interest, prepare these animals for immunoprecipitation, purify ribosome-mRNA complexes, and obtain purified mRNA for next-generation sequencing.
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Affiliation(s)
- Ian G McLachlan
- Department of Brain and Cognitive Sciences, Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Steven W Flavell
- Department of Brain and Cognitive Sciences, Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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19
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Rechtsteiner A, Costello ME, Egelhofer TA, Garrigues JM, Strome S, Petrella LN. Repression of Germline Genes in Caenorhabditis elegans Somatic Tissues by H3K9 Dimethylation of Their Promoters. Genetics 2019; 212:125-140. [PMID: 30910798 PMCID: PMC6499516 DOI: 10.1534/genetics.118.301878] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Accepted: 03/16/2019] [Indexed: 12/20/2022] Open
Abstract
Repression of germline-promoting genes in somatic cells is critical for somatic development and function. To study how germline genes are repressed in somatic tissues, we analyzed key histone modifications in three Caenorhabditis elegans synMuv B mutants, lin-15B, lin-35, and lin-37-all of which display ectopic expression of germline genes in the soma. LIN-35 and LIN-37 are members of the conserved DREAM complex. LIN-15B has been proposed to work with the DREAM complex but has not been shown biochemically to be a member of the complex. We found that, in wild-type worms, synMuv B target genes and germline genes are enriched for the repressive histone modification dimethylation of histone H3 on lysine 9 (H3K9me2) at their promoters. Genes with H3K9me2 promoter localization are evenly distributed across the autosomes, not biased toward autosomal arms, as are the broad H3K9me2 domains. Both synMuv B targets and germline genes display a dramatic reduction of H3K9me2 promoter localization in lin-15B mutants, but much weaker reduction in lin-35 and lin-37 mutants. This difference between lin-15B and DREAM complex mutants likely represents a difference in molecular function for these synMuv B proteins. In support of the pivotal role of H3K9me2 in regulation of germline genes by LIN-15B, global loss of H3K9me2 but not H3K9me3 results in phenotypes similar to synMuv B mutants, high-temperature larval arrest, and ectopic expression of germline genes in the soma. We propose that LIN-15B-driven enrichment of H3K9me2 at promoters of germline genes contributes to repression of those genes in somatic tissues.
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Affiliation(s)
- Andreas Rechtsteiner
- Department of Molecular, Cell, and Developmental Biology, University of California Santa Cruz, Santa Cruz, California 95064
| | - Meghan E Costello
- Department of Biological Sciences, Marquette University, Milwaukee, Wisconsin 53201
| | - Thea A Egelhofer
- Department of Molecular, Cell, and Developmental Biology, University of California Santa Cruz, Santa Cruz, California 95064
| | - Jacob M Garrigues
- Department of Molecular, Cell, and Developmental Biology, University of California Santa Cruz, Santa Cruz, California 95064
| | - Susan Strome
- Department of Molecular, Cell, and Developmental Biology, University of California Santa Cruz, Santa Cruz, California 95064
| | - Lisa N Petrella
- Department of Biological Sciences, Marquette University, Milwaukee, Wisconsin 53201
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20
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Fenner BJ, Liu YC, Koh SK, Gao Y, Deng L, Beuerman RW, Zhou L, Theng JTS, Mehta JS. Mediators of Corneal Haze Following Implantation of Presbyopic Corneal Inlays. ACTA ACUST UNITED AC 2019; 60:868-876. [DOI: 10.1167/iovs.18-25761] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- Beau J. Fenner
- Singapore National Eye Centre, Singapore
- Singapore Eye Research Institute, Singapore
| | - Yu-Chi Liu
- Singapore National Eye Centre, Singapore
- Singapore Eye Research Institute, Singapore
- Eye Academic Clinical Program, Duke-NUS Graduate Medical School, Singapore
| | | | - Yan Gao
- Singapore Eye Research Institute, Singapore
| | - Lu Deng
- Department of Statistics and Applied Probability, National University of Singapore
| | - Roger W. Beuerman
- Singapore Eye Research Institute, Singapore
- Eye Academic Clinical Program, Duke-NUS Graduate Medical School, Singapore
- Neuroscience Signature Research Program, Duke-NUS Graduate Medical School, Singapore
| | - Lei Zhou
- Singapore Eye Research Institute, Singapore
- Eye Academic Clinical Program, Duke-NUS Graduate Medical School, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | | | - Jodhbir S. Mehta
- Singapore National Eye Centre, Singapore
- Singapore Eye Research Institute, Singapore
- Eye Academic Clinical Program, Duke-NUS Graduate Medical School, Singapore
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21
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Wan X, Zhou Y, Chan CM, Yang H, Yeung C, Chow KL. SRD-1 in AWA neurons is the receptor for female volatile sex pheromones in C. elegans males. EMBO Rep 2019; 20:embr.201846288. [PMID: 30792215 DOI: 10.15252/embr.201846288] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Revised: 12/29/2018] [Accepted: 01/22/2019] [Indexed: 01/23/2023] Open
Abstract
Pheromones are critical cues for attracting mating partners for successful reproduction. Sexually mature Caenorhabditis remanei virgin females and self-sperm-depleted Caenorhabditis elegans hermaphrodites produce volatile sex pheromones to attract adult males of both species from afar. The chemoresponsive receptor in males has remained unknown. Here, we show that the male chemotactic behavior requires amphid sensory neurons (AWA neurons) and the G-protein-coupled receptor SRD-1. SRD-1 expression in AWA neurons is sexually dimorphic, with the levels being high in males but undetectable in hermaphrodites. Notably, srd-1 mutant males lack the chemotactic response and pheromone-induced excitation of AWA neurons, both of which can be restored in males and hermaphrodites by AWA-specific srd-1 expression, and ectopic expression of srd-1 in AWB neurons in srd-1 mutants results in a repulsive behavioral response in both sexes. Furthermore, we show that the C-terminal region of SRD-1 confers species-specific differences in the ability to perceive sex pheromones between C. elegans and C. remanei These findings offer an excellent model for dissecting how a single G-protein-coupled receptor expressed in a dimorphic neural system contributes to sex-specific behaviors in animals.
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Affiliation(s)
- Xuan Wan
- Division of Life Science, The Hong Kong University of Science and Technology, Hong Kong, Hong Kong
| | - Yuan Zhou
- Division of Life Science, The Hong Kong University of Science and Technology, Hong Kong, Hong Kong
| | - Chung Man Chan
- Division of Life Science, The Hong Kong University of Science and Technology, Hong Kong, Hong Kong
| | - Hainan Yang
- Division of Life Science, The Hong Kong University of Science and Technology, Hong Kong, Hong Kong
| | - Christine Yeung
- Division of Life Science, The Hong Kong University of Science and Technology, Hong Kong, Hong Kong
| | - King L Chow
- Division of Life Science, The Hong Kong University of Science and Technology, Hong Kong, Hong Kong .,Department of Chemical and Biological Engineering, The Hong Kong University of Science and Technology, Hong Kong, Hong Kong.,Interdisciplinary Programs Office, The Hong Kong University of Science and Technology, Hong Kong, Hong Kong
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22
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Coraggio F, Püschel R, Marti A, Meister P. Polycomb and Notch signaling regulate cell proliferation potential during Caenorhabditis elegans life cycle. Life Sci Alliance 2019; 2:e201800170. [PMID: 30599047 PMCID: PMC6306570 DOI: 10.26508/lsa.201800170] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Revised: 12/17/2018] [Accepted: 12/18/2018] [Indexed: 12/27/2022] Open
Abstract
Stable cell fate is an essential feature for multicellular organisms in which individual cells achieve specialized functions. Caenorhabditis elegans is a great model to analyze the determinants of cell fate stability because of its invariant lineage. We present a tractable cell fate challenge system that uses the induction of fate-specifying transcription factors. We show that wild-type differentiated animals are highly resistant to fate challenge. Removal of heterochromatin marks showed marked differences: the absence of histone 3 lysine 9 methylation (H3K9) has no effect on fate stability, whereas Polycomb homolog mes-2 mutants lacking H3K27 methylation terminally arrest larval development upon fate challenge. Unexpectedly, the arrest correlated with widespread cell proliferation rather than transdifferentiation. Using a candidate RNAi larval arrest-rescue screen, we show that the LIN-12Notch pathway is essential for hyperplasia induction. Moreover, Notch signaling appears downstream of food-sensing pathways, as dauers and first larval stage diapause animals are resistant to fate challenge. Our results demonstrate an equilibrium between proliferation and differentiation regulated by Polycomb and Notch signaling in the soma during the nematode life cycle.
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Affiliation(s)
- Francesca Coraggio
- Cell Fate and Nuclear Organization, Institute of Cell Biology, University of Bern, Bern, Switzerland
- Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland
| | - Ringo Püschel
- Cell Fate and Nuclear Organization, Institute of Cell Biology, University of Bern, Bern, Switzerland
- Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland
| | - Alisha Marti
- Cell Fate and Nuclear Organization, Institute of Cell Biology, University of Bern, Bern, Switzerland
| | - Peter Meister
- Cell Fate and Nuclear Organization, Institute of Cell Biology, University of Bern, Bern, Switzerland
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23
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Kaletsky R, Yao V, Williams A, Runnels AM, Tadych A, Zhou S, Troyanskaya OG, Murphy CT. Transcriptome analysis of adult Caenorhabditis elegans cells reveals tissue-specific gene and isoform expression. PLoS Genet 2018; 14:e1007559. [PMID: 30096138 PMCID: PMC6105014 DOI: 10.1371/journal.pgen.1007559] [Citation(s) in RCA: 125] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Revised: 08/22/2018] [Accepted: 07/13/2018] [Indexed: 12/19/2022] Open
Abstract
The biology and behavior of adults differ substantially from those of developing animals, and cell-specific information is critical for deciphering the biology of multicellular animals. Thus, adult tissue-specific transcriptomic data are critical for understanding molecular mechanisms that control their phenotypes. We used adult cell-specific isolation to identify the transcriptomes of C. elegans' four major tissues (or "tissue-ome"), identifying ubiquitously expressed and tissue-specific "enriched" genes. These data newly reveal the hypodermis' metabolic character, suggest potential worm-human tissue orthologies, and identify tissue-specific changes in the Insulin/IGF-1 signaling pathway. Tissue-specific alternative splicing analysis identified a large set of collagen isoforms. Finally, we developed a machine learning-based prediction tool for 76 sub-tissue cell types, which we used to predict cellular expression differences in IIS/FOXO signaling, stage-specific TGF-β activity, and basal vs. memory-induced CREB transcription. Together, these data provide a rich resource for understanding the biology governing multicellular adult animals.
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Affiliation(s)
- Rachel Kaletsky
- Department of Molecular Biology, Princeton University, Princeton, New Jersey, United States of America
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, United States of America
| | - Victoria Yao
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, United States of America
- Department of Computer Science, Princeton University, Princeton, New Jersey, United States of America
| | - April Williams
- Department of Molecular Biology, Princeton University, Princeton, New Jersey, United States of America
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, United States of America
| | - Alexi M. Runnels
- Department of Molecular Biology, Princeton University, Princeton, New Jersey, United States of America
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, United States of America
| | - Alicja Tadych
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, United States of America
| | - Shiyi Zhou
- Department of Molecular Biology, Princeton University, Princeton, New Jersey, United States of America
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, United States of America
| | - Olga G. Troyanskaya
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, United States of America
- Department of Computer Science, Princeton University, Princeton, New Jersey, United States of America
- Flatiron Institute, Simons Foundation, New York, New York, United States of America
| | - Coleen T. Murphy
- Department of Molecular Biology, Princeton University, Princeton, New Jersey, United States of America
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, United States of America
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24
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Murray JI. Systems biology of embryonic development: Prospects for a complete understanding of the Caenorhabditis elegans embryo. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2018; 7:e314. [PMID: 29369536 DOI: 10.1002/wdev.314] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Revised: 12/01/2017] [Accepted: 12/12/2017] [Indexed: 01/07/2023]
Abstract
The convergence of developmental biology and modern genomics tools brings the potential for a comprehensive understanding of developmental systems. This is especially true for the Caenorhabditis elegans embryo because its small size, invariant developmental lineage, and powerful genetic and genomic tools provide the prospect of a cellular resolution understanding of messenger RNA (mRNA) expression and regulation across the organism. We describe here how a systems biology framework might allow large-scale determination of the embryonic regulatory relationships encoded in the C. elegans genome. This framework consists of two broad steps: (a) defining the "parts list"-all genes expressed in all cells at each time during development and (b) iterative steps of computational modeling and refinement of these models by experimental perturbation. Substantial progress has been made towards defining the parts list through imaging methods such as large-scale green fluorescent protein (GFP) reporter analysis. Imaging results are now being augmented by high-resolution transcriptome methods such as single-cell RNA sequencing, and it is likely the complete expression patterns of all genes across the embryo will be known within the next few years. In contrast, the modeling and perturbation experiments performed so far have focused largely on individual cell types or genes, and improved methods will be needed to expand them to the full genome and organism. This emerging comprehensive map of embryonic expression and regulatory function will provide a powerful resource for developmental biologists, and would also allow scientists to ask questions not accessible without a comprehensive picture. This article is categorized under: Invertebrate Organogenesis > Worms Technologies > Analysis of the Transcriptome Gene Expression and Transcriptional Hierarchies > Gene Networks and Genomics.
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Affiliation(s)
- John Isaac Murray
- Department of Genetics, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
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25
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QTL analysis of cocoon shell weight identifies BmRPL18 associated with silk protein synthesis in silkworm by pooling sequencing. Sci Rep 2017; 7:17985. [PMID: 29269837 PMCID: PMC5740181 DOI: 10.1038/s41598-017-18277-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Accepted: 12/07/2017] [Indexed: 01/17/2023] Open
Abstract
Mechanisms that regulate silk protein synthesis provide the basis for silkworm variety breeding and silk gland bioreactor optimization. Here, using the pooling sequencing-based methodology, we deciphered the genetic basis for the varied silk production in different silkworm strains. We identified 8 SNPs, with 6 on chromosome 11 and 1 each on chromosomes 22 and 23, that were linked with silk production. After conducting an association analysis between gene expression pattern, silk gland development and cocoon shell weight (CSW), BMGN011620 was found to be regulating silk production. BMGN011620 encodes the 60S ribosomal protein, L18, which is an indispensable component of the 60S ribosomal subunit; therefore we named it BmRPL18. Moreover, the clustering of linked SNPs on chromosome 11 and the analysis of differentially expressed genes reported in previous Omics studies indicated that the genes regulating silk protein synthesis may exhibit a clustering distribution in the silkworm genome. These results collectively advance our understanding of the regulation of silk production, including the role of ribosomal proteins and the clustered distribution of genes involved in silk protein synthesis.
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26
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Appocher C, Mohagheghi F, Cappelli S, Stuani C, Romano M, Feiguin F, Buratti E. Major hnRNP proteins act as general TDP-43 functional modifiers both in Drosophila and human neuronal cells. Nucleic Acids Res 2017; 45:8026-8045. [PMID: 28575377 PMCID: PMC5570092 DOI: 10.1093/nar/gkx477] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 05/16/2017] [Indexed: 12/13/2022] Open
Abstract
Nuclear factor TDP-43 is known to play an important role in several neurodegenerative pathologies. In general, TDP-43 is an abundant protein within the eukaryotic nucleus that binds to many coding and non-coding RNAs and influence their processing. Using Drosophila, we have performed a functional screening to establish the ability of major hnRNP proteins to affect TDP-43 overexpression/depletion phenotypes. Interestingly, we observed that lowering hnRNP and TDP-43 expression has a generally harmful effect on flies locomotor abilities. In parallel, our study has also identified a distinct set of hnRNPs that is capable of powerfully rescuing TDP-43 toxicity in the fly eye (Hrb27c, CG42458, Glo and Syp). Most importantly, removing the human orthologs of Hrb27c (DAZAP1) in human neuronal cell lines can correct several pre-mRNA splicing events altered by TDP-43 depletion. Moreover, using RNA sequencing analysis we show that DAZAP1 and TDP-43 can co-regulate an extensive number of biological processes and molecular functions potentially important for the neuron/motor neuron pathophysiology. Our results suggest that changes in hnRNP expression levels can significantly modulate TDP-43 functions and affect pathological outcomes.
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Affiliation(s)
- Chiara Appocher
- International Centre for Genetic Engineering and Biotechnology (ICGEB), 34149 Trieste, Italy
| | - Fatemeh Mohagheghi
- International Centre for Genetic Engineering and Biotechnology (ICGEB), 34149 Trieste, Italy
| | - Sara Cappelli
- International Centre for Genetic Engineering and Biotechnology (ICGEB), 34149 Trieste, Italy
| | - Cristiana Stuani
- International Centre for Genetic Engineering and Biotechnology (ICGEB), 34149 Trieste, Italy
| | - Maurizio Romano
- Department of Life Sciences, University of Trieste, Via A. Valerio 28, 34127 Trieste, Italy
| | - Fabian Feiguin
- International Centre for Genetic Engineering and Biotechnology (ICGEB), 34149 Trieste, Italy
| | - Emanuele Buratti
- International Centre for Genetic Engineering and Biotechnology (ICGEB), 34149 Trieste, Italy
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27
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Taxonomically Restricted Genes with Essential Functions Frequently Play Roles in Chromosome Segregation in Caenorhabditis elegans and Saccharomyces cerevisiae. G3-GENES GENOMES GENETICS 2017; 7:3337-3347. [PMID: 28839119 PMCID: PMC5633384 DOI: 10.1534/g3.117.300193] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Genes encoding essential components of core cellular processes are typically highly conserved across eukaryotes. However, a small proportion of essential genes are highly taxonomically restricted; there appear to be no similar genes outside the genomes of highly related species. What are the functions of these poorly characterized taxonomically restricted genes (TRGs)? Systematic screens in Saccharomyces cerevisiae and Caenorhabditis elegans previously identified yeast or nematode TRGs that are essential for viability and we find that these genes share many molecular features, despite having no significant sequence similarity. Specifically, we find that those TRGs with essential phenotypes have an expression profile more similar to highly conserved genes, they have more protein–protein interactions and more protein disorder. Surprisingly, many TRGs play central roles in chromosome segregation; a core eukaryotic process. We thus find that genes that appear to be highly evolutionarily restricted do not necessarily play roles in species-specific biological functions but frequently play essential roles in core eukaryotic processes.
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Soler-Oliva ME, Guerrero-Martínez JA, Bachetti V, Reyes JC. Analysis of the relationship between coexpression domains and chromatin 3D organization. PLoS Comput Biol 2017; 13:e1005708. [PMID: 28902867 PMCID: PMC5612749 DOI: 10.1371/journal.pcbi.1005708] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Revised: 09/25/2017] [Accepted: 08/03/2017] [Indexed: 01/08/2023] Open
Abstract
Gene order is not random in eukaryotic chromosomes, and co-regulated genes tend to be clustered. The mechanisms that determine co-regulation of large regions of the genome and its connection with chromatin three-dimensional (3D) organization are still unclear however. Here we have adapted a recently described method for identifying chromatin topologically associating domains (TADs) to identify coexpression domains (which we term “CODs”). Using human normal breast and breast cancer RNA-seq data, we have identified approximately 500 CODs. CODs in the normal and breast cancer genomes share similar characteristics but differ in their gene composition. COD genes have a greater tendency to be coexpressed with genes that reside in other CODs than with non-COD genes. Such inter-COD coexpression is maintained over large chromosomal distances in the normal genome but is partially lost in the cancer genome. Analyzing the relationship between CODs and chromatin 3D organization using Hi-C contact data, we find that CODs do not correspond to TADs. In fact, intra-TAD gene coexpression is the same as random for most chromosomes. However, the contact profile is similar between gene pairs that reside either in the same COD or in coexpressed CODs. These data indicate that co-regulated genes in the genome present similar patterns of contacts irrespective of the frequency of physical chromatin contacts between them. Prokaryotic operons normally comprise functionally related genes whose expression is coordinated. Even though operons do not exist in most eukaryotes, results from the last fifteen years indicate that gene order is nonetheless not random in eukaryotes, and that coexpressed genes tend to be grouped in the genome. We identify here about 500 coexpression domain (CODs) in normal breast tissue. Interestingly, we find that genes within CODs often are coexpressed with other genes that reside in other CODs placed very far away in the same chromosome, which is indicative of long-range inter-COD co-regulation. Furthermore, we find that coexpressed genes within CODs or within co-regulated CODs display similar three-dimensional chromatin contacts, suggesting a spatial coordination of CODs.
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Affiliation(s)
- María E. Soler-Oliva
- Centro Andaluz de Biología Molecular y Medicina Regenerativa-CABIMER, Consejo Superior de Investigaciones Científicas-Universidad de Sevilla-Universidad Pablo de Olavide (CSIC-USE-UPO), Sevilla, Spain
| | - José A. Guerrero-Martínez
- Centro Andaluz de Biología Molecular y Medicina Regenerativa-CABIMER, Consejo Superior de Investigaciones Científicas-Universidad de Sevilla-Universidad Pablo de Olavide (CSIC-USE-UPO), Sevilla, Spain
| | - Valentina Bachetti
- Centro Andaluz de Biología Molecular y Medicina Regenerativa-CABIMER, Consejo Superior de Investigaciones Científicas-Universidad de Sevilla-Universidad Pablo de Olavide (CSIC-USE-UPO), Sevilla, Spain
| | - José C. Reyes
- Centro Andaluz de Biología Molecular y Medicina Regenerativa-CABIMER, Consejo Superior de Investigaciones Científicas-Universidad de Sevilla-Universidad Pablo de Olavide (CSIC-USE-UPO), Sevilla, Spain
- * E-mail:
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29
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Gracida X, Calarco JA. Cell type-specific transcriptome profiling in C. elegans using the Translating Ribosome Affinity Purification technique. Methods 2017. [PMID: 28648677 DOI: 10.1016/j.ymeth.2017.06.023] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Organs and specific cell types execute specialized functions in multicellular organisms, in large part through customized gene expression signatures. Thus, profiling the transcriptomes of specific cell and tissue types remains an important tool for understanding how cells become specialized. Methodological approaches to detect gene expression differences have utilized samples from whole animals, dissected tissues, and more recently single cells. Despite these advances, there is still a challenge and a need in most laboratories to implement less invasive yet powerful cell-type specific transcriptome profiling methods. Here, we describe the use of the Translating Ribosome Affinity Purification (TRAP) method for C. elegans to detect cell type-specific gene expression patterns at the level of translating mRNAs. In TRAP, a ribosomal protein is fused to a tag (GFP) and is expressed under cell type-specific promoters to mark genetically defined cell types in vivo. Affinity purification of lysates of animals expressing the tag enriches for ribosome-associated mRNAs of the targeted tissue. The purified mRNAs are used for making cDNA libraries subjected to high-throughput sequencing to obtain genome-wide profiles of transcripts from the targeted cell type. The ease of exposing C. elegans to diverse stimuli, coupled with available cell type specific promoters, makes TRAP a useful approach to enable the discovery of molecular components in response to external or genetic perturbations.
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Affiliation(s)
- Xicotencatl Gracida
- FAS Center for Systems Biology, Harvard University, Cambridge, MA 02138, United States; Department of Organismal and Evolutionary Biology, Harvard University, Cambridge, MA 02138, United States.
| | - John A Calarco
- FAS Center for Systems Biology, Harvard University, Cambridge, MA 02138, United States; Department of Cell and Systems Biology, University of Toronto, Toronto M5S 3G5, Canada.
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Genome-Wide Temporal Expression Profiling in Caenorhabditis elegans Identifies a Core Gene Set Related to Long-Term Memory. J Neurosci 2017; 37:6661-6672. [PMID: 28592692 DOI: 10.1523/jneurosci.3298-16.2017] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Revised: 04/09/2017] [Accepted: 05/10/2017] [Indexed: 11/21/2022] Open
Abstract
The identification of genes related to encoding, storage, and retrieval of memories is a major interest in neuroscience. In the current study, we analyzed the temporal gene expression changes in a neuronal mRNA pool during an olfactory long-term associative memory (LTAM) in Caenorhabditis elegans hermaphrodites. Here, we identified a core set of 712 (538 upregulated and 174 downregulated) genes that follows three distinct temporal peaks demonstrating multiple gene regulation waves in LTAM. Compared with the previously published positive LTAM gene set (Lakhina et al., 2015), 50% of the identified upregulated genes here overlap with the previous dataset, possibly representing stimulus-independent memory-related genes. On the other hand, the remaining genes were not previously identified in positive associative memory and may specifically regulate aversive LTAM. Our results suggest a multistep gene activation process during the formation and retrieval of long-term memory and define general memory-implicated genes as well as conditioning-type-dependent gene sets.SIGNIFICANCE STATEMENT The identification of genes regulating different steps of memory is of major interest in neuroscience. Identification of common memory genes across different learning paradigms and the temporal activation of the genes are poorly studied. Here, we investigated the temporal aspects of Caenorhabditis elegans gene expression changes using aversive olfactory associative long-term memory (LTAM) and identified three major gene activation waves. Like in previous studies, aversive LTAM is also CREB dependent, and CREB activity is necessary immediately after training. Finally, we define a list of memory paradigm-independent core gene sets as well as conditioning-dependent genes.
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31
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Blazie SM, Geissel HC, Wilky H, Joshi R, Newbern J, Mangone M. Alternative Polyadenylation Directs Tissue-Specific miRNA Targeting in Caenorhabditis elegans Somatic Tissues. Genetics 2017; 206:757-774. [PMID: 28348061 PMCID: PMC5499184 DOI: 10.1534/genetics.116.196774] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 03/02/2017] [Indexed: 01/03/2023] Open
Abstract
mRNA expression dynamics promote and maintain the identity of somatic tissues in living organisms; however, their impact in post-transcriptional gene regulation in these processes is not fully understood. Here, we applied the PAT-Seq approach to systematically isolate, sequence, and map tissue-specific mRNA from five highly studied Caenorhabditis elegans somatic tissues: GABAergic and NMDA neurons, arcade and intestinal valve cells, seam cells, and hypodermal tissues, and studied their mRNA expression dynamics. The integration of these datasets with previously profiled transcriptomes of intestine, pharynx, and body muscle tissues, precisely assigns tissue-specific expression dynamics for 60% of all annotated C. elegans protein-coding genes, providing an important resource for the scientific community. The mapping of 15,956 unique high-quality tissue-specific polyA sites in all eight somatic tissues reveals extensive tissue-specific 3'untranslated region (3'UTR) isoform switching through alternative polyadenylation (APA) . Almost all ubiquitously transcribed genes use APA and harbor miRNA targets in their 3'UTRs, which are commonly lost in a tissue-specific manner, suggesting widespread usage of post-transcriptional gene regulation modulated through APA to fine tune tissue-specific protein expression. Within this pool, the human disease gene C. elegans orthologs rack-1 and tct-1 use APA to switch to shorter 3'UTR isoforms in order to evade miRNA regulation in the body muscle tissue, resulting in increased protein expression needed for proper body muscle function. Our results highlight a major positive regulatory role for APA, allowing genes to counteract miRNA regulation on a tissue-specific basis.
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Affiliation(s)
- Stephen M Blazie
- Molecular and Cellular Biology Graduate Program, Arizona State University, Tempe, Arizona 85281
- Virginia G. Piper Center for Personalized Diagnostics, The Biodesign Institute at Arizona State University, Tempe, Arizona 85281
| | - Heather C Geissel
- Molecular and Cellular Biology Graduate Program, Arizona State University, Tempe, Arizona 85281
- Virginia G. Piper Center for Personalized Diagnostics, The Biodesign Institute at Arizona State University, Tempe, Arizona 85281
| | - Henry Wilky
- Barrett Honors College, Arizona State University, Tempe, Arizona 85281
| | - Rajan Joshi
- College of Letters and Sciences, Interdisciplinary Studies, Biological Sciences and Informatics, Arizona State University, Tempe, Arizona 85281
| | - Jason Newbern
- Molecular and Cellular Biology Graduate Program, Arizona State University, Tempe, Arizona 85281
- Barrett Honors College, Arizona State University, Tempe, Arizona 85281
| | - Marco Mangone
- Molecular and Cellular Biology Graduate Program, Arizona State University, Tempe, Arizona 85281
- Virginia G. Piper Center for Personalized Diagnostics, The Biodesign Institute at Arizona State University, Tempe, Arizona 85281
- Barrett Honors College, Arizona State University, Tempe, Arizona 85281
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32
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Kachaev ZM, Gilmutdinov RA, Kopytova DV, Zheludkevich AA, Shidlovskii YV, Kurbidaeva AS. RNA immunoprecipitation technique for Drosophila melanogaster S2 cells. Mol Biol 2017. [DOI: 10.1134/s002689331606008x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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33
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A Differentiation Transcription Factor Establishes Muscle-Specific Proteostasis in Caenorhabditis elegans. PLoS Genet 2016; 12:e1006531. [PMID: 28036392 PMCID: PMC5201269 DOI: 10.1371/journal.pgen.1006531] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2016] [Accepted: 12/08/2016] [Indexed: 02/07/2023] Open
Abstract
Safeguarding the proteome is central to the health of the cell. In multi-cellular organisms, the composition of the proteome, and by extension, protein-folding requirements, varies between cells. In agreement, chaperone network composition differs between tissues. Here, we ask how chaperone expression is regulated in a cell type-specific manner and whether cellular differentiation affects chaperone expression. Our bioinformatics analyses show that the myogenic transcription factor HLH-1 (MyoD) can bind to the promoters of chaperone genes expressed or required for the folding of muscle proteins. To test this experimentally, we employed HLH-1 myogenic potential to genetically modulate cellular differentiation of Caenorhabditis elegans embryonic cells by ectopically expressing HLH-1 in all cells of the embryo and monitoring chaperone expression. We found that HLH-1-dependent myogenic conversion specifically induced the expression of putative HLH-1-regulated chaperones in differentiating muscle cells. Moreover, disrupting the putative HLH-1-binding sites on ubiquitously expressed daf-21(Hsp90) and muscle-enriched hsp-12.2(sHsp) promoters abolished their myogenic-dependent expression. Disrupting HLH-1 function in muscle cells reduced the expression of putative HLH-1-regulated chaperones and compromised muscle proteostasis during and after embryogenesis. In turn, we found that modulating the expression of muscle chaperones disrupted the folding and assembly of muscle proteins and thus, myogenesis. Moreover, muscle-specific over-expression of the DNAJB6 homolog DNJ-24, a limb-girdle muscular dystrophy-associated chaperone, disrupted the muscle chaperone network and exposed synthetic motility defects. We propose that cellular differentiation could establish a proteostasis network dedicated to the folding and maintenance of the muscle proteome. Such cell-specific proteostasis networks can explain the selective vulnerability that many diseases of protein misfolding exhibit even when the misfolded protein is ubiquitously expressed. Molecular chaperones protect proteins from misfolding and aggregation. In multi-cellular organisms, the composition and expression levels of chaperones vary between tissues. However, little is known of how such differential expression is regulated. We hypothesized that the cellular differentiation that regulates the cell-type specific expression program may be involved in establishing a cell-type specific chaperone network. To test this possibility, we addressed the myogenic commitment transcription factor HLH-1 (CeMyoD) that converts embryonic cells to muscle cells in Caenorhabditis elegans. We demonstrated that HLH-1 regulates the expression of muscle chaperones during muscle differentiation. Moreover, we showed that HLH-1-dependent expression of chaperones is required for embryonic development and muscle function. We propose that cellular differentiation results in cell-specific differences in the chaperone network that may be detrimental in terms of the susceptibility of neurons and muscle cells to protein misfolding diseases.
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34
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Quintero-Cadena P, Sternberg PW. Enhancer Sharing Promotes Neighborhoods of Transcriptional Regulation Across Eukaryotes. G3 (BETHESDA, MD.) 2016; 6:4167-4174. [PMID: 27799341 PMCID: PMC5144984 DOI: 10.1534/g3.116.036228] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Accepted: 10/15/2016] [Indexed: 01/08/2023]
Abstract
Enhancers physically interact with transcriptional promoters, looping over distances that can span multiple regulatory elements. Given that enhancer-promoter (EP) interactions generally occur via common protein complexes, it is unclear whether EP pairing is predominantly deterministic or proximity guided. Here, we present cross-organismic evidence suggesting that most EP pairs are compatible, largely determined by physical proximity rather than specific interactions. By reanalyzing transcriptome datasets, we find that the transcription of gene neighbors is correlated over distances that scale with genome size. We experimentally show that nonspecific EP interactions can explain such correlation, and that EP distance acts as a scaling factor for the transcriptional influence of an enhancer. We propose that enhancer sharing is commonplace among eukaryotes, and that EP distance is an important layer of information in gene regulation.
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Affiliation(s)
- Porfirio Quintero-Cadena
- Division of Biology and Biological Engineering, California Institute of Technology, Howard Hughes Medical Institute, Pasadena, California 91125
| | - Paul W Sternberg
- Division of Biology and Biological Engineering, California Institute of Technology, Howard Hughes Medical Institute, Pasadena, California 91125
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35
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Wang J, Ma Z, Carr SA, Mertins P, Zhang H, Zhang Z, Chan DW, Ellis MJC, Townsend RR, Smith RD, McDermott JE, Chen X, Paulovich AG, Boja ES, Mesri M, Kinsinger CR, Rodriguez H, Rodland KD, Liebler DC, Zhang B. Proteome Profiling Outperforms Transcriptome Profiling for Coexpression Based Gene Function Prediction. Mol Cell Proteomics 2016; 16:121-134. [PMID: 27836980 PMCID: PMC5217778 DOI: 10.1074/mcp.m116.060301] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Revised: 11/07/2016] [Indexed: 01/05/2023] Open
Abstract
Coexpression of mRNAs under multiple conditions is commonly used to infer cofunctionality of their gene products despite well-known limitations of this "guilt-by-association" (GBA) approach. Recent advancements in mass spectrometry-based proteomic technologies have enabled global expression profiling at the protein level; however, whether proteome profiling data can outperform transcriptome profiling data for coexpression based gene function prediction has not been systematically investigated. Here, we address this question by constructing and analyzing mRNA and protein coexpression networks for three cancer types with matched mRNA and protein profiling data from The Cancer Genome Atlas (TCGA) and the Clinical Proteomic Tumor Analysis Consortium (CPTAC). Our analyses revealed a marked difference in wiring between the mRNA and protein coexpression networks. Whereas protein coexpression was driven primarily by functional similarity between coexpressed genes, mRNA coexpression was driven by both cofunction and chromosomal colocalization of the genes. Functionally coherent mRNA modules were more likely to have their edges preserved in corresponding protein networks than functionally incoherent mRNA modules. Proteomic data strengthened the link between gene expression and function for at least 75% of Gene Ontology (GO) biological processes and 90% of KEGG pathways. A web application Gene2Net (http://cptac.gene2net.org) developed based on the three protein coexpression networks revealed novel gene-function relationships, such as linking ERBB2 (HER2) to lipid biosynthetic process in breast cancer, identifying PLG as a new gene involved in complement activation, and identifying AEBP1 as a new epithelial-mesenchymal transition (EMT) marker. Our results demonstrate that proteome profiling outperforms transcriptome profiling for coexpression based gene function prediction. Proteomics should be integrated if not preferred in gene function and human disease studies.
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Affiliation(s)
- Jing Wang
- From the ‡Department of Biomedical Informatics, Vanderbilt University Medical Center, Nashville, Tennessee 37232.,§Lester and Sue Smith Breast Center, Baylor College of Medicine, Houston, Texas 77030.,¶Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030
| | - Zihao Ma
- From the ‡Department of Biomedical Informatics, Vanderbilt University Medical Center, Nashville, Tennessee 37232
| | - Steven A Carr
- ‖Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142
| | - Philipp Mertins
- ‖Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142
| | - Hui Zhang
- **Department of Pathology, Johns Hopkins Medical Institutions, Baltimore, Maryland 21205
| | - Zhen Zhang
- **Department of Pathology, Johns Hopkins Medical Institutions, Baltimore, Maryland 21205
| | - Daniel W Chan
- **Department of Pathology, Johns Hopkins Medical Institutions, Baltimore, Maryland 21205
| | - Matthew J C Ellis
- §Lester and Sue Smith Breast Center, Baylor College of Medicine, Houston, Texas 77030.,‡‡Department of Medicine, Baylor College of Medicine, Houston, Texas 77030
| | - R Reid Townsend
- §§Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Richard D Smith
- ¶¶Biological Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352
| | - Jason E McDermott
- ¶¶Biological Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352
| | - Xian Chen
- ‖‖University of North Carolina at Chapel Hill, 130 Mason Farm Road, Chapel Hill, North Carolina 27599
| | - Amanda G Paulovich
- Clinical Research Division, Fred Hutchinson Cancer Research Center, 1100 Eastlake Avenue East, Seattle, Washington 98109
| | - Emily S Boja
- Office of Cancer Clinical Proteomics Research, National Cancer Institute, Bethesda, Maryland 20892
| | - Mehdi Mesri
- Office of Cancer Clinical Proteomics Research, National Cancer Institute, Bethesda, Maryland 20892
| | - Christopher R Kinsinger
- Office of Cancer Clinical Proteomics Research, National Cancer Institute, Bethesda, Maryland 20892
| | - Henry Rodriguez
- Office of Cancer Clinical Proteomics Research, National Cancer Institute, Bethesda, Maryland 20892
| | - Karin D Rodland
- ¶¶Biological Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352
| | - Daniel C Liebler
- Department of Biochemistry, Vanderbilt University, Nashville, Tennessee 37232.,Jim Ayers Institute for Precancer Detection and Diagnosis, Vanderbilt-Ingram Cancer Center, Nashville, Tennessee 37232
| | - Bing Zhang
- From the ‡Department of Biomedical Informatics, Vanderbilt University Medical Center, Nashville, Tennessee 37232; .,§Lester and Sue Smith Breast Center, Baylor College of Medicine, Houston, Texas 77030.,¶Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030
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36
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Fang Y, Wang L, Wang X, You Q, Pan X, Xiao J, Wang XE, Wu Y, Su Z, Zhang W. Histone modifications facilitate the coexpression of bidirectional promoters in rice. BMC Genomics 2016; 17:768. [PMID: 27716056 PMCID: PMC5045660 DOI: 10.1186/s12864-016-3125-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Accepted: 09/26/2016] [Indexed: 12/27/2022] Open
Abstract
Background Bidirectional gene pairs are highly abundant and mostly co-regulated in eukaryotic genomes. The structural features of bidirectional promoters (BDPs) have been well studied in yeast, humans and plants. However, the underlying mechanisms responsible for the coexpression of BDPs remain understudied, especially in plants. Results Here, we characterized chromatin features associated with rice BDPs. Several unique chromatin features were present in rice BDPs but were missing from unidirectional promoters (UDPs), including overrepresented active histone marks, canonical nucleosomes and underrepresented H3K27me3. In particular, overrepresented active marks (H3K4ac, H4K12ac, H4K16ac, H3K4me2 and H3K36me3) were truly overrepresented in type I BDPs but not in the other two BDPs, based on a Kolmogorov-Smirnov test. Conclusions Our analyses indicate that active marks (H3K4ac, H4K12ac, H4K16ac, H3K4me3, H3K9ac and H3K27ac) may coordinate with repressive marks (H3K27me3 and H3K9me1/3) to build a unique chromatin structure that favors the coregulation of bidirectional gene pairs. Thus, our findings help to enhance the understanding of unique epigenetic mechanisms that regulate bidirectional gene pairs and may improve the manipulation of gene pairs for crop bioengineering. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-3125-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Yuan Fang
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Nanjing Agriculture University, Nanjing, Jiangsu, 210095, China
| | - Lei Wang
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Nanjing Agriculture University, Nanjing, Jiangsu, 210095, China
| | - Ximeng Wang
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Nanjing Agriculture University, Nanjing, Jiangsu, 210095, China
| | - Qi You
- State Key Laboratory of Plant Physiology and Biochemistry, CBS, China Agricultural University, Beijing, 100193, China
| | - Xiucai Pan
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Nanjing Agriculture University, Nanjing, Jiangsu, 210095, China
| | - Jin Xiao
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Nanjing Agriculture University, Nanjing, Jiangsu, 210095, China
| | - Xiu-E Wang
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Nanjing Agriculture University, Nanjing, Jiangsu, 210095, China
| | - Yufeng Wu
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Nanjing Agriculture University, Nanjing, Jiangsu, 210095, China
| | - Zhen Su
- State Key Laboratory of Plant Physiology and Biochemistry, CBS, China Agricultural University, Beijing, 100193, China.
| | - Wenli Zhang
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Nanjing Agriculture University, Nanjing, Jiangsu, 210095, China. .,JiangSu Collaborative Innovation Center for Modern Crop Production (JCIC-MCP), Nanjing Agriculture University, Nanjing, Jiangsu, 210095, China.
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37
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Ma X, Zhan G, Sleumer MC, Chen S, Liu W, Zhang MQ, Liu X. Analysis of C. elegans muscle transcriptome using trans-splicing-based RNA tagging (SRT). Nucleic Acids Res 2016; 44:e156. [PMID: 27557708 PMCID: PMC5137427 DOI: 10.1093/nar/gkw734] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Revised: 08/03/2016] [Accepted: 08/11/2016] [Indexed: 01/02/2023] Open
Abstract
Current approaches to profiling tissue-specific gene expression in C. elegans require delicate manipulation and are difficult under certain conditions, e.g. from dauer or aging worms. We have developed an easy and robust method for tissue-specific RNA-seq by taking advantage of the endogenous trans-splicing process. In this method, transgenic worms are generated in which a spliced leader (SL) RNA gene is fused with a sequence tag and driven by a tissue-specific promoter. Only in the tissue of interest, the tagged SL RNA gene is transcribed and then trans-spliced onto mRNAs. The tag allows enrichment and sequencing of mRNAs from that tissue only. As a proof of principle, we profiled the muscle transcriptome, which showed high coverage and efficient enrichment of muscle specific genes, with low background noise. To demonstrate the robustness of our method, we profiled muscle gene expression in dauer larvae and aging worms, revealing gene expression changes consistent with the physiology of these stages. The resulting muscle transcriptome also revealed 461 novel RNA transcripts, likely muscle-expressed long non-coding RNAs. In summary, the splicing-based RNA tagging (SRT) method provides a convenient and robust tool to profile trans-spliced genes and identify novel transcripts in a tissue-specific manner, with a low false positive rate.
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Affiliation(s)
- Xiaopeng Ma
- MOE Key Laboratory of Bioinformatics, Center for Synthetic and Systems Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China.,PTN (Peking University-Tsinghua University-National Institute of Biological Sciences) Joint Graduate Program, Beijing 100084, China
| | - Ge Zhan
- MOE Key Laboratory of Bioinformatics, Center for Synthetic and Systems Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Monica C Sleumer
- MOE Key Laboratory of Bioinformatics, Center for Synthetic and Systems Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Siyu Chen
- MOE Key Laboratory of Bioinformatics, Center for Synthetic and Systems Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Weihong Liu
- MOE Key Laboratory of Bioinformatics, Center for Synthetic and Systems Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Michael Q Zhang
- MOE Key Laboratory of Bioinformatics, Center for Synthetic and Systems Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China.,Departmental of Biological Sciences, Center for Systems Biology, The University of Texas at Dallas, TX 75080, USA.,Division of Bioinformatics, TNLIST, School of Information Sciences, Tsinghua University, Beijing 100084, China
| | - Xiao Liu
- MOE Key Laboratory of Bioinformatics, Center for Synthetic and Systems Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
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Marshall OJ, Southall TD, Cheetham SW, Brand AH. Cell-type-specific profiling of protein-DNA interactions without cell isolation using targeted DamID with next-generation sequencing. Nat Protoc 2016; 11:1586-98. [PMID: 27490632 DOI: 10.1038/nprot.2016.084] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
This protocol is an extension to: Nat. Protoc. 2, 1467-1478 (2007); doi:10.1038/nprot.2007.148; published online 7 June 2007The ability to profile transcription and chromatin binding in a cell-type-specific manner is a powerful aid to understanding cell-fate specification and cellular function in multicellular organisms. We recently developed targeted DamID (TaDa) to enable genome-wide, cell-type-specific profiling of DNA- and chromatin-binding proteins in vivo without cell isolation. As a protocol extension, this article describes substantial modifications to an existing protocol, and it offers additional applications. TaDa builds upon DamID, a technique for detecting genome-wide DNA-binding profiles of proteins, by coupling it with the GAL4 system in Drosophila to enable both temporal and spatial resolution. TaDa ensures that Dam-fusion proteins are expressed at very low levels, thus avoiding toxicity and potential artifacts from overexpression. The modifications to the core DamID technique presented here also increase the speed of sample processing and throughput, and adapt the method to next-generation sequencing technology. TaDa is robust, reproducible and highly sensitive. Compared with other methods for cell-type-specific profiling, the technique requires no cell-sorting, cross-linking or antisera, and binding profiles can be generated from as few as 10,000 total induced cells. By profiling the genome-wide binding of RNA polymerase II (Pol II), TaDa can also identify transcribed genes in a cell-type-specific manner. Here we describe a detailed protocol for carrying out TaDa experiments and preparing the material for next-generation sequencing. Although we developed TaDa in Drosophila, it should be easily adapted to other organisms with an inducible expression system. Once transgenic animals are obtained, the entire experimental procedure-from collecting tissue samples to generating sequencing libraries-can be accomplished within 5 d.
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Affiliation(s)
- Owen J Marshall
- The Gurdon Institute, University of Cambridge, Cambridge, UK.,Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, UK
| | - Tony D Southall
- The Gurdon Institute, University of Cambridge, Cambridge, UK.,Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, UK
| | - Seth W Cheetham
- The Gurdon Institute, University of Cambridge, Cambridge, UK.,Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, UK
| | - Andrea H Brand
- The Gurdon Institute, University of Cambridge, Cambridge, UK.,Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, UK
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Vogel MJ, Peric-Hupkes D, van Steensel B. Cell-type-specific profiling of protein-DNA interactions without cell isolation using targeted DamID with next-generation sequencing. Nat Protoc 2016; 2:1467-78. [PMID: 17545983 DOI: 10.1038/nprot.2007.148] [Citation(s) in RCA: 229] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
This protocol is an extension to: Nat. Protoc. 2, 1467-1478 (2007); doi:10.1038/nprot.2007.148; published online 7 June 2007The ability to profile transcription and chromatin binding in a cell-type-specific manner is a powerful aid to understanding cell-fate specification and cellular function in multicellular organisms. We recently developed targeted DamID (TaDa) to enable genome-wide, cell-type-specific profiling of DNA- and chromatin-binding proteins in vivo without cell isolation. As a protocol extension, this article describes substantial modifications to an existing protocol, and it offers additional applications. TaDa builds upon DamID, a technique for detecting genome-wide DNA-binding profiles of proteins, by coupling it with the GAL4 system in Drosophila to enable both temporal and spatial resolution. TaDa ensures that Dam-fusion proteins are expressed at very low levels, thus avoiding toxicity and potential artifacts from overexpression. The modifications to the core DamID technique presented here also increase the speed of sample processing and throughput, and adapt the method to next-generation sequencing technology. TaDa is robust, reproducible and highly sensitive. Compared with other methods for cell-type-specific profiling, the technique requires no cell-sorting, cross-linking or antisera, and binding profiles can be generated from as few as 10,000 total induced cells. By profiling the genome-wide binding of RNA polymerase II (Pol II), TaDa can also identify transcribed genes in a cell-type-specific manner. Here we describe a detailed protocol for carrying out TaDa experiments and preparing the material for next-generation sequencing. Although we developed TaDa in Drosophila, it should be easily adapted to other organisms with an inducible expression system. Once transgenic animals are obtained, the entire experimental procedure-from collecting tissue samples to generating sequencing libraries-can be accomplished within 5 d.
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Affiliation(s)
- Maartje J Vogel
- Division of Molecular Biology, Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
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40
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Mann FG, Van Nostrand EL, Friedland AE, Liu X, Kim SK. Deactivation of the GATA Transcription Factor ELT-2 Is a Major Driver of Normal Aging in C. elegans. PLoS Genet 2016; 12:e1005956. [PMID: 27070429 PMCID: PMC4829211 DOI: 10.1371/journal.pgen.1005956] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 03/04/2016] [Indexed: 02/07/2023] Open
Abstract
To understand the molecular processes underlying aging, we screened modENCODE ChIP-seq data to identify transcription factors that bind to age-regulated genes in C. elegans. The most significant hit was the GATA transcription factor encoded by elt-2, which is responsible for inducing expression of intestinal genes during embryogenesis. Expression of ELT-2 decreases during aging, beginning in middle age. We identified genes regulated by ELT-2 in the intestine during embryogenesis, and then showed that these developmental genes markedly decrease in expression as worms grow old. Overexpression of elt-2 extends lifespan and slows the rate of gene expression changes that occur during normal aging. Thus, our results identify the developmental regulator ELT-2 as a major driver of normal aging in C. elegans.
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Affiliation(s)
- Frederick G. Mann
- Departments of Genetics and Developmental Biology, Stanford University Medical Center, Stanford, California, United States of America
| | - Eric L. Van Nostrand
- Department of Cellular and Molecular Medicine, Institute of Genomic Medicine, University of California, San Diego, La Jolla, California, United States of America
| | - Ari E. Friedland
- Editas Medicine, Cambridge, Massachusetts, United States of America
| | - Xiao Liu
- School of Life Sciences, Tsinghua University, Beijing, China
| | - Stuart K. Kim
- Departments of Genetics and Developmental Biology, Stanford University Medical Center, Stanford, California, United States of America
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Nesterovitch AB, Arbieva Z, Toth DM, Tharp MD, Glant TT. A differential gene expression study: Ptpn6 (SHP-1)-insufficiency leads to neutrophilic dermatosis-like disease (NDLD) in mice. J Dermatol Sci 2016; 83:17-25. [PMID: 27020408 DOI: 10.1016/j.jdermsci.2016.03.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Revised: 01/25/2016] [Accepted: 03/04/2016] [Indexed: 12/11/2022]
Abstract
BACKGROUND Irradiated syngeneic wild-type mice developed the same neutrophilic dermatosis-like disease (NDLD) after adoptive transfer of bone marrow cells from Ptpn6(meb2/meb2) mutant mice. OBJECTIVE To analyze differentially expressed genes in the bone marrow of mice with NDLD to gain insight into the role of Ptpn6 in myelopoietic bone marrow pathology, and the mechanisms by which Ptpn6 insufficiency in the hematopoietic cells can lead to the development of skin lesions. METHODS As Ptpn6 is involved in a myriad of signaling pathways, we used a global approach with microarray technology for the first time to characterize changes in the bone marrow and skin of motheaten-type mice. RESULTS A total number of 1,511 probe sets in the bone marrow showed at least two-fold changes with FDR <0.05, of which 256 probe sets had over four-fold changes. A group of 63 genes in the bone marrow of NDLD mice had more than a 4-fold change with FDR <0.0001. From 503 genes encoding proteins with ITIM motif that binds to Ptpn6, 109 were up-regulated and 83 were down-regulated. We found that genes encoding hematopoietic receptors, neutrophil chemoattractants, Toll-like receptors (Tlr1, Tlr2 and Tlr4) and C-type lectin innate immunity receptors (Clec4e, Clec4d, Clec4n, Clec4a2 and Clec4a3) were significantly up-regulated in both NDLD bone marrow and skin. The Il1b gene was also significantly overexpressed in skin samples, confirming the importance of the IL-1/TLR pathway in the development of early skin inflammation in NDLD mice. CONCLUSION Our results suggest that innate immunity genes play a major role in development of neutrophilic dermatosis-like disease in mice.
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Affiliation(s)
| | - Zarema Arbieva
- Core Genomics Facility, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Daniel M Toth
- Department of Orthopedic Surgery (Section of Molecular Medicine), Biochemistry and Internal Medicine (Section of Rheumatology), Rush University Medical Center, Chicago, IL 60612, USA
| | - Michael D Tharp
- Department of Dermatology, Rush University Medical Center, Chicago, IL 60612, USA
| | - Tibor T Glant
- Department of Orthopedic Surgery (Section of Molecular Medicine), Biochemistry and Internal Medicine (Section of Rheumatology), Rush University Medical Center, Chicago, IL 60612, USA
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Topologically associated domains enriched for lineage-specific genes reveal expression-dependent nuclear topologies during myogenesis. Proc Natl Acad Sci U S A 2016; 113:E1691-700. [PMID: 26957603 DOI: 10.1073/pnas.1521826113] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The linear distribution of genes across chromosomes and the spatial localization of genes within the nucleus are related to their transcriptional regulation. The mechanistic consequences of linear gene order, and how it may relate to the functional output of genome organization, remain to be fully resolved, however. Here we tested the relationship between linear and 3D organization of gene regulation during myogenesis. Our analysis has identified a subset of topologically associated domains (TADs) that are significantly enriched for muscle-specific genes. These lineage-enriched TADs demonstrate an expression-dependent pattern of nuclear organization that influences the positioning of adjacent nonenriched TADs. Therefore, lineage-enriched TADs inform cell-specific genome organization during myogenesis. The reduction of allelic spatial distance of one of these domains, which contains Myogenin, correlates with reduced transcriptional variability, identifying a potential role for lineage-specific nuclear topology. Using a fusion-based strategy to decouple mitosis and myotube formation, we demonstrate that the cell-specific topology of syncytial nuclei is dependent on cell division. We propose that the effects of linear and spatial organization of gene loci on gene regulation are linked through TAD architecture, and that mitosis is critical for establishing nuclear topologies during cellular differentiation.
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Burdick J, Walton T, Preston E, Zacharias A, Raj A, Murray JI. Overlapping cell population expression profiling and regulatory inference in C. elegans. BMC Genomics 2016; 17:159. [PMID: 26926147 PMCID: PMC4772325 DOI: 10.1186/s12864-016-2482-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Accepted: 02/17/2016] [Indexed: 12/30/2022] Open
Abstract
Background Understanding gene expression across the diverse metazoan cell types during development is critical to understanding their function and regulation. However, most cell types have not been assayed for expression genome-wide. Results We applied a novel approach we term “Profiling of Overlapping Populations of cells (POP-Seq)” to assay differential expression across all embryonic cells in the nematode Caenorhabditis elegans. In this approach, we use RNA-seq to define the transcriptome of diverse partially overlapping FACS-sorted cell populations. This identified thousands of transcripts differentially expressed across embryonic cells. Hierarchical clustering analysis identified over 100 sets of coexpressed genes corresponding to distinct patterns of cell type specific expression. We identified thousands of candidate regulators of these clusters based on enrichment of transcription factor motifs and experimentally determined binding sites. Conclusions Our analysis provides new insight into embryonic gene regulation, and provides a resource for improving our knowledge of tissue-specific expression and its regulation throughout C. elegans development. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-2482-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Joshua Burdick
- Department of Genetics, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
| | - Travis Walton
- Department of Genetics, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
| | - Elicia Preston
- Department of Genetics, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
| | - Amanda Zacharias
- Department of Genetics, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
| | - Arjun Raj
- Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
| | - John Isaac Murray
- Department of Genetics, University of Pennsylvania, Philadelphia, Pennsylvania, USA. .,Department of Genetics, Perelman School of Medicine, University of Pennsylvania, 437A Clinical Research Building, 415 Curie Boulevard, Philadelphia, PA, 19104-6145, USA.
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Berber S, Wood M, Llamosas E, Thaivalappil P, Lee K, Liao BM, Chew YL, Rhodes A, Yucel D, Crossley M, Nicholas HR. Homeodomain-Interacting Protein Kinase (HPK-1) regulates stress responses and ageing in C. elegans. Sci Rep 2016; 6:19582. [PMID: 26791749 PMCID: PMC4726358 DOI: 10.1038/srep19582] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Accepted: 12/15/2015] [Indexed: 11/22/2022] Open
Abstract
Proteins of the Homeodomain-Interacting Protein Kinase (HIPK) family regulate an array of processes in mammalian systems, such as the DNA damage response, cellular proliferation and apoptosis. The nematode Caenorhabditis elegans has a single HIPK homologue called HPK-1. Previous studies have implicated HPK-1 in longevity control and suggested that this protein may be regulated in a stress-dependent manner. Here we set out to expand these observations by investigating the role of HPK-1 in longevity and in the response to heat and oxidative stress. We find that levels of HPK-1 are regulated by heat stress, and that HPK-1 contributes to survival following heat or oxidative stress. Additionally, we show that HPK-1 is required for normal longevity, with loss of HPK-1 function leading to a faster decline of physiological processes that reflect premature ageing. Through microarray analysis, we have found that HPK-1-regulated genes include those encoding proteins that serve important functions in stress responses such as Phase I and Phase II detoxification enzymes. Consistent with a role in longevity assurance, HPK-1 also regulates the expression of age-regulated genes. Lastly, we show that HPK-1 functions in the same pathway as DAF-16 to regulate longevity and reveal a new role for HPK-1 in development.
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Affiliation(s)
- Slavica Berber
- School of Molecular Bioscience, University of Sydney, Sydney, Australia
| | - Mallory Wood
- School of Molecular Bioscience, University of Sydney, Sydney, Australia
| | - Estelle Llamosas
- School of Molecular Bioscience, University of Sydney, Sydney, Australia
| | | | - Karen Lee
- School of Molecular Bioscience, University of Sydney, Sydney, Australia
| | - Bing Mana Liao
- School of Molecular Bioscience, University of Sydney, Sydney, Australia
| | - Yee Lian Chew
- School of Molecular Bioscience, University of Sydney, Sydney, Australia
| | - Aaron Rhodes
- School of Molecular Bioscience, University of Sydney, Sydney, Australia
| | - Duygu Yucel
- School of Molecular Bioscience, University of Sydney, Sydney, Australia
| | - Merlin Crossley
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Kensington, Australia
| | - Hannah R Nicholas
- School of Molecular Bioscience, University of Sydney, Sydney, Australia
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Gracida X, Norris AD, Calarco JA. Regulation of Tissue-Specific Alternative Splicing: C. elegans as a Model System. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 907:229-61. [DOI: 10.1007/978-3-319-29073-7_10] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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46
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Three-dimensional Genomic Organization of Genes’ Function in Eukaryotes. Evol Biol 2016. [DOI: 10.1007/978-3-319-41324-2_14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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47
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Druzhinina IS, Kopchinskiy AG, Kubicek EM, Kubicek CP. A complete annotation of the chromosomes of the cellulase producer Trichoderma reesei provides insights in gene clusters, their expression and reveals genes required for fitness. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:75. [PMID: 27030800 PMCID: PMC4812632 DOI: 10.1186/s13068-016-0488-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 03/15/2016] [Indexed: 05/15/2023]
Abstract
BACKGROUND Investigations on a few eukaryotic model organisms showed that many genes are non-randomly distributed on chromosomes. In addition, chromosome ends frequently possess genes that are important for the fitness of the organisms. Trichoderma reesei is an industrial producer of enzymes for food, feed and biorefinery production. Its seven chromosomes have recently been assembled, thus making an investigation of its chromosome architecture possible. RESULTS We manually annotated and mapped 9194 ORFs on their respective chromosomes and investigated the clustering of the major gene categories and of genes encoding carbohydrate-active enzymes (CAZymes), and the relationship between clustering and expression. Genes responsible for RNA processing and modification, amino acid metabolism, transcription, translation and ribosomal structure and biogenesis indeed showed loose clustering, but this had no impact on their expression. A third of the genes encoding CAZymes also occurred in loose clusters that also contained a high number of genes encoding small secreted cysteine-rich proteins. Five CAZyme clusters were located less than 50 kb apart from the chromosome ends. These genes exhibited the lowest basal (but not induced) expression level, which correlated with an enrichment of H3K9 methylation in the terminal 50 kb areas indicating gene silencing. No differences were found in the expression of CAZyme genes present in other parts of the chromosomes. The putative subtelomeric areas were also enriched in genes encoding secreted proteases, amino acid permeases, enzyme clusters for polyketide synthases (PKS)-non-ribosomal peptide synthase (NRPS) fusion proteins (PKS-NRPS) and proteins involved in iron scavenging. They were strongly upregulated during conidiation and interaction with other fungi. CONCLUSIONS Our findings suggest that gene clustering on the T. reesei chromosomes occurs but generally has no impact on their expression. CAZyme genes, located in subtelomers, however, exhibited a much lower basal expression level. The gene inventory of the subtelomers suggests a major role of competition for nitrogen and iron supported by antibiosis for the fitness of T. reesei. The availability of fully annotated chromosomes will facilitate the use of genetic crossings in identifying still unknown genes responsible for specific traits of T. reesei.
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Affiliation(s)
- Irina S. Druzhinina
- />Research Area Biotechnology and Microbiology, Institute of Chemical Engineering, TU Wien, 1060 Vienna, Austria
| | - Alexey G. Kopchinskiy
- />Research Area Biotechnology and Microbiology, Institute of Chemical Engineering, TU Wien, 1060 Vienna, Austria
| | - Eva M. Kubicek
- />Research Area Biotechnology and Microbiology, Institute of Chemical Engineering, TU Wien, 1060 Vienna, Austria
- />Steinschötelgasse 7, 1100 Vienna, Austria
| | - Christian P. Kubicek
- />Research Area Biotechnology and Microbiology, Institute of Chemical Engineering, TU Wien, 1060 Vienna, Austria
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Hirbo J, Eidem H, Rokas A, Abbot P. Integrating Diverse Types of Genomic Data to Identify Genes that Underlie Adverse Pregnancy Phenotypes. PLoS One 2015; 10:e0144155. [PMID: 26641094 PMCID: PMC4671692 DOI: 10.1371/journal.pone.0144155] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Accepted: 11/14/2015] [Indexed: 11/18/2022] Open
Abstract
Progress in understanding complex genetic diseases has been bolstered by synthetic approaches that overlay diverse data types and analyses to identify functionally important genes. Pre-term birth (PTB), a major complication of pregnancy, is a leading cause of infant mortality worldwide. A major obstacle in addressing PTB is that the mechanisms controlling parturition and birth timing remain poorly understood. Integrative approaches that overlay datasets derived from comparative genomics with function-derived ones have potential to advance our understanding of the genetics of birth timing, and thus provide insights into the genes that may contribute to PTB. We intersected data from fast evolving coding and non-coding gene regions in the human and primate lineage with data from genes expressed in the placenta, from genes that show enriched expression only in the placenta, as well as from genes that are differentially expressed in four distinct PTB clinical subtypes. A large fraction of genes that are expressed in placenta, and differentially expressed in PTB clinical subtypes (23–34%) are fast evolving, and are associated with functions that include adhesion neurodevelopmental and immune processes. Functional categories of genes that express fast evolution in coding regions differ from those linked to fast evolution in non-coding regions. Finally, there is a surprising lack of overlap between fast evolving genes that are differentially expressed in four PTB clinical subtypes. Integrative approaches, especially those that incorporate evolutionary perspectives, can be successful in identifying potential genetic contributions to complex genetic diseases, such as PTB.
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Affiliation(s)
- Jibril Hirbo
- Department of Biological Sciences, Vanderbilt University, Box 35164 Station B, Nashville, TN, 37235–1634, United States of America
| | - Haley Eidem
- Department of Biological Sciences, Vanderbilt University, Box 35164 Station B, Nashville, TN, 37235–1634, United States of America
| | - Antonis Rokas
- Department of Biological Sciences, Vanderbilt University, Box 35164 Station B, Nashville, TN, 37235–1634, United States of America
| | - Patrick Abbot
- Department of Biological Sciences, Vanderbilt University, Box 35164 Station B, Nashville, TN, 37235–1634, United States of America
- * E-mail:
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Dutta D, Buchon N, Xiang J, Edgar BA. Regional Cell Specific RNA Expression Profiling of FACS Isolated Drosophila Intestinal Cell Populations. ACTA ACUST UNITED AC 2015; 34:2F.2.1-2F.2.14. [PMID: 26237570 DOI: 10.1002/9780470151808.sc02f02s34] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The adult Drosophila midgut is built of five distinct cell types, including stem cells, enteroblasts, enterocytes, enteroendocrine cells, and visceral muscles, and is divided into five major regions (R1 to R5), which are morphologically and functionally distinct from each other. This unit describes a protocol for the isolation of Drosophila intestinal cell populations for the purpose of cell type-specific transcriptome profiling from the five different regions. A method to select a cell type of interest labeled with green or yellow fluorescent protein (GFP, YFP) by making use of the GAL4-UAS bipartite system and fluorescent-activated cell sorting (FACS) is presented. Total RNA is isolated from the sorted cells of each region, and linear RNA amplification is used to obtain sufficient amounts of high-quality RNA for analysis by microarray, RT-PCR, or RNA sequencing. This method will be useful for quantitative transcriptome comparison across intestinal cell types in the different regions under normal and various experimental conditions.
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Affiliation(s)
- Devanjali Dutta
- DKFZ-ZMBH Alliance, University of Heidelberg, Heidelberg, Germany
| | - Nicolas Buchon
- Department of Entomology, Cornell University, Ithaca, New York
| | - Jinyi Xiang
- DKFZ-ZMBH Alliance, University of Heidelberg, Heidelberg, Germany
| | - Bruce A Edgar
- DKFZ-ZMBH Alliance, University of Heidelberg, Heidelberg, Germany
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50
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McClure CD, Southall TD. Getting Down to Specifics: Profiling Gene Expression and Protein-DNA Interactions in a Cell Type-Specific Manner. ADVANCES IN GENETICS 2015; 91:103-151. [PMID: 26410031 PMCID: PMC4604662 DOI: 10.1016/bs.adgen.2015.06.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The majority of multicellular organisms are comprised of an extraordinary range of cell types, with different properties and gene expression profiles. Understanding what makes each cell type unique and how their individual characteristics are attributed are key questions for both developmental and neurobiologists alike. The brain is an excellent example of the cellular diversity expressed in the majority of eukaryotes. The mouse brain comprises of approximately 75 million neurons varying in morphology, electrophysiology, and preferences for synaptic partners. A powerful process in beginning to pick apart the mechanisms that specify individual characteristics of the cell, as well as their fate, is to profile gene expression patterns, chromatin states, and transcriptional networks in a cell type-specific manner, i.e., only profiling the cells of interest in a particular tissue. Depending on the organism, the questions being investigated, and the material available, certain cell type-specific profiling methods are more suitable than others. This chapter reviews the approaches presently available for selecting and isolating specific cell types and evaluates their key features.
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Affiliation(s)
- Colin D. McClure
- Department of Life Sciences, Imperial College London, Sir Ernst Chain Building, South Kensington Campus, London SW7 2AZ, United Kingdom
| | - Tony D. Southall
- Department of Life Sciences, Imperial College London, Sir Ernst Chain Building, South Kensington Campus, London SW7 2AZ, United Kingdom
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