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Korhonen PK, Wang T, Young ND, Byrne JJ, Campos TL, Chang BC, Taki AC, Gasser RB. Analysis of Haemonchus embryos at single cell resolution identifies two eukaryotic elongation factors as intervention target candidates. Comput Struct Biotechnol J 2024; 23:1026-1035. [PMID: 38435301 PMCID: PMC10907403 DOI: 10.1016/j.csbj.2024.01.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2023] [Revised: 01/14/2024] [Accepted: 01/15/2024] [Indexed: 03/05/2024] Open
Abstract
Advances in single cell technologies are allowing investigations of a wide range of biological processes and pathways in animals, such as the multicellular model organism Caenorhabditis elegans - a free-living nematode. However, there has been limited application of such technology to related parasitic nematodes which cause major diseases of humans and animals worldwide. With no vaccines against the vast majority of parasitic nematodes and treatment failures due to drug resistance or inefficacy, new intervention targets are urgently needed, preferably informed by a deep understanding of these nematodes' cellular and molecular biology - which is presently lacking for most worms. Here, we created the first single cell atlas for an early developmental stage of Haemonchus contortus - a highly pathogenic, C. elegans-related parasitic nematode. We obtained and curated RNA sequence (snRNA-seq) data from single nuclei from embryonating eggs of H. contortus (150,000 droplets), and selected high-quality transcriptomic data for > 14,000 single nuclei for analysis, and identified 19 distinct clusters of cells. Guided by comparative analyses with C. elegans, we were able to reproducibly assign seven cell clusters to body wall muscle, hypodermis, neuronal, intestinal or seam cells, and identified eight genes that were transcribed in all cell clusters/types, three of which were inferred to be essential in H. contortus. Two of these genes (i.e. Hc-eef-1A and Hc-eef1G), coding for eukaryotic elongation factors (called Hc-eEF1A and Hc-eEF1G), were also demonstrated to be transcribed and expressed in all key developmental stages of H. contortus. Together with these findings, sequence- and structure-based comparative analyses indicated the potential of Hc-eEF1A and/or Hc-eEF1G as intervention targets within the protein biosynthesis machinery of H. contortus. Future work will focus on single cell studies of all key developmental stages and tissues of H. contortus, and on evaluating the suitability of the two elongation factor proteins as drug targets in H. contortus and related nematodes, with a view to finding new nematocidal drug candidates.
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Affiliation(s)
- Pasi K. Korhonen
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Tao Wang
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Neil D. Young
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Joseph J. Byrne
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Tulio L. Campos
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Bill C.H. Chang
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Aya C. Taki
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Robin B. Gasser
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, Victoria 3010, Australia
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2
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Barker E, Morgan A, Barclay JW. Tissue distribution of cysteine string protein/DNAJC5 in C. elegans analysed by CRISPR/Cas9-mediated tagging of endogenous DNJ-14. Cell Tissue Res 2024; 396:41-55. [PMID: 38403745 PMCID: PMC10997724 DOI: 10.1007/s00441-024-03875-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Accepted: 02/06/2024] [Indexed: 02/27/2024]
Abstract
Cysteine string protein (CSP) is a member of the DnaJ/Hsp40 family of molecular chaperones. CSP is enriched in neurons, where it mainly localises to synaptic vesicles. Mutations in CSP-encoding genes in flies, worms, mice and humans result in neuronal dysfunction, neurodegeneration and reduced lifespan. Most attention has therefore focused on CSP's neuronal functions, although CSP is also expressed in non-neuronal cells. Here, we used genome editing to fluorescently tag the Caenorhabditis elegans CSP orthologue, dnj-14, to identify which tissues preferentially express CSP and hence may contribute to the observed mutant phenotypes. Replacement of dnj-14 with wrmScarlet caused a strong chemotaxis defect, as seen with other dnj-14 null mutants. In contrast, inserting the reporter in-frame to create a DNJ-14-wrmScarlet fusion protein had no effect on chemotaxis, indicating that C-terminal tagging does not impair DNJ-14 function. WrmScarlet fluorescence appeared most obvious in the intestine, head/pharynx, spermathecae and vulva/uterus in the reporter strains, suggesting that DNJ-14 is preferentially expressed in these tissues. Crossing the DNJ-14-wrmScarlet strain with GFP marker strains confirmed the intestinal and pharyngeal expression, but only a partial overlap with neuronal GFP was observed. DNJ-14-wrmScarlet fluorescence in the intestine was increased in response to starvation, which may be relevant to mammalian CSPα's role in microautophagy. DNJ-14's enrichment in worm reproductive tissues (spermathecae and vulva/uterus) parallels the testis-specific expression of CSPβ and CSPγ isoforms in mammals. Furthermore, CSPα messenger RNA is highly expressed in the human proximal digestive tract, suggesting that CSP may have a conserved, but overlooked, function within the gastrointestinal system.
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Affiliation(s)
- Eleanor Barker
- Department of Molecular Physiology & Cell Signalling, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Crown St, Liverpool, L69 3BX, UK
- Current address: Division of Diabetes, Endocrinology and Gastroenterology, Faculty of Biology, Medicine and Health, The University of Manchester, Oxford Road, Manchester, M13 9PT, UK
| | - Alan Morgan
- Department of Molecular Physiology & Cell Signalling, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Crown St, Liverpool, L69 3BX, UK.
| | - Jeff W Barclay
- Department of Molecular Physiology & Cell Signalling, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Crown St, Liverpool, L69 3BX, UK.
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3
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Yashar WM, Estabrook J, Holly HD, Somers J, Nikolova O, Babur Ö, Braun TP, Demir E. Predicting transcription factor activity using prior biological information. iScience 2024; 27:109124. [PMID: 38455978 PMCID: PMC10918219 DOI: 10.1016/j.isci.2024.109124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 10/20/2023] [Accepted: 01/31/2024] [Indexed: 03/09/2024] Open
Abstract
Dysregulation of normal transcription factor activity is a common driver of disease. Therefore, the detection of aberrant transcription factor activity is important to understand disease pathogenesis. We have developed Priori, a method to predict transcription factor activity from RNA sequencing data. Priori has two key advantages over existing methods. First, Priori utilizes literature-supported regulatory information to identify transcription factor-target gene relationships. It then applies linear models to determine the impact of transcription factor regulation on the expression of its target genes. Second, results from a third-party benchmarking pipeline reveals that Priori detects aberrant activity from 124 single-gene perturbation experiments with higher sensitivity and specificity than 11 other methods. We applied Priori and other top-performing methods to predict transcription factor activity from two large primary patient datasets. Our work demonstrates that Priori uniquely discovered significant determinants of survival in breast cancer and identified mediators of drug response in leukemia.
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Affiliation(s)
- William M. Yashar
- Knight Cancer Institute, Oregon Health & Science University, Portland, OR 97239, USA
- Division of Oncologic Sciences, Department of Medicine, Oregon Health & Science University, Portland, OR 97239, USA
- Department of Biomedical Engineering, Oregon Health & Science University, Portland, OR 97239, USA
| | - Joseph Estabrook
- Knight Cancer Institute, Oregon Health & Science University, Portland, OR 97239, USA
- Department of Molecular and Medical Genetics, Oregon Health and Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA
- Cancer Early Detection Advanced Research Center, Oregon Health & Science University, Portland, OR 97239, USA
| | - Hannah D. Holly
- Department of Molecular and Medical Genetics, Oregon Health and Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA
- Cancer Early Detection Advanced Research Center, Oregon Health & Science University, Portland, OR 97239, USA
| | - Julia Somers
- Department of Molecular and Medical Genetics, Oregon Health and Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA
- Cancer Early Detection Advanced Research Center, Oregon Health & Science University, Portland, OR 97239, USA
| | - Olga Nikolova
- Knight Cancer Institute, Oregon Health & Science University, Portland, OR 97239, USA
- Division of Oncologic Sciences, Department of Medicine, Oregon Health & Science University, Portland, OR 97239, USA
- Department of Biomedical Engineering, Oregon Health & Science University, Portland, OR 97239, USA
| | - Özgün Babur
- Computer Science Department, University of Massachusetts, Boston, MA 02125, USA
| | - Theodore P. Braun
- Knight Cancer Institute, Oregon Health & Science University, Portland, OR 97239, USA
- Division of Oncologic Sciences, Department of Medicine, Oregon Health & Science University, Portland, OR 97239, USA
- Division of Hematology & Medical Oncology, Department of Medicine, Oregon Health & Science University, Portland, OR 97239, USA
| | - Emek Demir
- Knight Cancer Institute, Oregon Health & Science University, Portland, OR 97239, USA
- Division of Oncologic Sciences, Department of Medicine, Oregon Health & Science University, Portland, OR 97239, USA
- Department of Molecular and Medical Genetics, Oregon Health and Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA
- Pacific Northwest National Laboratories, Richland, WA 99354, USA
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4
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Nasrallah MA, Peterson ND, Szumel ES, Liu P, Page AL, Tse SY, Wani KA, Tocheny CE, Pukkila-Worley R. Transcriptional suppression of sphingolipid catabolism controls pathogen resistance in C. elegans. PLoS Pathog 2023; 19:e1011730. [PMID: 37906605 PMCID: PMC10637724 DOI: 10.1371/journal.ppat.1011730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 11/10/2023] [Accepted: 10/01/2023] [Indexed: 11/02/2023] Open
Abstract
Sphingolipids are required for diverse biological functions and are degraded by specific catabolic enzymes. However, the mechanisms that regulate sphingolipid catabolism are not known. Here we characterize a transcriptional axis that regulates sphingolipid breakdown to control resistance against bacterial infection. From an RNAi screen for transcriptional regulators of pathogen resistance in the nematode C. elegans, we identified the nuclear hormone receptor nhr-66, a ligand-gated transcription factor homologous to human hepatocyte nuclear factor 4. Tandem chromatin immunoprecipitation-sequencing and RNA sequencing experiments revealed that NHR-66 is a transcriptional repressor, which directly targets sphingolipid catabolism genes. Transcriptional de-repression of two sphingolipid catabolic enzymes in nhr-66 loss-of-function mutants drives the breakdown of sphingolipids, which enhances host susceptibility to infection with the bacterial pathogen Pseudomonas aeruginosa. These data define transcriptional control of sphingolipid catabolism in the regulation of cellular sphingolipids, a process that is necessary for pathogen resistance.
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Affiliation(s)
- Mohamad A. Nasrallah
- Program in Innate Immunity, Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Chan Medical School, Worcester, Massachusetts, United States of America
| | - Nicholas D. Peterson
- Program in Innate Immunity, Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Chan Medical School, Worcester, Massachusetts, United States of America
| | - Elizabeth S. Szumel
- Program in Innate Immunity, Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Chan Medical School, Worcester, Massachusetts, United States of America
| | - Pengpeng Liu
- Department of Molecular, Cell and Cancer Biology, University of Massachusetts Chan Medical School, Worcester, Massachusetts, United States of America
| | - Amanda L. Page
- Program in Innate Immunity, Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Chan Medical School, Worcester, Massachusetts, United States of America
| | - Samantha Y. Tse
- Program in Innate Immunity, Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Chan Medical School, Worcester, Massachusetts, United States of America
| | - Khursheed A. Wani
- Program in Innate Immunity, Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Chan Medical School, Worcester, Massachusetts, United States of America
| | - Claire E. Tocheny
- Program in Innate Immunity, Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Chan Medical School, Worcester, Massachusetts, United States of America
| | - Read Pukkila-Worley
- Program in Innate Immunity, Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Chan Medical School, Worcester, Massachusetts, United States of America
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5
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Peterson ND, Tse SY, Huang QJ, Wani KA, Schiffer CA, Pukkila-Worley R. Non-canonical pattern recognition of a pathogen-derived metabolite by a nuclear hormone receptor identifies virulent bacteria in C. elegans. Immunity 2023; 56:768-782.e9. [PMID: 36804958 PMCID: PMC10101930 DOI: 10.1016/j.immuni.2023.01.027] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 11/27/2022] [Accepted: 01/25/2023] [Indexed: 02/19/2023]
Abstract
Distinguishing infectious pathogens from harmless microorganisms is essential for animal health. The mechanisms used to identify infectious microbes are not fully understood, particularly in metazoan hosts that eat bacteria as their food source. Here, we characterized a non-canonical pattern-recognition system in Caenorhabditis elegans (C. elegans) that assesses the relative threat of virulent Pseudomonas aeruginosa (P. aeruginosa) to activate innate immunity. We discovered that the innate immune response in C. elegans was triggered by phenazine-1-carboxamide (PCN), a toxic metabolite produced by pathogenic strains of P. aeruginosa. We identified the nuclear hormone receptor NHR-86/HNF4 as the PCN sensor in C. elegans and validated that PCN bound to the ligand-binding domain of NHR-86/HNF4. Activation of NHR-86/HNF4 by PCN directly engaged a transcriptional program in intestinal epithelial cells that protected against P. aeruginosa. Thus, a bacterial metabolite is a pattern of pathogenesis surveilled by nematodes to identify a pathogen in its bacterial diet.
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Affiliation(s)
- Nicholas D Peterson
- Program in Innate Immunity, Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Samantha Y Tse
- Program in Innate Immunity, Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Qiuyu Judy Huang
- Department of Biochemistry and Molecular Biotechnology, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Khursheed A Wani
- Program in Innate Immunity, Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Celia A Schiffer
- Department of Biochemistry and Molecular Biotechnology, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Read Pukkila-Worley
- Program in Innate Immunity, Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA.
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6
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Nanda S, Jacques MA, Wang W, Myers CL, Yilmaz LS, Walhout AJ. Systems-level transcriptional regulation of Caenorhabditis elegans metabolism. Mol Syst Biol 2023; 19:e11443. [PMID: 36942755 PMCID: PMC10167481 DOI: 10.15252/msb.202211443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 03/03/2023] [Accepted: 03/07/2023] [Indexed: 03/23/2023] Open
Abstract
Metabolism is controlled to ensure organismal development and homeostasis. Several mechanisms regulate metabolism, including allosteric control and transcriptional regulation of metabolic enzymes and transporters. So far, metabolism regulation has mostly been described for individual genes and pathways, and the extent of transcriptional regulation of the entire metabolic network remains largely unknown. Here, we find that three-quarters of all metabolic genes are transcriptionally regulated in the nematode Caenorhabditis elegans. We find that many annotated metabolic pathways are coexpressed, and we use gene expression data and the iCEL1314 metabolic network model to define coregulated subpathways in an unbiased manner. Using a large gene expression compendium, we determine the conditions where subpathways exhibit strong coexpression. Finally, we develop "WormClust," a web application that enables a gene-by-gene query of genes to view their association with metabolic (sub)-pathways. Overall, this study sheds light on the ubiquity of transcriptional regulation of metabolism and provides a blueprint for similar studies in other organisms, including humans.
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Affiliation(s)
- Shivani Nanda
- Department of Systems Biology, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Marc-Antoine Jacques
- Department of Systems Biology, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Wen Wang
- Department of Computer Science and Engineering, University of Minnesota, Minneapolis, MN, USA
| | - Chad L Myers
- Department of Computer Science and Engineering, University of Minnesota, Minneapolis, MN, USA
| | - L Safak Yilmaz
- Department of Systems Biology, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Albertha Jm Walhout
- Department of Systems Biology, University of Massachusetts Chan Medical School, Worcester, MA, USA
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7
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Horowitz BB, Nanda S, Walhout AJ. A Transcriptional Cofactor Regulatory Network for the C. elegans Intestine. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.05.522920. [PMID: 36711629 PMCID: PMC9881946 DOI: 10.1101/2023.01.05.522920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Chromatin modifiers and transcriptional cofactors (collectively referred to as CFs) work with DNA-binding transcription factors (TFs) to regulate gene expression. In multicellular eukaryotes, distinct tissues each execute their own gene expression program for accurate differentiation and subsequent functionality. While the function of TFs in differential gene expression has been studied in detail in many systems, the contribution of CFs has remained less explored. Here we uncovered the contributions of CFs to gene regulation in the Caenorhabditis elegans intestine. We first annotated 366 CFs encoded by the C. elegans genome and assembled a library of 335 RNAi clones. Using this library, we analyzed the effects of individually depleting these CFs on the expression of 19 fluorescent transcriptional reporters in the intestine and identified 216 regulatory interactions. We found that different CFs interact specifically with different promoters, and that both essential and intestinally expressed CFs exhibit the highest proportion of interactions. We did not find all members of CF complexes acting on the same set of reporters but instead found diversity in the promoter targets of each complex component. Finally, we found that previously identified activation mechanisms for the acdh-1 promoter use different CFs and TFs. Overall, we demonstrate that CFs function specifically rather than ubiquitously at intestinal promoters and provide an RNAi resource for reverse genetic screens.
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8
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Soukup EM, Bettinger JC, Mathies LD. Transcription factors regulating the fate and developmental potential of a multipotent progenitor in Caenorhabditis elegans. G3 (BETHESDA, MD.) 2022; 12:jkac232. [PMID: 36063055 PMCID: PMC9635636 DOI: 10.1093/g3journal/jkac232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 08/30/2022] [Indexed: 06/15/2023]
Abstract
Multipotent stem and progenitor cells have the capacity to generate a limited array of related cell types. The Caenorhabditis elegans somatic gonadal precursors are multipotent progenitors that generate all 143 cells of the somatic gonad, including complex tissues and specialized signaling cells. To screen for candidate regulators of cell fate and multipotency, we identified transcription factor genes with higher expression in somatic gonadal precursors than in their differentiated sister, the head mesodermal cell. We used RNA interference or genetic mutants to reduce the function of 183 of these genes and examined the worms for defects in the somatic gonadal precursor cell fate or the ability to generate gonadal tissue types. We identify 8 genes that regulate somatic gonadal precursor fate, including the SWI/SNF chromatin remodeling complex gene swsn-3 and the Ci/GLI homolog tra-1, which is the terminal regulator of sex determination. Four genes are necessary for somatic gonadal precursors to generate the correct number and type of descendant cells. We show that the E2F homolog, efl-3, regulates the cell fate decision between distal tip cells and the sheath/spermathecal precursor. We find that the FACT complex gene hmg-4 is required for the generation of the correct number of somatic gonadal precursor descendants, and we define an earlier role for the nhr-25 nuclear hormone receptor-encoding gene, in addition to its previously described role in regulating the asymmetric division of somatic gonadal precursors. Overall, our data show that genes regulating cell fate are largely different from genes regulating developmental potential, demonstrating that these processes are genetically separable.
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Affiliation(s)
- Evan M Soukup
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA 23298-0613, USA
| | - Jill C Bettinger
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA 23298-0613, USA
| | - Laura D Mathies
- Corresponding author: Department of Pharmacology and Toxicology, Virginia Commonwealth University, Box 980613, Richmond, VA 23298-0613, USA.
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9
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Gang SS, Grover M, Reddy KC, Raman D, Chang YT, Ekiert DC, Barkoulas M, Troemel ER. A pals-25 gain-of-function allele triggers systemic resistance against natural pathogens of C. elegans. PLoS Genet 2022; 18:e1010314. [PMID: 36191002 PMCID: PMC9560605 DOI: 10.1371/journal.pgen.1010314] [Citation(s) in RCA: 9] [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: 06/27/2022] [Revised: 10/13/2022] [Accepted: 09/15/2022] [Indexed: 11/15/2022] Open
Abstract
Regulation of immunity throughout an organism is critical for host defense. Previous studies in the nematode Caenorhabditis elegans have described an "ON/OFF" immune switch comprised of the antagonistic paralogs PALS-25 and PALS-22, which regulate resistance against intestinal and epidermal pathogens. Here, we identify and characterize a PALS-25 gain-of-function mutant protein with a premature stop (Q293*), which we find is freed from physical repression by its negative regulator, the PALS-22 protein. PALS-25(Q293*) activates two related gene expression programs, the Oomycete Recognition Response (ORR) against natural pathogens of the epidermis, and the Intracellular Pathogen Response (IPR) against natural intracellular pathogens of the intestine. A subset of ORR/IPR genes is upregulated in pals-25(Q293*) mutants, and they are resistant to oomycete infection in the epidermis, and microsporidia and virus infection in the intestine, but without compromising growth. Surprisingly, we find that activation of PALS-25 seems to primarily stimulate the downstream bZIP transcription factor ZIP-1 in the epidermis, with upregulation of gene expression in both the epidermis and in the intestine. Interestingly, we find that PALS-22/25-regulated epidermal-to-intestinal signaling promotes resistance to the N. parisii intestinal pathogen, demonstrating cross-tissue protective immune induction from one epithelial tissue to another in C. elegans.
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Affiliation(s)
- Spencer S. Gang
- School of Biological Sciences, University of California, San Diego, La Jolla, California, United States of America
| | - Manish Grover
- Department of Life Sciences, Imperial College, London, United Kingdom
| | - Kirthi C. Reddy
- School of Biological Sciences, University of California, San Diego, La Jolla, California, United States of America
| | - Deevya Raman
- School of Biological Sciences, University of California, San Diego, La Jolla, California, United States of America
| | - Ya-Ting Chang
- Departments of Cell Biology and Microbiology, New York University School of Medicine, New York, New York, United States of America
| | - Damian C. Ekiert
- Departments of Cell Biology and Microbiology, New York University School of Medicine, New York, New York, United States of America
| | | | - Emily R. Troemel
- School of Biological Sciences, University of California, San Diego, La Jolla, California, United States of America
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10
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Bhattacharya S, Horowitz BB, Zhang J, Li X, Zhang H, Giese GE, Holdorf AD, Walhout AJ. A metabolic regulatory network for the Caenorhabditis elegans intestine. iScience 2022; 25:104688. [PMID: 35847555 PMCID: PMC9283940 DOI: 10.1016/j.isci.2022.104688] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 06/12/2022] [Accepted: 06/24/2022] [Indexed: 11/12/2022] Open
Abstract
Metabolic perturbations can affect gene expression, for instance to rewire metabolism. While numerous efforts have measured gene expression in response to individual metabolic perturbations, methods that determine all metabolic perturbations that affect the expression for a given gene or set of genes have not been available. Here, we use a gene-centered approach to derive a first-pass metabolic regulatory network for Caenorhabditis elegans by performing RNAi of more than 1,400 metabolic genes with a set of 19 promoter reporter strains that express a fluorescent protein in the animal's intestine. We find that metabolic perturbations generally increase promoter activity, which contrasts with transcription factor (TF) RNAi, which tends to repress promoter activity. We identify several TFs that modulate promoter activity in response to perturbations of the electron transport chain and explore complex genetic interactions among metabolic pathways. This work provides a blueprint for a systems-level understanding of how metabolism affects gene expression.
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Affiliation(s)
- Sushila Bhattacharya
- Department of Systems Biology, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA
| | - Brent B. Horowitz
- Department of Systems Biology, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA
| | - Jingyan Zhang
- Department of Systems Biology, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA
| | - Xuhang Li
- Department of Systems Biology, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA
| | - Hefei Zhang
- Department of Systems Biology, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA
| | - Gabrielle E. Giese
- Department of Systems Biology, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA
| | - Amy D. Holdorf
- Department of Systems Biology, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA
| | - Albertha J.M. Walhout
- Department of Systems Biology, University of Massachusetts Chan Medical School, Worcester, MA 01605, USA
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11
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Li J, Sun C, Zheng J, Li J, Yi G, Yang N. Time-Course Transcriptional and Chromatin Accessibility Profiling Reveals Genes Associated With Asymmetrical Gonadal Development in Chicken Embryos. Front Cell Dev Biol 2022; 10:832132. [PMID: 35345851 PMCID: PMC8957256 DOI: 10.3389/fcell.2022.832132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Accepted: 02/09/2022] [Indexed: 12/02/2022] Open
Abstract
In birds, male gonads form on both sides whereas most females develop asymmetric gonads. Multiple early lines of evidence suggested that the right gonad fails to develop into a functional ovary, mainly due to differential expression of PITX2 in the gonadal epithelium. Despite some advances in recent years, the molecular mechanisms underlying asymmetric gonadal development remain unclear. Here, using bulk analysis of whole gonads, we established a relatively detailed profile of four representative stages of chicken gonadal development at the transcriptional and chromatin levels. We revealed that many candidate genes were significantly enriched in morphogenesis, meiosis and subcellular structure formation, which may be responsible for asymmetric gonadal development. Further chromatin accessibility analysis suggested that the transcriptional activities of the candidate genes might be regulated by nearby open chromatin regions, which may act as transcription factor (TF) binding sites and potential cis-regulatory elements. We found that LHX9 was a promising TF that bound to the left-biased peaks of many cell cycle-related genes. In summary, this study provides distinctive insights into the potential molecular basis underlying the asymmetric development of chicken gonads.
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Affiliation(s)
- Jianbo Li
- National Engineering Laboratory for Animal Breeding and Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Congjiao Sun
- National Engineering Laboratory for Animal Breeding and Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Jiangxia Zheng
- National Engineering Laboratory for Animal Breeding and Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Junying Li
- National Engineering Laboratory for Animal Breeding and Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Guoqiang Yi
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
| | - Ning Yang
- National Engineering Laboratory for Animal Breeding and Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, College of Animal Science and Technology, China Agricultural University, Beijing, China
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12
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Cuperus JT. Single-cell genomics in plants: current state, future directions, and hurdles to overcome. PLANT PHYSIOLOGY 2022; 188:749-755. [PMID: 34662424 PMCID: PMC8825463 DOI: 10.1093/plphys/kiab478] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 09/21/2021] [Indexed: 05/26/2023]
Abstract
Single-cell genomics has the potential to revolutionize the study of plant development and tissue-specific responses to environmental stimuli by revealing heretofore unknown players and gene regulatory processes. Here, I focus on the current state of single-cell genomics in plants, emerging technologies and applications, in addition to outlining possible future directions for experiments. I describe approaches to enable cheaper and larger experiments and technologies to measure multiple types of molecules to better model and understand cell types and their different states and trajectories throughout development. Lastly, I discuss the inherent limitations of single-cell studies and the technological hurdles that need to be overcome to widely apply single-cell genomics in crops to generate the greatest possible knowledge gain.
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Affiliation(s)
- Josh T Cuperus
- Department of Genome Sciences, University of Washington, Seattle, Washington, USA
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13
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Zhang Y, Zhu L, Wang X. NEM-Tar: A Probabilistic Graphical Model for Cancer Regulatory Network Inference and Prioritization of Potential Therapeutic Targets From Multi-Omics Data. Front Genet 2021; 12:608042. [PMID: 33968127 PMCID: PMC8100334 DOI: 10.3389/fgene.2021.608042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Accepted: 03/22/2021] [Indexed: 11/13/2022] Open
Abstract
Targeted therapy has been widely adopted as an effective treatment strategy to battle against cancer. However, cancers are not single disease entities, but comprising multiple molecularly distinct subtypes, and the heterogeneity nature prevents precise selection of patients for optimized therapy. Dissecting cancer subtype-specific signaling pathways is crucial to pinpointing dysregulated genes for the prioritization of novel therapeutic targets. Nested effects models (NEMs) are a group of graphical models that encode subset relations between observed downstream effects under perturbations to upstream signaling genes, providing a prototype for mapping the inner workings of the cell. In this study, we developed NEM-Tar, which extends the original NEMs to predict drug targets by incorporating causal information of (epi)genetic aberrations for signaling pathway inference. An information theory-based score, weighted information gain (WIG), was proposed to assess the impact of signaling genes on a specific downstream biological process of interest. Subsequently, we conducted simulation studies to compare three inference methods and found that the greedy hill-climbing algorithm demonstrated the highest accuracy and robustness to noise. Furthermore, two case studies were conducted using multi-omics data for colorectal cancer (CRC) and gastric cancer (GC) in the TCGA database. Using NEM-Tar, we inferred signaling networks driving the poor-prognosis subtypes of CRC and GC, respectively. Our model prioritized not only potential individual drug targets such as HER2, for which FDA-approved inhibitors are available but also the combinations of multiple targets potentially useful for the design of combination therapies.
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Affiliation(s)
- Yuchen Zhang
- Department of Biomedical Sciences, City University of Hong Kong, Hong Kong, China
| | - Lina Zhu
- Department of Biomedical Sciences, City University of Hong Kong, Hong Kong, China
| | - Xin Wang
- Department of Biomedical Sciences, City University of Hong Kong, Hong Kong, China.,Key Laboratory of Biochip Technology, Biotech and Health Centre, Shenzhen Research Institute, City University of Hong Kong, Shenzhen, China
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14
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Bhatia S, Kumar H, Mahajan M, Yadav S, Saini P, Yadav S, Sahu SK, Sundaram JK, Yadav RK. A cellular expression map of epidermal and subepidermal cell layer-enriched transcription factor genes integrated with the regulatory network in Arabidopsis shoot apical meristem. PLANT DIRECT 2021; 5:e00306. [PMID: 33748654 PMCID: PMC7970154 DOI: 10.1002/pld3.306] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 11/22/2020] [Accepted: 01/03/2021] [Indexed: 06/12/2023]
Abstract
Transcriptional control of gene expression is an exquisitely regulated process in both animals and plants. Transcription factors (TFs) and the regulatory networks that drive the expression of TF genes in epidermal and subepidermal cell layers in Arabidopsis are unexplored. Here, we identified 65 TF genes enriched in the epidermal and subepidermal cell layers of the shoot apical meristem (SAM). To determine the cell type specificity in different stages of Arabidopsis development, we made YFP based transcriptional fusion constructs by taking a 3-kb upstream noncoding region above the translation start site. Here, we report that for ~52% (22/42) TF genes, we detected transcription activity. TF genes derived from epidermis show uniform expression in early embryo development; however, in the late globular stage, their transcription activity is suppressed in the inner cell layers. Expression patterns linked to subepidermal cell layer identity were apparent in the postembryonic development. Potential upstream regulators that could modulate the activity of epidermal and subepidermal cell layer-enriched TF genes were identified using enhanced yeast-one-hybrid (eY1H) assay and validated. This study describes the activation of TF genes in epidermal and subepidermal cell layers in embryonic and postembryonic development of Arabidopsis shoot apex.
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Affiliation(s)
- Shivani Bhatia
- Department of Biological SciencesIndian Institute of Science Education and Research MohaliPunjabIndia
| | - Harish Kumar
- Department of Biological SciencesIndian Institute of Science Education and Research MohaliPunjabIndia
| | - Monika Mahajan
- Department of Biological SciencesIndian Institute of Science Education and Research MohaliPunjabIndia
| | - Sonal Yadav
- Department of Biological SciencesIndian Institute of Science Education and Research MohaliPunjabIndia
| | - Prince Saini
- Department of Biological SciencesIndian Institute of Science Education and Research MohaliPunjabIndia
| | - Shalini Yadav
- Department of Biological SciencesIndian Institute of Science Education and Research MohaliPunjabIndia
| | - Sangram Keshari Sahu
- Department of Biological SciencesIndian Institute of Science Education and Research MohaliPunjabIndia
| | - Jayesh Kumar Sundaram
- Department of Biological SciencesIndian Institute of Science Education and Research MohaliPunjabIndia
- Present address:
Department of Biological SciencesUniversity of PittsburghPittsburghPAUSA
| | - Ram Kishor Yadav
- Department of Biological SciencesIndian Institute of Science Education and Research MohaliPunjabIndia
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15
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Waylen LN, Nim HT, Martelotto LG, Ramialison M. From whole-mount to single-cell spatial assessment of gene expression in 3D. Commun Biol 2020; 3:602. [PMID: 33097816 PMCID: PMC7584572 DOI: 10.1038/s42003-020-01341-1] [Citation(s) in RCA: 67] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Accepted: 09/10/2020] [Indexed: 12/31/2022] Open
Abstract
Unravelling spatio-temporal patterns of gene expression is crucial to understanding core biological principles from embryogenesis to disease. Here we review emerging technologies, providing automated, high-throughput, spatially resolved quantitative gene expression data. Novel techniques expand on current benchmark protocols, expediting their incorporation into ongoing research. These approaches digitally reconstruct patterns of embryonic expression in three dimensions, and have successfully identified novel domains of expression, cell types, and tissue features. Such technologies pave the way for unbiased and exhaustive recapitulation of gene expression levels in spatial and quantitative terms, promoting understanding of the molecular origin of developmental defects, and improving medical diagnostics.
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Affiliation(s)
- Lisa N Waylen
- Australian Regenerative Medicine Institute and Systems Biology Institute, Monash University, Clayton, VIC, Australia
| | - Hieu T Nim
- Australian Regenerative Medicine Institute and Systems Biology Institute, Monash University, Clayton, VIC, Australia
- Transcriptomics and Bioinformatics Group, Murdoch Children's Research Institute, Parkville, VIC, Australia
| | - Luciano G Martelotto
- Single Cell Core Laboratory, Harvard Medical School, Department of System Biology, Boston, MA, USA
| | - Mirana Ramialison
- Australian Regenerative Medicine Institute and Systems Biology Institute, Monash University, Clayton, VIC, Australia.
- Transcriptomics and Bioinformatics Group, Murdoch Children's Research Institute, Parkville, VIC, Australia.
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16
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Littlejohn NK, Seban N, Liu CC, Srinivasan S. A feedback loop governs the relationship between lipid metabolism and longevity. eLife 2020; 9:58815. [PMID: 33078707 PMCID: PMC7575325 DOI: 10.7554/elife.58815] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Accepted: 09/25/2020] [Indexed: 12/16/2022] Open
Abstract
The relationship between lipid metabolism and longevity remains unclear. Although fat oxidation is essential for weight loss, whether it remains beneficial when sustained for long periods, and the extent to which it may attenuate or augment lifespan remain important unanswered questions. Here, we develop an experimental handle in the Caenorhabditis elegans model system, in which we uncover the mechanisms that connect long-term fat oxidation with longevity. We find that sustained β-oxidation via activation of the conserved triglyceride lipase ATGL-1, triggers a feedback transcriptional loop that involves the mito-nuclear transcription factor ATFS-1, and a previously unknown and highly conserved repressor of ATGL-1 called HLH-11/AP4. This feedback loop orchestrates the dual control of fat oxidation and lifespan, and shields the organism from life-shortening mitochondrial stress in the face of continuous fat oxidation. Thus, we uncover one mechanism by which fat oxidation can be sustained for long periods without deleterious effects on longevity.
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Affiliation(s)
- Nicole K Littlejohn
- Department of Neuroscience and The Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, United States
| | - Nicolas Seban
- Department of Neuroscience and The Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, United States
| | - Chung-Chih Liu
- Skaggs Graduate School of Chemical and Biological Sciences, The Scripps Research Institute, La Jolla, United States
| | - Supriya Srinivasan
- Department of Neuroscience and The Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, United States
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17
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Giese GE, Walker MD, Ponomarova O, Zhang H, Li X, Minevich G, Walhout AJ. Caenorhabditis elegans methionine/S-adenosylmethionine cycle activity is sensed and adjusted by a nuclear hormone receptor. eLife 2020; 9:60259. [PMID: 33016879 PMCID: PMC7561351 DOI: 10.7554/elife.60259] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 10/02/2020] [Indexed: 01/17/2023] Open
Abstract
Vitamin B12 is an essential micronutrient that functions in two metabolic pathways: the canonical propionate breakdown pathway and the methionine/S-adenosylmethionine (Met/SAM) cycle. In Caenorhabditis elegans, low vitamin B12, or genetic perturbation of the canonical propionate breakdown pathway results in propionate accumulation and the transcriptional activation of a propionate shunt pathway. This propionate-dependent mechanism requires nhr-10 and is referred to as ‘B12-mechanism-I’. Here, we report that vitamin B12 represses the expression of Met/SAM cycle genes by a propionate-independent mechanism we refer to as ‘B12-mechanism-II’. This mechanism is activated by perturbations in the Met/SAM cycle, genetically or due to low dietary vitamin B12. B12-mechanism-II requires nhr-114 to activate Met/SAM cycle gene expression, the vitamin B12 transporter, pmp-5, and adjust influx and efflux of the cycle by activating msra-1 and repressing cbs-1, respectively. Taken together, Met/SAM cycle activity is sensed and transcriptionally adjusted to be in a tight metabolic regime.
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Affiliation(s)
- Gabrielle E Giese
- Program in Systems Biology and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, United States
| | - Melissa D Walker
- Program in Systems Biology and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, United States
| | - Olga Ponomarova
- Program in Systems Biology and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, United States
| | - Hefei Zhang
- Program in Systems Biology and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, United States
| | - Xuhang Li
- Program in Systems Biology and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, United States
| | - Gregory Minevich
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, United States
| | - Albertha Jm Walhout
- Program in Systems Biology and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, United States
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18
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Yilmaz LS, Li X, Nanda S, Fox B, Schroeder F, Walhout AJ. Modeling tissue-relevant Caenorhabditis elegans metabolism at network, pathway, reaction, and metabolite levels. Mol Syst Biol 2020; 16:e9649. [PMID: 33022146 PMCID: PMC7537831 DOI: 10.15252/msb.20209649] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 09/10/2020] [Accepted: 09/11/2020] [Indexed: 01/04/2023] Open
Abstract
Metabolism is a highly compartmentalized process that provides building blocks for biomass generation during development, homeostasis, and wound healing, and energy to support cellular and organismal processes. In metazoans, different cells and tissues specialize in different aspects of metabolism. However, studying the compartmentalization of metabolism in different cell types in a whole animal and for a particular stage of life is difficult. Here, we present MEtabolic models Reconciled with Gene Expression (MERGE), a computational pipeline that we used to predict tissue-relevant metabolic function at the network, pathway, reaction, and metabolite levels based on single-cell RNA-sequencing (scRNA-seq) data from the nematode Caenorhabditis elegans. Our analysis recapitulated known tissue functions in C. elegans, captured metabolic properties that are shared with similar tissues in human, and provided predictions for novel metabolic functions. MERGE is versatile and applicable to other systems. We envision this work as a starting point for the development of metabolic network models for individual cells as scRNA-seq continues to provide higher-resolution gene expression data.
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Affiliation(s)
- Lutfu Safak Yilmaz
- Program in Systems Biology, Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Xuhang Li
- Program in Systems Biology, Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Shivani Nanda
- Program in Systems Biology, Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Bennett Fox
- Boyce Thompson Institute, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, USA
| | - Frank Schroeder
- Boyce Thompson Institute, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, USA
| | - Albertha Jm Walhout
- Program in Systems Biology, Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA
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19
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Abete-Luzi P, Fukushige T, Yun S, Krause MW, Eisenmann DM. New Roles for the Heterochronic Transcription Factor LIN-29 in Cuticle Maintenance and Lipid Metabolism at the Larval-to-Adult Transition in Caenorhabditis elegans. Genetics 2020; 214:669-690. [PMID: 31974205 PMCID: PMC7054012 DOI: 10.1534/genetics.119.302860] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Accepted: 01/21/2020] [Indexed: 11/18/2022] Open
Abstract
Temporal regulation of gene expression is a crucial aspect of metazoan development. In the roundworm Caenorhabditis elegans, the heterochronic pathway controls multiple developmental events in a time-specific manner. The most downstream effector of this pathway, the zinc-finger transcription factor LIN-29, acts in the last larval stage (L4) to regulate elements of the larval-to-adult switch. Here, we explore new LIN-29 targets and their implications for this developmental transition. We used RNA-sequencing to identify genes differentially expressed between animals misexpressing LIN-29 at an early time point and control animals. Among 230 LIN-29-activated genes, we found that genes encoding cuticle collagens were overrepresented. Interestingly, expression of lin-29 and some of these collagens was increased in adults with cuticle damage, suggesting a previously unknown function for LIN-29 in adult cuticle maintenance. On the other hand, genes involved in fat metabolism were enriched among 350 LIN-29-downregulated targets. We used mass spectrometry to assay lipid content in animals overexpressing LIN-29 and observed reduced fatty acid levels. Many LIN-29-repressed genes are normally expressed in the intestine, suggesting cell-nonautonomous regulation. We identified several LIN-29 upregulated genes encoding signaling molecules that may act as mediators in the regulation of intestinally expressed genes encoding fat metabolic enzymes and vitellogenins. Overall, our results support the model of LIN-29 as a major regulator of adult cuticle synthesis and integrity, and as the trigger for metabolic changes that take place at the important transition from rapid growth during larval life to slower growth and offspring production during adulthood.
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Affiliation(s)
- Patricia Abete-Luzi
- Department of Biological Sciences, University of Maryland Baltimore County, Baltimore, Maryland 21250
| | - Tetsunari Fukushige
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892
| | - Sijung Yun
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892
| | - Michael W Krause
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892
| | - David M Eisenmann
- Department of Biological Sciences, University of Maryland Baltimore County, Baltimore, Maryland 21250
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20
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Shao H, Wang D. Long-term and low-dose exposure to nanopolystyrene induces a protective strategy to maintain functional state of intestine barrier in nematode Caenorhabditis elegans. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 258:113649. [PMID: 31767235 DOI: 10.1016/j.envpol.2019.113649] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2019] [Revised: 11/01/2019] [Accepted: 11/18/2019] [Indexed: 06/10/2023]
Abstract
Functional state of intestinal barrier plays an important role for environmental animals in being against various toxicants. We investigated GATA transcriptional factor ELT-2-mediated intestinal response to nanopolystyrere in Caenorhabditis elegans. Prolonged exposure to nanopolystyrene (≥1 μg/L) induced an increase in expression of ELT-2, and intestinal RNA interference (RNAi) knockdown of elt-2 caused enhancement in intestinal permeability. Meanwhile, mutation of elt-2 resulted in susceptibility to nanopolystyrene toxicity, and ELT-2 functioned in intestine to regulate the nanopolystyrene toxicity. ERM-1, CLEC-63, and CLEC-85 were identified as targets of ELT-2 in regulating the nanopolystyrene toxicity. ERM-1 was required for maintaining functional state in intestinal barrier, and functioned synergistically with CLEC-63 or CLEC-85 to regulate nanopolystyrene toxicity. Therefore, activation of intestinal ELT-2 by nanopolystyrere could mediate a protective strategy to maintain the functional state of intestinal barrier. During this process, intestinal ELT-2 activated two different molecular signals (ERM-1 signal and CLEC-63/85 signal) for nematodes against the nanopolystyrene toxicity.
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Affiliation(s)
- Huimin Shao
- Medical School, Southeast University, Nanjing, 210009, China
| | - Dayong Wang
- Medical School, Southeast University, Nanjing, 210009, China.
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21
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Bulcha JT, Giese GE, Ali MZ, Lee YU, Walker MD, Holdorf AD, Yilmaz LS, Brewster RC, Walhout AJM. A Persistence Detector for Metabolic Network Rewiring in an Animal. Cell Rep 2020; 26:460-468.e4. [PMID: 30625328 PMCID: PMC6368391 DOI: 10.1016/j.celrep.2018.12.064] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 11/06/2018] [Accepted: 12/14/2018] [Indexed: 11/25/2022] Open
Abstract
Biological systems must possess mechanisms that prevent inappropriate responses to spurious environmental inputs. Caenorhabditis elegans has two breakdown pathways for the short-chain fatty acid propionate: a canonical, vitamin B12-dependent pathway and a propionate shunt that is used when vitamin B12 levels are low. The shunt pathway is kept off when there is sufficient flux through the canonical pathway, likely to avoid generating shunt-specific toxic intermediates. Here, we discovered a transcriptional regulatory circuit that activates shunt gene expression upon propionate buildup. Nuclear hormone receptor 10 (NHR-10) and NHR-68 function together as a "persistence detector" in a type 1, coherent feed-forward loop with an AND-logic gate to delay shunt activation upon propionate accumulation and to avoid spurious shunt activation in response to a non-sustained pulse of propionate. Together, our findings identify a persistence detector in an animal, which transcriptionally rewires propionate metabolism to maintain homeostasis.
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Affiliation(s)
- Jote T Bulcha
- Program in Systems Biology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Gabrielle E Giese
- Program in Systems Biology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Md Zulfikar Ali
- Program in Systems Biology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Yong-Uk Lee
- Program in Systems Biology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Melissa D Walker
- Program in Systems Biology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Amy D Holdorf
- Program in Systems Biology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - L Safak Yilmaz
- Program in Systems Biology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Robert C Brewster
- Program in Systems Biology, University of Massachusetts Medical School, Worcester, MA 01605, USA; Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Albertha J M Walhout
- Program in Systems Biology, University of Massachusetts Medical School, Worcester, MA 01605, USA; Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA.
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22
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Yang Y, Shao H, Wu Q, Wang D. Lipid metabolic response to polystyrene particles in nematode Caenorhabditis elegans. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 256:113439. [PMID: 31672355 DOI: 10.1016/j.envpol.2019.113439] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Revised: 10/05/2019] [Accepted: 10/18/2019] [Indexed: 06/10/2023]
Abstract
Nanoplastics can be used in various fields, such as personal care products. Nevertheless, the effect of nanoplastic exposure on metabolism and its association with stress response remain largely unclear. Using Caenorhabditis elegans as an animal model, we determined the effect of nanopolystyrene exposure on lipid metabolism and its association with the response to nanopolystyrene. Exposure (from L1-larave to adult day-3) to 100 nm nanopolystyrene (≥1 μg/L) induced severe lipid accumulation and increase in expressions of mdt-15 and sbp-1 encoding two lipid metabolic sensors. Meanwhile, we found that SBP-1 acted downstream of intestinal MDT-15 during the control of response to nanopolystyrene. Intestinal transcriptional factor SBP-1 activated two downstream targets, fatty acyl CoA desaturase FAT-6 and heat-shock protein HSP-4 (a marker of endoplasmic reticulum unfolded protein response (ER UPR)) to regulate nanopolystyrene toxicity. Both MDT-15 and SBP-1 were involved in the activation of ER-UPR in nanopolystyrene exposed nematodes. Moreover, SBP-1 regulated the innate immune response by activating FAT-6 in nanopolystyrene exposed nematodes. In the intestine, function of MDT-15 and SBP-1 in regulating nanopolystyrene toxicity was under the control of upstream signaling cascade (PMK-1-SKN-1) in p38 MAPK signaling pathway. Therefore, our data raised an important molecular basis for potential protective function of lipid metabolic response in nanopolystyrene exposed nematodes.
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Affiliation(s)
- Yunhan Yang
- Key Laboratory of Environmental Medicine Engineering in Ministry of Education, Medical School, Southeast University, Nanjing 210009, China
| | - Huimin Shao
- Key Laboratory of Environmental Medicine Engineering in Ministry of Education, Medical School, Southeast University, Nanjing 210009, China
| | - Qiuli Wu
- Key Laboratory of Environmental Medicine Engineering in Ministry of Education, Medical School, Southeast University, Nanjing 210009, China
| | - Dayong Wang
- Key Laboratory of Environmental Medicine Engineering in Ministry of Education, Medical School, Southeast University, Nanjing 210009, China.
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23
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Bui LT, Ragsdale EJ. Multiple plasticity regulators reveal targets specifying an induced predatory form in nematodes. Mol Biol Evol 2019; 36:2387-2399. [PMID: 31364718 DOI: 10.1093/molbev/msz171] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 06/19/2019] [Accepted: 07/17/2019] [Indexed: 12/19/2022] Open
Abstract
The ability to translate a single genome into multiple phenotypes, or developmental plasticity, defines how phenotype derives from more than just genes. However, to study the evolutionary targets of plasticity and their evolutionary fates, we need to understand how genetic regulators of plasticity control downstream gene expression. Here, we have identified a transcriptional response specific to polyphenism (i.e., discrete plasticity) in the nematode Pristionchus pacificus. This species produces alternative resource-use morphs - microbivorous and predatory forms, differing in the form of their teeth, a morphological novelty - as influenced by resource availability. Transcriptional profiles common to multiple polyphenism-controlling genes in P. pacificus reveal a suite of environmentally sensitive loci, or ultimate target genes, that make up an induced developmental response. Additionally, in vitro assays show that one polyphenism regulator, the nuclear receptor (NR) NHR-40, physically binds to promoters with putative HNF4⍺ (the NR class including NHR-40) binding sites, suggesting this receptor may directly regulate genes that describe alternative morphs. Among differentially expressed genes were morph-limited genes, highlighting factors with putative "on-off" function in plasticity regulation. Further, predatory morph-biased genes included candidates - namely, all four P. pacificus homologs of Hsp70, which have HNF4⍺ motifs - whose natural variation in expression matches phenotypic differences among P. pacificus wild isolates. In summary, our study links polyphenism regulatory loci to the transcription producing alternative forms of a morphological novelty. Consequently, our findings establish a platform for determining how specific regulators of morph-biased genes may influence selection on plastic phenotypes.
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Affiliation(s)
- Linh T Bui
- Department of Biology, Indiana University, Bloomington, IN
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24
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Bysani M, Agren R, Davegårdh C, Volkov P, Rönn T, Unneberg P, Bacos K, Ling C. ATAC-seq reveals alterations in open chromatin in pancreatic islets from subjects with type 2 diabetes. Sci Rep 2019; 9:7785. [PMID: 31123324 PMCID: PMC6533306 DOI: 10.1038/s41598-019-44076-8] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2018] [Accepted: 05/08/2019] [Indexed: 01/08/2023] Open
Abstract
Impaired insulin secretion from pancreatic islets is a hallmark of type 2 diabetes (T2D). Altered chromatin structure may contribute to the disease. We therefore studied the impact of T2D on open chromatin in human pancreatic islets. We used assay for transposase-accessible chromatin using sequencing (ATAC-seq) to profile open chromatin in islets from T2D and non-diabetic donors. We identified 57,105 and 53,284 ATAC-seq peaks representing open chromatin regions in islets of non-diabetic and diabetic donors, respectively. The majority of ATAC-seq peaks mapped near transcription start sites. Additionally, peaks were enriched in enhancer regions and in regions where islet-specific transcription factors (TFs), e.g. FOXA2, MAFB, NKX2.2, NKX6.1 and PDX1, bind. Islet ATAC-seq peaks overlap with 13 SNPs associated with T2D (e.g. rs7903146, rs2237897, rs757209, rs11708067 and rs878521 near TCF7L2, KCNQ1, HNF1B, ADCY5 and GCK, respectively) and with additional 67 SNPs in LD with known T2D SNPs (e.g. SNPs annotated to GIPR, KCNJ11, GLIS3, IGF2BP2, FTO and PPARG). There was enrichment of open chromatin regions near highly expressed genes in human islets. Moreover, 1,078 open chromatin peaks, annotated to 898 genes, differed in prevalence between diabetic and non-diabetic islet donors. Some of these peaks are annotated to candidate genes for T2D and islet dysfunction (e.g. HHEX, HMGA2, GLIS3, MTNR1B and PARK2) and some overlap with SNPs associated with T2D (e.g. rs3821943 near WFS1 and rs508419 near ANK1). Enhancer regions and motifs specific to key TFs including BACH2, FOXO1, FOXA2, NEUROD1, MAFA and PDX1 were enriched in differential islet ATAC-seq peaks of T2D versus non-diabetic donors. Our study provides new understanding into how T2D alters the chromatin landscape, and thereby accessibility for TFs and gene expression, in human pancreatic islets.
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Affiliation(s)
- Madhusudhan Bysani
- Epigenetics and Diabetes Unit, Department of Clinical Sciences, Lund University Diabetes Centre, Lund University, Scania University Hospital, Malmö, Sweden
| | - Rasmus Agren
- Department of Biology and Biological Engineering, National Bioinformatics Infrastructure Sweden, Science for Life Laboratory, Chalmers University of Technology, Göteborg, Sweden
| | - Cajsa Davegårdh
- Epigenetics and Diabetes Unit, Department of Clinical Sciences, Lund University Diabetes Centre, Lund University, Scania University Hospital, Malmö, Sweden
| | - Petr Volkov
- Epigenetics and Diabetes Unit, Department of Clinical Sciences, Lund University Diabetes Centre, Lund University, Scania University Hospital, Malmö, Sweden
| | - Tina Rönn
- Epigenetics and Diabetes Unit, Department of Clinical Sciences, Lund University Diabetes Centre, Lund University, Scania University Hospital, Malmö, Sweden
| | - Per Unneberg
- Department of Cell and Molecular Biology, National Bioinformatics Infrastructure Sweden, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Karl Bacos
- Epigenetics and Diabetes Unit, Department of Clinical Sciences, Lund University Diabetes Centre, Lund University, Scania University Hospital, Malmö, Sweden
| | - Charlotte Ling
- Epigenetics and Diabetes Unit, Department of Clinical Sciences, Lund University Diabetes Centre, Lund University, Scania University Hospital, Malmö, Sweden.
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25
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Steuernagel L, Meckbach C, Heinrich F, Zeidler S, Schmitt AO, Gültas M. Computational identification of tissue-specific transcription factor cooperation in ten cattle tissues. PLoS One 2019; 14:e0216475. [PMID: 31095599 PMCID: PMC6522001 DOI: 10.1371/journal.pone.0216475] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Accepted: 04/22/2019] [Indexed: 01/01/2023] Open
Abstract
Transcription factors (TFs) are a special class of DNA-binding proteins that orchestrate gene transcription by recruiting other TFs, co-activators or co-repressors. Their combinatorial interplay in higher organisms maintains homeostasis and governs cell identity by finely controlling and regulating tissue-specific gene expression. Despite the rich literature on the importance of cooperative TFs for deciphering the mechanisms of individual regulatory programs that control tissue specificity in several organisms such as human, mouse, or Drosophila melanogaster, to date, there is still need for a comprehensive study to detect specific TF cooperations in regulatory processes of cattle tissues. To address the needs of knowledge about specific combinatorial gene regulation in cattle tissues, we made use of three publicly available RNA-seq datasets and obtained tissue-specific gene (TSG) sets for ten tissues (heart, lung, liver, kidney, duodenum, muscle tissue, adipose tissue, colon, spleen and testis). By analyzing these TSG-sets, tissue-specific TF cooperations of each tissue have been identified. The results reveal that similar to the combinatorial regulatory events of model organisms, TFs change their partners depending on their biological functions in different tissues. Particularly with regard to preferential partner choice of the transcription factors STAT3 and NR2C2, this phenomenon has been highlighted with their five different specific cooperation partners in multiple tissues. The information about cooperative TFs could be promising: i) to understand the molecular mechanisms of regulating processes; and ii) to extend the existing knowledge on the importance of single TFs in cattle tissues.
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Affiliation(s)
- Lukas Steuernagel
- Breeding Informatics Group, Department of Animal Sciences, Georg-August University, Margarethe von Wrangell-Weg 7, 37075 Göttingen, Germany
| | - Cornelia Meckbach
- Institute of Medical Bioinformatics, Goldschmidtstraße 1, University Medical Center Göttingen, Georg-August-University, 37077 Göttingen, Germany
| | - Felix Heinrich
- Breeding Informatics Group, Department of Animal Sciences, Georg-August University, Margarethe von Wrangell-Weg 7, 37075 Göttingen, Germany
| | - Sebastian Zeidler
- Breeding Informatics Group, Department of Animal Sciences, Georg-August University, Margarethe von Wrangell-Weg 7, 37075 Göttingen, Germany
| | - Armin O. Schmitt
- Breeding Informatics Group, Department of Animal Sciences, Georg-August University, Margarethe von Wrangell-Weg 7, 37075 Göttingen, Germany
- Center for Integrated Breeding Research (CiBreed), Albrecht-Thaer-Weg 3, Georg-August University, 37075, Göttingen, Germany
| | - Mehmet Gültas
- Breeding Informatics Group, Department of Animal Sciences, Georg-August University, Margarethe von Wrangell-Weg 7, 37075 Göttingen, Germany
- Center for Integrated Breeding Research (CiBreed), Albrecht-Thaer-Weg 3, Georg-August University, 37075, Göttingen, Germany
- * E-mail:
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26
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Alexandre CM, Urton JR, Jean-Baptiste K, Huddleston J, Dorrity MW, Cuperus JT, Sullivan AM, Bemm F, Jolic D, Arsovski AA, Thompson A, Nemhauser JL, Fields S, Weigel D, Bubb KL, Queitsch C. Complex Relationships between Chromatin Accessibility, Sequence Divergence, and Gene Expression in Arabidopsis thaliana. Mol Biol Evol 2019; 35:837-854. [PMID: 29272536 DOI: 10.1093/molbev/msx326] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Variation in regulatory DNA is thought to drive phenotypic variation, evolution, and disease. Prior studies of regulatory DNA and transcription factors across animal species highlighted a fundamental conundrum: Transcription factor binding domains and cognate binding sites are conserved, while regulatory DNA sequences are not. It remains unclear how conserved transcription factors and dynamic regulatory sites produce conserved expression patterns across species. Here, we explore regulatory DNA variation and its functional consequences within Arabidopsis thaliana, using chromatin accessibility to delineate regulatory DNA genome-wide. Unlike in previous cross-species comparisons, the positional homology of regulatory DNA is maintained among A. thaliana ecotypes and less nucleotide divergence has occurred. Of the ∼50,000 regulatory sites in A. thaliana, we found that 15% varied in accessibility among ecotypes. Some of these accessibility differences were associated with extensive, previously unannotated sequence variation, encompassing many deletions and ancient hypervariable alleles. Unexpectedly, for the majority of such regulatory sites, nearby gene expression was unaffected. Nevertheless, regulatory sites with high levels of sequence variation and differential chromatin accessibility were the most likely to be associated with differential gene expression. Finally, and most surprising, we found that the vast majority of differentially accessible sites show no underlying sequence variation. We argue that these surprising results highlight the necessity to consider higher-order regulatory context in evaluating regulatory variation and predicting its phenotypic consequences.
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Affiliation(s)
| | - James R Urton
- Department of Genome Sciences, University of Washington, Seattle, WA
| | - Ken Jean-Baptiste
- Department of Genome Sciences, University of Washington, Seattle, WA
| | - John Huddleston
- Department of Genome Sciences, University of Washington, Seattle, WA.,Molecular and Cellular Biology Graduate Program, University of Washington, Seattle, WA
| | - Michael W Dorrity
- Department of Genome Sciences, University of Washington, Seattle, WA
| | - Josh T Cuperus
- Department of Genome Sciences, University of Washington, Seattle, WA
| | | | - Felix Bemm
- Department of Molecular Biology, Max Planck Institute for Developmental Biology, Tübingen, Germany
| | - Dino Jolic
- Department of Molecular Biology, Max Planck Institute for Developmental Biology, Tübingen, Germany
| | | | | | | | - Stan Fields
- Department of Genome Sciences, University of Washington, Seattle, WA.,Howard Hughes Medical Institute, University of Washington, Seattle, WA
| | - Detlef Weigel
- Department of Molecular Biology, Max Planck Institute for Developmental Biology, Tübingen, Germany
| | - Kerry L Bubb
- Department of Genome Sciences, University of Washington, Seattle, WA
| | - Christin Queitsch
- Department of Genome Sciences, University of Washington, Seattle, WA
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27
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Peterson ND, Cheesman HK, Liu P, Anderson SM, Foster KJ, Chhaya R, Perrat P, Thekkiniath J, Yang Q, Haynes CM, Pukkila-Worley R. The nuclear hormone receptor NHR-86 controls anti-pathogen responses in C. elegans. PLoS Genet 2019; 15:e1007935. [PMID: 30668573 PMCID: PMC6358101 DOI: 10.1371/journal.pgen.1007935] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 02/01/2019] [Accepted: 01/04/2019] [Indexed: 12/16/2022] Open
Abstract
Nuclear hormone receptors (NHRs) are ligand-gated transcription factors that control adaptive host responses following recognition of specific endogenous or exogenous ligands. Although NHRs have expanded dramatically in C. elegans compared to other metazoans, the biological function of only a few of these genes has been characterized in detail. Here, we demonstrate that an NHR can activate an anti-pathogen transcriptional program. Using genetic epistasis experiments, transcriptome profiling analyses and chromatin immunoprecipitation-sequencing, we show that, in the presence of an immunostimulatory small molecule, NHR-86 binds to the promoters of immune effectors to activate their transcription. NHR-86 is not required for resistance to the bacterial pathogen Pseudomonas aeruginosa at baseline, but activation of NHR-86 by this compound drives a transcriptional program that provides protection against this pathogen. Interestingly, NHR-86 targets immune effectors whose basal regulation requires the canonical p38 MAPK PMK-1 immune pathway. However, NHR-86 functions independently of PMK-1 and modulates the transcription of these infection response genes directly. These findings characterize a new transcriptional regulator in C. elegans that can induce a protective host response towards a bacterial pathogen.
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Affiliation(s)
- Nicholas D. Peterson
- Program in Innate Immunity, Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, MA, United States of America
| | - Hilary K. Cheesman
- Program in Innate Immunity, Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, MA, United States of America
| | - Pengpeng Liu
- Department of Molecular, Cell and Cancer Biology, University of Massachusetts Medical School, Worcester, MA, United States of America
| | - Sarah M. Anderson
- Program in Innate Immunity, Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, MA, United States of America
| | - Kyle J. Foster
- Program in Innate Immunity, Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, MA, United States of America
| | - Richa Chhaya
- Program in Innate Immunity, Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, MA, United States of America
| | - Paola Perrat
- Department of Neurobiology, University of Massachusetts Medical School, Worcester, MA, United States of America
| | - Jose Thekkiniath
- Program in Innate Immunity, Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, MA, United States of America
| | - Qiyuan Yang
- Department of Molecular, Cell and Cancer Biology, University of Massachusetts Medical School, Worcester, MA, United States of America
| | - Cole M. Haynes
- Department of Molecular, Cell and Cancer Biology, University of Massachusetts Medical School, Worcester, MA, United States of America
| | - Read Pukkila-Worley
- Program in Innate Immunity, Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, MA, United States of America
- * E-mail:
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28
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The Caenorhabditis elegans Oxidative Stress Response Requires the NHR-49 Transcription Factor. G3-GENES GENOMES GENETICS 2018; 8:3857-3863. [PMID: 30297383 PMCID: PMC6288832 DOI: 10.1534/g3.118.200727] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The overproduction of reactive oxygen species (ROS) in cells can lead to the development of diseases associated with aging. We have previously shown that C. elegansBRAP-2 (Brca1 associated binding protein 2) regulates phase II detoxification genes such as gst-4, by increasing SKN-1 activity. Previously, a transcription factor (TF) RNAi screen was conducted to identify potential activators that are required to induce gst-4 expression in brap-2(ok1492) mutants. The lipid metabolism regulator NHR-49/HNF4 was among 18 TFs identified. Here, we show that knockdown of nhr-49 suppresses the activation of gst-4 caused by brap-2 inactivation and that gain-of-function alleles of nhr-49 promote gst-4 expression. We also demonstrate that nhr-49 and its cofactor mdt-15 are required to express phase II detoxification enzymes upon exposure to chemicals that induce oxidative stress. Furthermore, we show that NHR-49 and MDT-15 enhance expression of skn-1a/c. These findings identify a novel role for NHR-49 in ROS detoxification by regulating expression of SKN-1C and phase II detoxification genes.
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29
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Redox Signaling of NADPH Oxidases Regulates Oxidative Stress Responses, Immunity and Aging. Antioxidants (Basel) 2018; 7:antiox7100130. [PMID: 30274229 PMCID: PMC6210377 DOI: 10.3390/antiox7100130] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2018] [Revised: 09/25/2018] [Accepted: 09/26/2018] [Indexed: 12/14/2022] Open
Abstract
An accumulating body of evidence suggests that transient or physiological reactive oxygen species (ROS) generated by nicotinamide adenine dinucleotide phosphate (NADPH) oxidases act as a redox signal to re-establish homeostasis. The capacity to re-establish homeostasis progressively declines during aging but is maintained in long-lived animals to promote healthy aging. In the model organism Caenorhabditis elegans, ROS generated by dual oxidases (Duox) are important for extracellular matrix integrity, pathogen defense, oxidative stress resistance, and longevity. The Duox enzymatic activity is tightly regulated and under cellular control. Developmental molting cycles, pathogen infections, toxins, mitochondrial-derived ROS, drugs, and small GTPases (e.g., RHO-1) can activate Duox (BLI-3) to generate ROS, whereas NADPH oxidase inhibitors and negative regulators, such as MEMO-1, can inhibit Duox from generating ROS. Three mechanisms-of-action have been discovered for the Duox/BLI-3-generated ROS: (1) enzymatic activity to catalyze crosslinking of free tyrosine ethyl ester in collagen bundles to stabilize extracellular matrices, (2) high ROS bursts/levels to kill pathogens, and (3) redox signaling activating downstream kinase cascades to transcription factors orchestrating oxidative stress and immunity responses to re-establish homeostasis. Although Duox function at the cell surface is well established, recent genetic and biochemical data also suggests a novel role for Duoxs at the endoplasmic reticulum membrane to control redox signaling. Evidence underlying these mechanisms initiated by ROS from NADPH oxidases, and their relevance for human aging, are discussed in this review. Appropriately controlling NADPH oxidase activity for local and physiological redox signaling to maintain cellular homeostasis might be a therapeutic strategy to promote healthy aging.
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30
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Abstract
Motivation New technologies allow for the elaborate measurement of different traits of single cells under genetic perturbations. These interventional data promise to elucidate intra-cellular networks in unprecedented detail and further help to improve treatment of diseases like cancer. However, cell populations can be very heterogeneous. Results We developed a mixture of Nested Effects Models (M&NEM) for single-cell data to simultaneously identify different cellular subpopulations and their corresponding causal networks to explain the heterogeneity in a cell population. For inference, we assign each cell to a network with a certain probability and iteratively update the optimal networks and cell probabilities in an Expectation Maximization scheme. We validate our method in the controlled setting of a simulation study and apply it to three data sets of pooled CRISPR screens generated previously by two novel experimental techniques, namely Crop-Seq and Perturb-Seq. Availability and implementation The mixture Nested Effects Model (M&NEM) is available as the R-package mnem at https://github.com/cbg-ethz/mnem/. Supplementary information Supplementary data are available at Bioinformatics online.
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Affiliation(s)
- Martin Pirkl
- Department of Biosystems Science and Engineering, ETH Zurich, Basel, Switzerland
- SIB Swiss Institute of Bioinformatics, Basel, Switzerland
| | - Niko Beerenwinkel
- Department of Biosystems Science and Engineering, ETH Zurich, Basel, Switzerland
- SIB Swiss Institute of Bioinformatics, Basel, Switzerland
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31
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D'Amora DR, Hu Q, Pizzardi M, Kubiseski TJ. BRAP-2 promotes DNA damage induced germline apoptosis in C. elegans through the regulation of SKN-1 and AKT-1. Cell Death Differ 2018; 25:1276-1288. [PMID: 29358669 PMCID: PMC6030105 DOI: 10.1038/s41418-017-0038-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Accepted: 11/08/2017] [Indexed: 12/19/2022] Open
Abstract
As part of the DNA damage response (DDR) network, the tumour suppressor Breast cancer susceptibility gene 1 (BRCA1) is activated to facilitate DNA repair, transcription and cell cycle control. BRC-1, the Caenorhabditis elegans ortholog of BRCA1, has conserved function in DNA double strand break repair, wherein a loss of brc-1 results in high levels of germline apoptosis. BRAP2/IMP was initially identified as a BRCA1 associated binding protein and previously we have shown that the C. elegans brap-2 deletion mutant experiences BRC-1 dependent larval arrest when exposed to low concentrations of paraquat. Since BRC-1 function in the germline is conserved, we wanted to determine the role of BRAP-2 in DNA damage induced germline apoptosis in C. elegans. We examined levels of germ cell death following DNA damage and found that brap-2(ok1492) mutants display reduced levels of germline apoptosis when compared to the wild type, and the loss of brap-2 significantly reduced germ cell death in brc-1 mutant animals. We also found increased mRNA levels of skn-1 following DNA damage in brap-2 mutants and that skn-1 RNAi knockdown in brap-2;brc-1 double mutants and a loss of pmk-1 mutation in brap-2 mutants increased apoptosis to wild type levels, indicating that brap-2 promotion of cell survival requires PMK-1 and SKN-1. Since mammalian BRAP2 has been shown to bind the AKT phosphatase PHLPP1/2, it suggests that BRAP2 could be involved in the Insulin/Insulin-like growth factor Signaling (IIS) pathway. We found that this interaction is conserved between the C. elegans homologs and that a loss of akt-1 in brap-2 mutants increased germline apoptosis. Thus in response to DNA damage, our findings suggest that BRAP-2 is required to attenuate the pro-cell survival signals of AKT-1 and PMK-1/SKN-1 to promote DNA damage induced germline apoptosis.
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Affiliation(s)
- Dayana R D'Amora
- Department of Biology, York University, Toronto, Ontario, Canada
| | - Queenie Hu
- Department of Biology, York University, Toronto, Ontario, Canada
- Sunnybrook Research Institute, Toronto, Ontario, Canada
| | - Monica Pizzardi
- Department of Biology, York University, Toronto, Ontario, Canada
| | - Terrance J Kubiseski
- Department of Biology, York University, Toronto, Ontario, Canada.
- Program in Neuroscience, York University, Toronto, Ontario, Canada.
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32
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Construction of Arabidopsis Transcription Factor ORFeome Collections and Identification of Protein-DNA Interactions by High-Throughput Yeast One-Hybrid Screens. Methods Mol Biol 2018; 1794:151-182. [PMID: 29855956 DOI: 10.1007/978-1-4939-7871-7_10] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Identification of transcription factor (TF)-promoter interactions is key to understanding the basic molecular underpinnings of gene regulation. The complexity of gene regulation, however, is driven by the combined function of several TFs recruited to the promoter region, which often confounds the discovery of transcriptional regulatory mechanisms. Genome sequencing enabled the construction of TF-specific ORFeome clone collections that can be used to study TF function with unprecedented coverage. Among the recently developed methods, gene-centered yeast one-hybrid (Y1H) screens performed with these ORFeome collections provide a simple and reliable strategy to identify TF-promoter interactions. Here, we describe high-throughput cloning protocols used to generate a gold standard TF ORFeome collection for the model organism Arabidopsis thaliana. Furthermore, we outline the protocol to build a daughter clone collection suitable for the Y1H assay and a high-throughput Y1H screening procedure that enables rapid assessment of thousands TF-promoter interactions using a robotic platform. These protocols can be universally adopted to build ORFeome libraries and thus expand the usage of gene-centered Y1H screens or other alternative strategies for discovery and characterization of TF functions.
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33
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Telonis AG, Rigoutsos I. Race Disparities in the Contribution of miRNA Isoforms and tRNA-Derived Fragments to Triple-Negative Breast Cancer. Cancer Res 2017; 78:1140-1154. [PMID: 29229607 DOI: 10.1158/0008-5472.can-17-1947] [Citation(s) in RCA: 83] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 10/19/2017] [Accepted: 11/30/2017] [Indexed: 12/14/2022]
Abstract
Triple-negative breast cancer (TNBC) is a breast cancer subtype characterized by marked differences between White and Black/African-American women. We performed a systems-level analysis on datasets from The Cancer Genome Atlas to elucidate how the expression patterns of mRNAs are shaped by regulatory noncoding RNAs (ncRNA). Specifically, we studied isomiRs, that is, isoforms of miRNAs, and tRNA-derived fragments (tRF). In normal breast tissue, we observed a marked cohesiveness in both the ncRNA and mRNA layers and the associations between them. This cohesiveness was widely disrupted in TNBC. Many mRNAs become either differentially expressed or differentially wired between normal breast and TNBC in tandem with isomiR or tRF dysregulation. The affected pathways included energy metabolism, cell signaling, and immune responses. Within TNBC, the wiring of the affected pathways with isomiRs and tRFs differed in each race. Multiple isomiRs and tRFs arising from specific miRNA loci (e.g., miR-200c, miR-21, the miR-17/92 cluster, the miR-183/96/182 cluster) and from specific tRNA loci (e.g., the nuclear tRNAGly and tRNALeu, the mitochondrial tRNAVal and tRNAPro) were strongly associated with the observed race disparities in TNBC. We highlight the race-specific aspects of transcriptome wiring by discussing in detail the metastasis-related MAPK and the Wnt/β-catenin signaling pathways, two of the many key pathways that were found differentially wired. In conclusion, by employing a data- and knowledge-driven approach, we comprehensively analyzed the normal and cancer transcriptomes to uncover novel key contributors to the race-based disparities of TNBC.Significance: This big data-driven study comparing normal and cancer transcriptomes uncovers RNA expression differences between Caucasian and African-American patients with triple-negative breast cancer that might help explain disparities in incidence and aggressive character. Cancer Res; 78(5); 1140-54. ©2017 AACR.
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Affiliation(s)
- Aristeidis G Telonis
- Computational Medicine Center, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania.
| | - Isidore Rigoutsos
- Computational Medicine Center, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania.
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The MXL-3/SBP-1 Axis Is Responsible for Glucose-Dependent Fat Accumulation in C. elegans. Genes (Basel) 2017; 8:genes8110307. [PMID: 29113111 PMCID: PMC5704220 DOI: 10.3390/genes8110307] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Revised: 10/31/2017] [Accepted: 10/31/2017] [Indexed: 12/26/2022] Open
Abstract
Chronic exposure to elevated glucose levels leads to fatty acid accumulation, which promotes the development of metabolic diseases such as obesity and type 2 diabetes. MXL-3 is a conserved transcriptional factor that modulates the inhibition of lipolysis in Caenorhabditis elegans. However, the role of MXL-3 in lipid metabolism during nutrient excess remains unknown. We hypothesized that inhibition of MXL-3 prevents glucose-dependent fat accumulation. Nematodes from wild-type N2, MXL-3::GFP and sbp-1 or mxl-3 null strains were grown on standard, high glucose or high glucose plus metformin plates for 24 h. Using laser-scanning confocal microscopy, we monitored the glucose-induced activation of MXL-3 labeled with GFP (MXL-3::GFP). Lipid levels were determined by Oil Red O (ORO) staining and gas chromatography/mass spectrometry, and gene expression was assessed by qRT-PCR. We found that high glucose activated MXL-3 by increasing its rate of nuclear entry, which in turn increased lipid levels via sterol regulatory element-binding protein (SBP-1). This activated critical genes that synthesize long chain unsaturated fatty acids (MUFAs and PUFAs) and repress lipolytic genes. Interestingly, the anti-diabetic drug metformin inhibited MXL-3 activation and subsequently prevented glucose-dependent fat accumulation. These findings highlight the importance of the MXL-3/SBP-1 axis in the regulation of lipid metabolism during nutritional excess and provide new insight into the mechanism by which metformin prevents lipid accumulation. This study also suggests that inhibition of MXL-3 may serve as a potential target for the treatment of chronic metabolic diseases, including obesity, type 2 diabetes, and cardiovascular disease.
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35
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Wilkinson AC, Nakauchi H, Göttgens B. Mammalian Transcription Factor Networks: Recent Advances in Interrogating Biological Complexity. Cell Syst 2017; 5:319-331. [PMID: 29073372 PMCID: PMC5928788 DOI: 10.1016/j.cels.2017.07.004] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Revised: 06/29/2017] [Accepted: 07/20/2017] [Indexed: 12/11/2022]
Abstract
Transcription factor (TF) networks are a key determinant of cell fate decisions in mammalian development and adult tissue homeostasis and are frequently corrupted in disease. However, our inability to experimentally resolve and interrogate the complexity of mammalian TF networks has hampered the progress in this field. Recent technological advances, in particular large-scale genome-wide approaches, single-cell methodologies, live-cell imaging, and genome editing, are emerging as important technologies in TF network biology. Several recent studies even suggest a need to re-evaluate established models of mammalian TF networks. Here, we provide a brief overview of current and emerging methods to define mammalian TF networks. We also discuss how these emerging technologies facilitate new ways to interrogate complex TF networks, consider the current open questions in the field, and comment on potential future directions and biomedical applications.
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Affiliation(s)
- Adam C Wilkinson
- Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, 265 Campus Drive, Stanford, CA 94305, USA
| | - Hiromitsu Nakauchi
- Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, 265 Campus Drive, Stanford, CA 94305, USA; Division of Stem Cell Therapy, Center for Stem Cell Biology and Regenerative Medicine, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639, Japan
| | - Berthold Göttgens
- Department of Haematology, Cambridge Institute for Medical Research and Wellcome Trust and MRC Cambridge Stem Cell Institute, University of Cambridge, Cambridge CB2 0XY, UK.
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36
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Mori A, Holdorf AD, Walhout AJM. Many transcription factors contribute to C. elegans growth and fat storage. Genes Cells 2017; 22:770-784. [PMID: 28791781 DOI: 10.1111/gtc.12516] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Accepted: 06/10/2017] [Indexed: 12/17/2022]
Abstract
Reverse genetic screens by RNA interference (RNAi) in model organisms such as the nematode Caenorhabditis elegans have provided numerous insights into gene function, thereby connecting genotype to phenotype. However, genes that contribute only subtly are often missed because relatively large numbers of measurements and reliable quantification are required to overcome experimental and biological noise that may mask subtle phenotypic effects. Here, we address this challenge by focusing on two phenotypes in C. elegans: growth and fat storage. We carried out comprehensive RNAi knockdown of transcription factors (TFs), as these are known important regulators of biological processes during development and the maintenance of homeostasis. Microscopy images of TF knockdown animals stained with Oil Red O (ORO) were captured, and body size (proxy for growth) and ORO staining intensity (proxy for fat storage) were precisely quantified using a newly developed imaging tool we named IPPOME (Image Processing for Precise and Objective MEasurement). We found that a surprisingly large proportion of TFs contribute to growth and fat storage, but that most TFs have only subtle, yet significant effects. This study provides a blueprint for studies of other genes and phenotypes in C. elegans.
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Affiliation(s)
- Akihiro Mori
- Program in Systems Biology, Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, 01605, USA
| | - Amy D Holdorf
- Program in Systems Biology, Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, 01605, USA
| | - Albertha J M Walhout
- Program in Systems Biology, Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, 01605, USA
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The Oxidative Stress Response in Caenorhabditis elegans Requires the GATA Transcription Factor ELT-3 and SKN-1/Nrf2. Genetics 2017; 206:1909-1922. [PMID: 28600327 DOI: 10.1534/genetics.116.198788] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Accepted: 06/02/2017] [Indexed: 12/19/2022] Open
Abstract
Cellular damage caused by reactive oxygen species is believed to be a major contributor to age-associated diseases. Previously, we characterized the Caenorhabditis elegans Brap2 ortholog (BRAP-2) and found that it is required to prevent larval arrest in response to elevated levels of oxidative stress. Here, we report that C. elegans brap-2 mutants display increased expression of SKN-1-dependent, phase II detoxification enzymes that is dependent on PMK-1 (a p38 MAPK C. elegans ortholog). An RNA-interference screen was conducted using a transcription factor library to identify genes required for increased expression of the SKN-1 target gst-4 in brap-2 mutants. We identified ELT-3, a member of the GATA transcription factor family, as a positive regulator of gst-4p::gfp expression. We found that ELT-3 interacts with SKN-1 to activate gst-4 transcription in vitro and that elt-3 is required for enhanced gst-4 expression in the brap-2(ok1492) mutant in vivo Furthermore, nematodes overexpressing SKN-1 required ELT-3 for life-span extension. Taken together, these results suggest a model where BRAP-2 acts as negative regulator of SKN-1 through inhibition of p38 MAPK activity, and that the GATA transcription factor ELT-3 is required along with SKN-1 for the phase II detoxification response in C. elegans.
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38
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Tamburino AM, Kaymak E, Shrestha S, Holdorf AD, Ryder SP, Walhout AJM. PRIMA: a gene-centered, RNA-to-protein method for mapping RNA-protein interactions. ACTA ACUST UNITED AC 2017; 5:e1295130. [PMID: 28702278 DOI: 10.1080/21690731.2017.1295130] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Revised: 01/23/2017] [Accepted: 02/09/2017] [Indexed: 12/20/2022]
Abstract
Interactions between RNA binding proteins (RBPs) and mRNAs are critical to post-transcriptional gene regulation. Eukaryotic genomes encode thousands of mRNAs and hundreds of RBPs. However, in contrast to interactions between transcription factors (TFs) and DNA, the interactome between RBPs and RNA has been explored for only a small number of proteins and RNAs. This is largely because the focus has been on using 'protein-centered' (RBP-to-RNA) interaction mapping methods that identify the RNAs with which an individual RBP interacts. While powerful, these methods cannot as of yet be applied to the entire RBPome. Moreover, it may be desirable for a researcher to identify the repertoire of RBPs that can interact with an mRNA of interest-in a 'gene-centered' manner-yet few such techniques are available. Here, we present Protein-RNA Interaction Mapping Assay (PRIMA) with which an RNA 'bait' can be tested versus multiple RBP 'preys' in a single experiment. PRIMA is a translation-based assay that examines interactions in the yeast cytoplasm, the cellular location of mRNA translation. We show that PRIMA can be used with small RNA elements, as well as with full-length Caenorhabditis elegans 3' UTRs. PRIMA faithfully recapitulated numerous well-characterized RNA-RBP interactions and also identified novel interactions, some of which were confirmed in vivo. We envision that PRIMA will provide a complementary tool to expand the depth and scale with which the RNA-RBP interactome can be explored.
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Affiliation(s)
- Alex M Tamburino
- Program in Systems Biology and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Ebru Kaymak
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA, USA
| | - Shaleen Shrestha
- Program in Systems Biology and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Amy D Holdorf
- Program in Systems Biology and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Sean P Ryder
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA, USA
| | - Albertha J M Walhout
- Program in Systems Biology and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA
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39
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Zhang J, Holdorf AD, Walhout AJ. C. elegans and its bacterial diet as a model for systems-level understanding of host-microbiota interactions. Curr Opin Biotechnol 2017; 46:74-80. [PMID: 28189107 PMCID: PMC5544573 DOI: 10.1016/j.copbio.2017.01.008] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Revised: 01/19/2017] [Accepted: 01/20/2017] [Indexed: 02/06/2023]
Abstract
Resident microbes of the human body, particularly the gut microbiota, provide essential functions for the host, and, therefore, have important roles in human health as well as mitigating disease. It is difficult to study the mechanisms by which the microbiota affect human health, especially at a systems-level, due to heterogeneity of human genomes, the complexity and heterogeneity of the gut microbiota, the challenge of growing these bacteria in the laboratory, and the lack of bacterial genetics in most microbiotal species. In the last few years, the interspecies model of the nematode Caenorhabditis elegans and its bacterial diet has proven powerful for studying host-microbiota interactions, as both the animal and its bacterial diet can be subjected to large-scale and high-throughput genetic screening. The high level of homology between many C. elegans and human genes, as well as extensive similarities between human and C. elegans metabolism, indicates that the findings obtained from this interspecies model may be broadly relevant to understanding how the human microbiota affects physiology and disease. In this review, we summarize recent systems studies on how bacteria interact with C. elegans and affect life history traits.
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Affiliation(s)
- Jingyan Zhang
- Program in Systems Biology and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Amy D Holdorf
- Program in Systems Biology and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Albertha Jm Walhout
- Program in Systems Biology and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA.
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40
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Sparks EE, Drapek C, Gaudinier A, Li S, Ansariola M, Shen N, Hennacy JH, Zhang J, Turco G, Petricka JJ, Foret J, Hartemink AJ, Gordân R, Megraw M, Brady SM, Benfey PN. Establishment of Expression in the SHORTROOT-SCARECROW Transcriptional Cascade through Opposing Activities of Both Activators and Repressors. Dev Cell 2016; 39:585-596. [PMID: 27923776 DOI: 10.1016/j.devcel.2016.09.031] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Revised: 05/27/2016] [Accepted: 09/29/2016] [Indexed: 12/28/2022]
Abstract
Tissue-specific gene expression is often thought to arise from spatially restricted transcriptional cascades. However, it is unclear how expression is established at the top of these cascades in the absence of pre-existing specificity. We generated a transcriptional network to explore how transcription factor expression is established in the Arabidopsis thaliana root ground tissue. Regulators of the SHORTROOT-SCARECROW transcriptional cascade were validated in planta. At the top of this cascade, we identified both activators and repressors of SHORTROOT. The aggregate spatial expression of these regulators is not sufficient to predict transcriptional specificity. Instead, modeling, transcriptional reporters, and synthetic promoters support a mechanism whereby expression at the top of the SHORTROOT-SCARECROW cascade is established through opposing activities of activators and repressors.
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Affiliation(s)
- Erin E Sparks
- Department of Biology, Duke University, Durham, NC 27708, USA
| | - Colleen Drapek
- Department of Biology, Duke University, Durham, NC 27708, USA
| | - Allison Gaudinier
- Department of Plant Biology and Genome Center, University of California Davis, Davis, CA 95616, USA
| | - Song Li
- Department of Crop and Soil Environmental Sciences, Virginia Tech, Blacksburg, VA 24061, USA
| | - Mitra Ansariola
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR 97331, USA
| | - Ning Shen
- Department of Pharmacology and Cancer Biology, Duke University, Durham, NC 27710, USA; Center for Genomic and Computational Biology, Duke University, Durham, NC 27708, USA
| | | | - Jingyuan Zhang
- Department of Biology, Duke University, Durham, NC 27708, USA
| | - Gina Turco
- Department of Plant Biology and Genome Center, University of California Davis, Davis, CA 95616, USA
| | | | - Jessica Foret
- Department of Plant Biology and Genome Center, University of California Davis, Davis, CA 95616, USA
| | - Alexander J Hartemink
- Department of Biology, Duke University, Durham, NC 27708, USA; Center for Genomic and Computational Biology, Duke University, Durham, NC 27708, USA; Department of Computer Science, Duke University, Durham, NC 27708, USA
| | - Raluca Gordân
- Center for Genomic and Computational Biology, Duke University, Durham, NC 27708, USA; Department of Computer Science, Duke University, Durham, NC 27708, USA; Department of Biostatistics and Bioinformatics, Duke University, Durham, NC 27710, USA
| | - Molly Megraw
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR 97331, USA
| | - Siobhan M Brady
- Department of Plant Biology and Genome Center, University of California Davis, Davis, CA 95616, USA
| | - Philip N Benfey
- Department of Biology, Duke University, Durham, NC 27708, USA; Howard Hughes Medical Institute, Duke University, Durham, NC 27708, USA.
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41
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Fuxman Bass JI, Pons C, Kozlowski L, Reece-Hoyes JS, Shrestha S, Holdorf AD, Mori A, Myers CL, Walhout AJ. A gene-centered C. elegans protein-DNA interaction network provides a framework for functional predictions. Mol Syst Biol 2016; 12:884. [PMID: 27777270 PMCID: PMC5081483 DOI: 10.15252/msb.20167131] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Transcription factors (TFs) play a central role in controlling spatiotemporal gene expression and the response to environmental cues. A comprehensive understanding of gene regulation requires integrating physical protein–DNA interactions (PDIs) with TF regulatory activity, expression patterns, and phenotypic data. Although great progress has been made in mapping PDIs using chromatin immunoprecipitation, these studies have only characterized ~10% of TFs in any metazoan species. The nematode C. elegans has been widely used to study gene regulation due to its compact genome with short regulatory sequences. Here, we delineated the largest gene‐centered metazoan PDI network to date by examining interactions between 90% of C. elegans TFs and 15% of gene promoters. We used this network as a backbone to predict TF binding sites for 77 TFs, two‐thirds of which are novel, as well as integrate gene expression, protein–protein interaction, and phenotypic data to predict regulatory and biological functions for multiple genes and TFs.
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Affiliation(s)
- Juan I Fuxman Bass
- Program in Systems Biology and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Carles Pons
- Department of Computer Science and Engineering, University of Minnesota-Twin Cities, Minneapolis, MN, USA
| | - Lucie Kozlowski
- Program in Systems Biology and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - John S Reece-Hoyes
- Program in Systems Biology and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Shaleen Shrestha
- Program in Systems Biology and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Amy D Holdorf
- Program in Systems Biology and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Akihiro Mori
- Program in Systems Biology and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Chad L Myers
- Department of Computer Science and Engineering, University of Minnesota-Twin Cities, Minneapolis, MN, USA
| | - Albertha Jm Walhout
- Program in Systems Biology and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA
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42
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Potential Direct Regulators of the Drosophila yellow Gene Identified by Yeast One-Hybrid and RNAi Screens. G3-GENES GENOMES GENETICS 2016; 6:3419-3430. [PMID: 27527791 PMCID: PMC5068961 DOI: 10.1534/g3.116.032607] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The regulation of gene expression controls development, and changes in this regulation often contribute to phenotypic evolution. Drosophila pigmentation is a model system for studying evolutionary changes in gene regulation, with differences in expression of pigmentation genes such as yellow that correlate with divergent pigment patterns among species shown to be caused by changes in cis- and trans-regulation. Currently, much more is known about the cis-regulatory component of divergent yellow expression than the trans-regulatory component, in part because very few trans-acting regulators of yellow expression have been identified. This study aims to improve our understanding of the trans-acting control of yellow expression by combining yeast-one-hybrid and RNAi screens for transcription factors binding to yellow cis-regulatory sequences and affecting abdominal pigmentation in adults, respectively. Of the 670 transcription factors included in the yeast-one-hybrid screen, 45 showed evidence of binding to one or more sequence fragments tested from the 5′ intergenic and intronic yellow sequences from D. melanogaster, D. pseudoobscura, and D. willistoni, suggesting that they might be direct regulators of yellow expression. Of the 670 transcription factors included in the yeast-one-hybrid screen, plus another TF previously shown to be genetically upstream of yellow, 125 were also tested using RNAi, and 32 showed altered abdominal pigmentation. Nine transcription factors were identified in both screens, including four nuclear receptors related to ecdysone signaling (Hr78, Hr38, Hr46, and Eip78C). This finding suggests that yellow expression might be directly controlled by nuclear receptors influenced by ecdysone during early pupal development when adult pigmentation is forming.
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43
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Multi-level regulation of cellular glycosylation: from genes to transcript to enzyme to structure. Curr Opin Struct Biol 2016; 40:145-152. [PMID: 27744149 DOI: 10.1016/j.sbi.2016.09.013] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Revised: 08/08/2016] [Accepted: 09/27/2016] [Indexed: 12/29/2022]
Abstract
Glycosylation is a ubiquitous mammalian post-translational modification that both decorates a majority of expressed proteins and regulates their function. Cellular glycan biosynthesis is facilitated by a few hundred enzymes that are collectively termed 'glycoenzymes'. The expression and activity of these enzymes is controlled at the transcription, translation and post-translation levels. New wet-lab advances are providing analytical methods to collect large-scale data at these multiple levels, relational databases are starting to collate these results, and computer models are beginning to integrate this information across scales in order to gain new knowledge. These activities are likely to enable the qualitative and quantitative mapping of pathways regulating glycan production and function in proteins, cells and tissue.
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44
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Blitz IL, Paraiso KD, Patrushev I, Chiu WTY, Cho KWY, Gilchrist MJ. A catalog of Xenopus tropicalis transcription factors and their regional expression in the early gastrula stage embryo. Dev Biol 2016; 426:409-417. [PMID: 27475627 PMCID: PMC5596316 DOI: 10.1016/j.ydbio.2016.07.002] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 07/01/2016] [Accepted: 07/01/2016] [Indexed: 12/30/2022]
Abstract
Gene regulatory networks (GRNs) involve highly combinatorial interactions between transcription factors and short sequence motifs in cis-regulatory modules of target genes to control cellular phenotypes. The GRNs specifying most cell types are largely unknown and are the subject of wide interest. A catalog of transcription factors is a valuable tool toward obtaining a deeper understanding of the role of these critical effectors in any biological setting. Here we present a comprehensive catalog of the transcription factors for the diploid frog Xenopus tropicalis. We identify 1235 genes encoding DNA-binding transcription factors, comparable to the numbers found in typical mammalian species. In detail, the repertoire of X. tropicalis transcription factor genes is nearly identical to human and mouse, with the exception of zinc finger family members, and a small number of species/lineage-specific gene duplications and losses relative to the mammalian repertoires. We applied this resource to the identification of transcription factors differentially expressed in the early gastrula stage embryo. We find transcription factor enrichment in Spemann's organizer, the ventral mesoderm, ectoderm and endoderm, and report 218 TFs that show regionalized expression patterns at this stage. Many of these have not been previously reported as expressed in the early embryo, suggesting thus far unappreciated roles for many transcription factors in the GRNs regulating early development. We expect our transcription factor catalog will facilitate myriad studies using Xenopus as a model system to understand basic biology and human disease.
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Affiliation(s)
- Ira L Blitz
- Department of Developmental and Cell Biology, University of California, Irvine, CA 92697, United States.
| | - Kitt D Paraiso
- Department of Developmental and Cell Biology, University of California, Irvine, CA 92697, United States
| | - Ilya Patrushev
- The Francis Crick Institute, Mill Hill Laboratory, The Ridgeway Mill Hill, London NW7 1AA, UK
| | - William T Y Chiu
- Department of Developmental and Cell Biology, University of California, Irvine, CA 92697, United States
| | - Ken W Y Cho
- Department of Developmental and Cell Biology, University of California, Irvine, CA 92697, United States.
| | - Michael J Gilchrist
- The Francis Crick Institute, Mill Hill Laboratory, The Ridgeway Mill Hill, London NW7 1AA, UK.
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45
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Watson E, Olin-Sandoval V, Hoy MJ, Li CH, Louisse T, Yao V, Mori A, Holdorf AD, Troyanskaya OG, Ralser M, Walhout AJ. Metabolic network rewiring of propionate flux compensates vitamin B12 deficiency in C. elegans. eLife 2016; 5. [PMID: 27383050 PMCID: PMC4951191 DOI: 10.7554/elife.17670] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Accepted: 06/20/2016] [Indexed: 12/20/2022] Open
Abstract
Metabolic network rewiring is the rerouting of metabolism through the use of alternate enzymes to adjust pathway flux and accomplish specific anabolic or catabolic objectives. Here, we report the first characterization of two parallel pathways for the breakdown of the short chain fatty acid propionate in Caenorhabditis elegans. Using genetic interaction mapping, gene co-expression analysis, pathway intermediate quantification and carbon tracing, we uncover a vitamin B12-independent propionate breakdown shunt that is transcriptionally activated on vitamin B12 deficient diets, or under genetic conditions mimicking the human diseases propionic- and methylmalonic acidemia, in which the canonical B12-dependent propionate breakdown pathway is blocked. Our study presents the first example of transcriptional vitamin-directed metabolic network rewiring to promote survival under vitamin deficiency. The ability to reroute propionate breakdown according to B12 availability may provide C. elegans with metabolic plasticity and thus a selective advantage on different diets in the wild.
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Affiliation(s)
- Emma Watson
- Program in Systems Biology, University of Massachusetts Medical School, Worcester, United States.,Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, United States
| | | | - Michael J Hoy
- Program in Systems Biology, University of Massachusetts Medical School, Worcester, United States.,Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, United States
| | - Chi-Hua Li
- Program in Systems Biology, University of Massachusetts Medical School, Worcester, United States.,Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, United States
| | - Timo Louisse
- Program in Systems Biology, University of Massachusetts Medical School, Worcester, United States.,Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, United States
| | - Victoria Yao
- Department of Computer Science, Princeton University, Princeton, United States.,Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, United States
| | - Akihiro Mori
- Program in Systems Biology, University of Massachusetts Medical School, Worcester, United States.,Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, United States
| | - Amy D Holdorf
- Program in Systems Biology, University of Massachusetts Medical School, Worcester, United States.,Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, United States
| | - Olga G Troyanskaya
- Department of Computer Science, Princeton University, Princeton, United States.,Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, United States.,Simons Center for Data Analysis, Simons Foundation, New York, United States
| | - Markus Ralser
- Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom.,The Francis Crick Institute, Mill Hill Laboratory, London, United Kingdom
| | - Albertha Jm Walhout
- Program in Systems Biology, University of Massachusetts Medical School, Worcester, United States.,Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, United States
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46
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Moffa G, Erdmann G, Voloshanenko O, Hundsrucker C, Sadeh MJ, Boutros M, Spang R. Refining Pathways: A Model Comparison Approach. PLoS One 2016; 11:e0155999. [PMID: 27248690 PMCID: PMC4889067 DOI: 10.1371/journal.pone.0155999] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Accepted: 05/06/2016] [Indexed: 11/30/2022] Open
Abstract
Cellular signalling pathways consolidate multiple molecular interactions into working models of signal propagation, amplification, and modulation. They are described and visualized as networks. Adjusting network topologies to experimental data is a key goal of systems biology. While network reconstruction algorithms like nested effects models are well established tools of computational biology, their data requirements can be prohibitive for their practical use. In this paper we suggest focussing on well defined aspects of a pathway and develop the computational tools to do so. We adapt the framework of nested effect models to focus on a specific aspect of activated Wnt signalling in HCT116 colon cancer cells: Does the activation of Wnt target genes depend on the secretion of Wnt ligands or do mutations in the signalling molecule β-catenin make this activation independent from them? We framed this question into two competing classes of models: Models that depend on Wnt ligands secretion versus those that do not. The model classes translate into restrictions of the pathways in the network topology. Wnt dependent models are more flexible than Wnt independent models. Bayes factors are the standard Bayesian tool to compare different models fairly on the data evidence. In our analysis, the Bayes factors depend on the number of potential Wnt signalling target genes included in the models. Stability analysis with respect to this number showed that the data strongly favours Wnt ligands dependent models for all realistic numbers of target genes.
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Affiliation(s)
- Giusi Moffa
- Department of Statistical Bioinformatics, Institute of Functional Genomics, University of Regensburg, Regensburg, Germany
| | - Gerrit Erdmann
- Division of Signaling and Functional Genomics, German Cancer Research Center (DKFZ) and Department of Cell and Molecular Biology, Faculty of Medicine Mannheim, Heidelberg University, Heidelberg, Germany
| | - Oksana Voloshanenko
- Division of Signaling and Functional Genomics, German Cancer Research Center (DKFZ) and Department of Cell and Molecular Biology, Faculty of Medicine Mannheim, Heidelberg University, Heidelberg, Germany
| | - Christian Hundsrucker
- Department of Statistical Bioinformatics, Institute of Functional Genomics, University of Regensburg, Regensburg, Germany
| | - Mohammad J. Sadeh
- Department of Statistical Bioinformatics, Institute of Functional Genomics, University of Regensburg, Regensburg, Germany
| | - Michael Boutros
- Division of Signaling and Functional Genomics, German Cancer Research Center (DKFZ) and Department of Cell and Molecular Biology, Faculty of Medicine Mannheim, Heidelberg University, Heidelberg, Germany
| | - Rainer Spang
- Department of Statistical Bioinformatics, Institute of Functional Genomics, University of Regensburg, Regensburg, Germany
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47
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Zugasti O, Thakur N, Belougne J, Squiban B, Kurz CL, Soulé J, Omi S, Tichit L, Pujol N, Ewbank JJ. A quantitative genome-wide RNAi screen in C. elegans for antifungal innate immunity genes. BMC Biol 2016; 14:35. [PMID: 27129311 PMCID: PMC4850687 DOI: 10.1186/s12915-016-0256-3] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Accepted: 04/18/2016] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND Caenorhabditis elegans has emerged over the last decade as a useful model for the study of innate immunity. Its infection with the pathogenic fungus Drechmeria coniospora leads to the rapid up-regulation in the epidermis of genes encoding antimicrobial peptides. The molecular basis of antimicrobial peptide gene regulation has been previously characterized through forward genetic screens. Reverse genetics, based on RNAi, provide a complementary approach to dissect the worm's immune defenses. RESULTS We report here the full results of a quantitative whole-genome RNAi screen in C. elegans for genes involved in regulating antimicrobial peptide gene expression. The results will be a valuable resource for those contemplating similar RNAi-based screens and also reveal the limitations of such an approach. We present several strategies, including a comprehensive class clustering method, to overcome these limitations and which allowed us to characterize the different steps of the interaction between C. elegans and the fungus D. coniospora, leading to a complete description of the MAPK pathway central to innate immunity in C. elegans. The results further revealed a cross-tissue signaling, triggered by mitochondrial dysfunction in the intestine, that suppresses antimicrobial peptide gene expression in the nematode epidermis. CONCLUSIONS Overall, our results provide an unprecedented system's level insight into the regulation of C. elegans innate immunity. They represent a significant contribution to our understanding of host defenses and will lead to a better comprehension of the function and evolution of animal innate immunity.
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Affiliation(s)
- Olivier Zugasti
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université UM2, Inserm, U1104, CNRS UMR7280, 13288, Marseille, France
- Present address: Institut de Biologie du Développement de Marseille, CNRS, UMR6216, Case 907, Marseille, France
| | - Nishant Thakur
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université UM2, Inserm, U1104, CNRS UMR7280, 13288, Marseille, France
| | - Jérôme Belougne
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université UM2, Inserm, U1104, CNRS UMR7280, 13288, Marseille, France
| | - Barbara Squiban
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université UM2, Inserm, U1104, CNRS UMR7280, 13288, Marseille, France
- Present address: Section of Hematology/Oncology, Department of Pediatrics, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - C Léopold Kurz
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université UM2, Inserm, U1104, CNRS UMR7280, 13288, Marseille, France
- Present address: Institut de Biologie du Développement de Marseille, CNRS, UMR6216, Case 907, Marseille, France
| | - Julien Soulé
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université UM2, Inserm, U1104, CNRS UMR7280, 13288, Marseille, France
- Present address: Institut de Genomique Fonctionnelle, 141, rue de la Cardonille, 34094, Montpellier Cedex 05, France
| | - Shizue Omi
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université UM2, Inserm, U1104, CNRS UMR7280, 13288, Marseille, France
| | - Laurent Tichit
- Institut de Mathématiques de Marseille, Aix Marseille Université, I2M Centrale Marseille, CNRS UMR 7373, 13453, Marseille, France
| | - Nathalie Pujol
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université UM2, Inserm, U1104, CNRS UMR7280, 13288, Marseille, France.
| | - Jonathan J Ewbank
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université UM2, Inserm, U1104, CNRS UMR7280, 13288, Marseille, France.
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Chen JC, Cerise JE, Jabbari A, Clynes R, Christiano AM. Master regulators of infiltrate recruitment in autoimmune disease identified through network-based molecular deconvolution. Cell Syst 2015; 1:326-337. [PMID: 26665180 DOI: 10.1016/j.cels.2015.11.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Network-based molecular modeling of physiological behaviors has proven invaluable in the study of complex diseases such as cancer, but these approaches remain largely untested in contexts involving interacting tissues such as autoimmunity. Here, using Alopecia Areata (AA) as a model, we have adapted regulatory network analysis to specifically isolate physiological behaviors in the skin that contribute to the recruitment of immune cells in autoimmune disease. We use context-specific regulatory networks to deconvolve and identify skin-specific regulatory modules with IKZF1 and DLX4 as master regulators (MRs). These MRs are sufficient to induce AA-like molecular states in vitro in three cultured cell lines, resulting in induced NKG2D-dependent cytotoxicity. This work demonstrates the feasibility of a network-based approach for compartmentalizing and targeting molecular behaviors contributing to interactions between tissues in autoimmune disease.
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Affiliation(s)
- James C Chen
- Department of Dermatology, Herbert Irving Pavilion, Columbia University, 161 Fort Washington Avenue, New York, NY, 10032, USA ; Department of Systems Biology, Columbia University, 1130 Saint Nicholas Avenue, New York, NY, 10032, USA
| | - Jane E Cerise
- Department of Dermatology, Herbert Irving Pavilion, Columbia University, 161 Fort Washington Avenue, New York, NY, 10032, USA
| | - Ali Jabbari
- Department of Dermatology, Herbert Irving Pavilion, Columbia University, 161 Fort Washington Avenue, New York, NY, 10032, USA
| | - Raphael Clynes
- Department of Dermatology, Herbert Irving Pavilion, Columbia University, 161 Fort Washington Avenue, New York, NY, 10032, USA
| | - Angela M Christiano
- Department of Dermatology, Herbert Irving Pavilion, Columbia University, 161 Fort Washington Avenue, New York, NY, 10032, USA ; Department of Genetics and Development, Columbia University, 701 West 168th Street, New York, NY, 10032, USA
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