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Kudron M, Gevirtzman L, Victorsen A, Lear BC, Gao J, Xu J, Samanta S, Frink E, Tran-Pearson A, Huynh C, Vafeados D, Hammonds A, Fisher W, Wall M, Wesseling G, Hernandez V, Lin Z, Kasparian M, White K, Allada R, Gerstein M, Hillier L, Celniker SE, Reinke V, Waterston RH. Binding profiles for 954 Drosophila and C. elegans transcription factors reveal tissue specific regulatory relationships. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.18.576242. [PMID: 38293065 PMCID: PMC10827215 DOI: 10.1101/2024.01.18.576242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2024]
Abstract
A catalog of transcription factor (TF) binding sites in the genome is critical for deciphering regulatory relationships. Here we present the culmination of the modERN (model organism Encyclopedia of Regulatory Networks) consortium that systematically assayed TF binding events in vivo in two major model organisms, Drosophila melanogaster (fly) and Caenorhabditis elegans (worm). We describe key features of these datasets, comprising 604 TFs identifying 3.6M sites in the fly and 350 TFs identifying 0.9 M sites in the worm. Applying a machine learning model to these data identifies sets of TFs with a prominent role in promoting target gene expression in specific cell types. TF binding data are available through the ENCODE Data Coordinating Center and at https://epic.gs.washington.edu/modERNresource, which provides access to processed and summary data, as well as widgets to probe cell type-specific TF-target relationships. These data are a rich resource that should fuel investigations into TF function during development.
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Affiliation(s)
- Michelle Kudron
- Department of Genetics, Yale University, New Haven, Connecticut 06520
| | - Louis Gevirtzman
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, Washington 98195
| | - Alec Victorsen
- Department of Laboratory Medicine & Pathology, University of Minnesota, Minneapolis, MN 55455
| | - Bridget C. Lear
- Department of Neurobiology, Northwestern University, Evanston IL 60208
| | - Jiahao Gao
- Program in Computational Biology and Bioinformatics, Yale University, New Haven, Connecticut 06520
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520
| | - Jinrui Xu
- Department of Biology, Howard University, Washington, District of Columbia 20059, USA
- Center for Applied Data Science and Analytics, Howard University, Washington, District of Columbia 20059, USA
| | - Swapna Samanta
- Department of Genetics, Yale University, New Haven, Connecticut 06520
| | - Emily Frink
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, Washington 98195
| | - Adri Tran-Pearson
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, Washington 98195
| | - Chau Huynh
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, Washington 98195
| | - Dionne Vafeados
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, Washington 98195
| | - Ann Hammonds
- Division of Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, California 94720
| | - William Fisher
- Division of Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, California 94720
| | - Martha Wall
- Institute for Genomics and Systems Biology, Department of Human Genetics, University of Chicago, Illinois 60637
| | - Greg Wesseling
- Department of Neurobiology, Northwestern University, Evanston IL 60208
| | - Vanessa Hernandez
- Department of Neurobiology, Northwestern University, Evanston IL 60208
| | - Zhichun Lin
- Department of Neurobiology, Northwestern University, Evanston IL 60208
| | - Mary Kasparian
- Department of Neurobiology, Northwestern University, Evanston IL 60208
| | - Kevin White
- Department of Biochemistry and Precision Medicine Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597
| | - Ravi Allada
- Department of Neurobiology, Northwestern University, Evanston IL 60208
| | - Mark Gerstein
- Program in Computational Biology and Bioinformatics, Yale University, New Haven, Connecticut 06520
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520
- Department of Statistics and Data Science, Yale University, New Haven, Connecticut 06520, USA
| | - LaDeana Hillier
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, Washington 98195
| | - Susan E. Celniker
- Division of Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, California 94720
| | - Valerie Reinke
- Department of Genetics, Yale University, New Haven, Connecticut 06520
| | - Robert H. Waterston
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, Washington 98195
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2
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Li Y, Chen S, Liu W, Zhao D, Gao Y, Hu S, Liu H, Li Y, Qu L, Liu X. A full-body transcription factor expression atlas with completely resolved cell identities in C. elegans. Nat Commun 2024; 15:358. [PMID: 38195740 PMCID: PMC10776613 DOI: 10.1038/s41467-023-42677-6] [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: 02/23/2023] [Accepted: 10/18/2023] [Indexed: 01/11/2024] Open
Abstract
Invariant cell lineage in C. elegans enables spatiotemporal resolution of transcriptional regulatory mechanisms controlling the fate of each cell. Here, we develop RAPCAT (Robust-point-matching- And Piecewise-affine-based Cell Annotation Tool) to automate cell identity assignment in three-dimensional image stacks of L1 larvae and profile reporter expression of 620 transcription factors in every cell. Transcription factor profile-based clustering analysis defines 80 cell types distinct from conventional phenotypic cell types and identifies three general phenotypic modalities related to these classifications. First, transcription factors are broadly downregulated in quiescent stage Hermaphrodite Specific Neurons, suggesting stage- and cell type-specific variation in transcriptome size. Second, transcription factor expression is more closely associated with morphology than other phenotypic modalities in different pre- and post-differentiation developmental stages. Finally, embryonic cell lineages can be associated with specific transcription factor expression patterns and functions that persist throughout postembryonic life. This study presents a comprehensive transcription factor atlas for investigation of intra-cell type heterogeneity.
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Affiliation(s)
- Yongbin Li
- College of Life Sciences, Capital Normal University, Beijing, 100048, China
| | - Siyu Chen
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Weihong Liu
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
- Intelligent Perception Lab, Hanwang Technology Co., Ltd, Beijing, 100193, China
| | - Di Zhao
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
- Tianjin Key Laboratory of Exercise Physiology and Sports Medicine, Institute of Sport, Exercise & Health, Tianjin University of Sport, Tianjin, 300381, China
| | - Yimeng Gao
- College of Life Sciences, Capital Normal University, Beijing, 100048, China
| | - Shipeng Hu
- College of Life Sciences, Capital Normal University, Beijing, 100048, China
| | - Hanyu Liu
- College of Life Sciences, Capital Normal University, Beijing, 100048, China
| | - Yuanyuan Li
- Ministry of Education Key Laboratory of Intelligent Computation & Signal Processing, Information Materials and Intelligent Sensing Laboratory of Anhui Province, School of Electronics and Information Engineering, Anhui University, Hefei, 230039, China
| | - Lei Qu
- Ministry of Education Key Laboratory of Intelligent Computation & Signal Processing, Information Materials and Intelligent Sensing Laboratory of Anhui Province, School of Electronics and Information Engineering, Anhui University, Hefei, 230039, China
| | - Xiao Liu
- College of Life Sciences, Capital Normal University, Beijing, 100048, China.
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3
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Liu J, Murray JI. Mechanisms of lineage specification in Caenorhabditis elegans. Genetics 2023; 225:iyad174. [PMID: 37847877 DOI: 10.1093/genetics/iyad174] [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: 08/26/2023] [Accepted: 09/18/2023] [Indexed: 10/19/2023] Open
Abstract
The studies of cell fate and lineage specification are fundamental to our understanding of the development of multicellular organisms. Caenorhabditis elegans has been one of the premiere systems for studying cell fate specification mechanisms at single cell resolution, due to its transparent nature, the invariant cell lineage, and fixed number of somatic cells. We discuss the general themes and regulatory mechanisms that have emerged from these studies, with a focus on somatic lineages and cell fates. We next review the key factors and pathways that regulate the specification of discrete cells and lineages during embryogenesis and postembryonic development; we focus on transcription factors and include numerous lineage diagrams that depict the expression of key factors that specify embryonic founder cells and postembryonic blast cells, and the diverse somatic cell fates they generate. We end by discussing some future perspectives in cell and lineage specification.
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Affiliation(s)
- Jun Liu
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA
| | - John Isaac Murray
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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4
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Medwig-Kinney TN, Kinney BA, Martinez MAQ, Yee C, Sirota SS, Mullarkey AA, Somineni N, Hippler J, Zhang W, Shen K, Hammell C, Pani AM, Matus DQ. Dynamic compartmentalization of the pro-invasive transcription factor NHR-67 reveals a role for Groucho in regulating a proliferative-invasive cellular switch in C. elegans. eLife 2023; 12:RP84355. [PMID: 38038410 PMCID: PMC10691804 DOI: 10.7554/elife.84355] [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] [Indexed: 12/02/2023] Open
Abstract
A growing body of evidence suggests that cell division and basement membrane invasion are mutually exclusive cellular behaviors. How cells switch between proliferative and invasive states is not well understood. Here, we investigated this dichotomy in vivo by examining two cell types in the developing Caenorhabditis elegans somatic gonad that derive from equipotent progenitors, but exhibit distinct cell behaviors: the post-mitotic, invasive anchor cell and the neighboring proliferative, non-invasive ventral uterine (VU) cells. We show that the fates of these cells post-specification are more plastic than previously appreciated and that levels of NHR-67 are important for discriminating between invasive and proliferative behavior. Transcription of NHR-67 is downregulated following post-translational degradation of its direct upstream regulator, HLH-2 (E/Daughterless) in VU cells. In the nuclei of VU cells, residual NHR-67 protein is compartmentalized into discrete punctae that are dynamic over the cell cycle and exhibit liquid-like properties. By screening for proteins that colocalize with NHR-67 punctae, we identified new regulators of uterine cell fate maintenance: homologs of the transcriptional co-repressor Groucho (UNC-37 and LSY-22), as well as the TCF/LEF homolog POP-1. We propose a model in which the association of NHR-67 with the Groucho/TCF complex suppresses the default invasive state in non-invasive cells, which complements transcriptional regulation to add robustness to the proliferative-invasive cellular switch in vivo.
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Affiliation(s)
- Taylor N Medwig-Kinney
- Department of Biochemistry and Cell Biology, Stony Brook UniversityStony BrookUnited States
| | - Brian A Kinney
- Cold Spring Harbor LaboratoryCold Spring HarborUnited States
| | - Michael AQ Martinez
- Department of Biochemistry and Cell Biology, Stony Brook UniversityStony BrookUnited States
| | - Callista Yee
- Howard Hughes Medical Institute, Department of Biology, Stanford UniversityStanfordUnited States
| | - Sydney S Sirota
- Department of Biochemistry and Cell Biology, Stony Brook UniversityStony BrookUnited States
| | - Angelina A Mullarkey
- Department of Biochemistry and Cell Biology, Stony Brook UniversityStony BrookUnited States
| | - Neha Somineni
- Department of Biochemistry and Cell Biology, Stony Brook UniversityStony BrookUnited States
| | - Justin Hippler
- Department of Biochemistry and Cell Biology, Stony Brook UniversityStony BrookUnited States
- Science and Technology Research Program, Smithtown High School EastSt. JamesUnited States
| | - Wan Zhang
- Department of Biochemistry and Cell Biology, Stony Brook UniversityStony BrookUnited States
| | - Kang Shen
- Howard Hughes Medical Institute, Department of Biology, Stanford UniversityStanfordUnited States
| | | | - Ariel M Pani
- Departments of Biology and Cell Biology, University of VirginiaCharlottesvilleUnited States
| | - David Q Matus
- Department of Biochemistry and Cell Biology, Stony Brook UniversityStony BrookUnited States
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5
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Xu J, Sun Y, Fu W, Fu S. MYCT1 in cancer development: Gene structure, regulation, and biological implications for diagnosis and treatment. Biomed Pharmacother 2023; 165:115208. [PMID: 37499454 DOI: 10.1016/j.biopha.2023.115208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 07/10/2023] [Accepted: 07/19/2023] [Indexed: 07/29/2023] Open
Abstract
Myc target 1 (MYCT1), located at 6q25.2, is a crucial player in cancer development. While widely distributed in cells, its subcellular localization varies across different cancer types. As a novel c-Myc target gene, MYCT1 is subject to regulation by multiple transcription factors. Studies have revealed aberrant expression of MYCT1 in various cancers, impacting pivotal biological processes such as proliferation, apoptosis, migration, genomic instability, and differentiation in cancer cells. Additionally, MYCT1 plays a critical role in modulating tumor angiogenesis and remodeling tumor immune responses within the tumor microenvironment. Despite certain debated functions, MYCT1 undeniably holds significance in cancer development. In this review, we comprehensively examine the relationship between MYCT1 and cancer, encompassing gene structure, regulation of gene expression, gene mutation, and biological function, with the aim of providing valuable insights for cancer diagnosis and treatment.
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Affiliation(s)
- Jianan Xu
- Department of Medical genetics, China Medical University, Shenyang 110022, PR China
| | - Yuanyuan Sun
- Department of Medical genetics, China Medical University, Shenyang 110022, PR China
| | - Weineng Fu
- Department of Medical genetics, China Medical University, Shenyang 110022, PR China
| | - Shuang Fu
- Department of Hematology Laboratory, Shengjing Hospital of China Medical University, Shenyang 110022, PR China; Department of Medical genetics, China Medical University, Shenyang 110022, PR China.
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6
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Ghaddar A, Armingol E, Huynh C, Gevirtzman L, Lewis NE, Waterston R, O’Rourke EJ. Whole-body gene expression atlas of an adult metazoan. SCIENCE ADVANCES 2023; 9:eadg0506. [PMID: 37352352 PMCID: PMC10289653 DOI: 10.1126/sciadv.adg0506] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Accepted: 05/17/2023] [Indexed: 06/25/2023]
Abstract
Gene activity defines cell identity, drives intercellular communication, and underlies the functioning of multicellular organisms. We present the single-cell resolution atlas of gene activity of a fertile adult metazoan: Caenorhabditis elegans. This compendium comprises 180 distinct cell types and 19,657 expressed genes. We predict 7541 transcription factor expression profile associations likely responsible for defining cellular identity. We predict thousands of intercellular interactions across the C. elegans body and the ligand-receptor pairs that mediate them, some of which we experimentally validate. We identify 172 genes that show consistent expression across cell types, are involved in basic and essential functions, and are conserved across phyla; therefore, we present them as experimentally validated housekeeping genes. We developed the WormSeq application to explore these data. In addition to the integrated gene-to-systems biology, we present genome-scale single-cell resolution testable hypotheses that we anticipate will advance our understanding of the molecular mechanisms, underlying the functioning of a multicellular organism and the perturbations that lead to its malfunction.
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Affiliation(s)
- Abbas Ghaddar
- Department of Biology, College of Arts and Sciences, University of Virginia, Charlottesville, VA 22903, USA
| | - Erick Armingol
- Bioinformatics and Systems Biology Graduate Program, University of California, San Diego, La Jolla, CA 92093, USA
- Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA
| | - Chau Huynh
- Department of Genome Sciences, University of Washington, Seattle, WA 98195, USA
| | - Louis Gevirtzman
- Department of Genome Sciences, University of Washington, Seattle, WA 98195, USA
| | - Nathan E. Lewis
- Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA
- Department of Bioengineering, University of California, San Diego, La Jolla, CA 92093, USA
| | - Robert Waterston
- Department of Genome Sciences, University of Washington, Seattle, WA 98195, USA
| | - Eyleen J. O’Rourke
- Department of Biology, College of Arts and Sciences, University of Virginia, Charlottesville, VA 22903, USA
- Department of Cell Biology, University of Virginia School of Medicine, Charlottesville, VA 22903, USA
- Robert M. Berne Cardiovascular Research Center, School of Medicine, University of Virginia, Charlottesville, VA 22903, USA
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7
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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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8
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Rashid A, Tevlin M, Lu Y, Shaham S. A developmental pathway for epithelial-to-motoneuron transformation in C. elegans. Cell Rep 2022; 40:111414. [PMID: 36170838 PMCID: PMC9579992 DOI: 10.1016/j.celrep.2022.111414] [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: 12/21/2021] [Revised: 07/18/2022] [Accepted: 09/01/2022] [Indexed: 11/24/2022] Open
Abstract
Motoneurons and motoneuron-like pancreatic β cells arise from radial glia and ductal cells, respectively, both tube-lining progenitors that share molecular regulators. To uncover programs underlying motoneuron formation, we studied a similar, cell-division-independent transformation of the C. elegans tube-lining Y cell into the PDA motoneuron. We find that lin-12/Notch acts through ngn-1/Ngn and its regulator hlh-16/Olig to control transformation timing. lin-12 loss blocks transformation, while lin-12(gf) promotes precocious PDA formation. Early basal expression of ngn-1/Ngn and hlh-16/Olig depends on sem-4/Sall and egl-5/Hox. Later, coincident with Y cell morphological changes, ngn-1/Ngn expression is upregulated in a sem-4/Sall and egl-5/Hox-dependent but hlh-16/Olig-independent manner. Subsequently, Y cell retrograde extension forms an anchored process priming PDA axon extension. Extension requires ngn-1-dependent expression of the cytoskeleton organizers UNC-119, UNC-44/ANK, and UNC-33/CRMP, which also activate PDA terminal-gene expression. Our findings uncover cell-division-independent regulatory events leading to motoneuron generation, suggesting a conserved pathway for epithelial-to-motoneuron/motoneuron-like cell differentiation. Rashid et al. report on a conserved epithelial-to-motoneuron transformation pathway in C. elegans requiring ngn-1/Ngn and hlh-16/Olig. lin-12/Notch regulates transformation timing through these genes, while ngn-1/Ngn and hlh-16/Olig expression levels are regulated by sem-4/Sall and egl-5/Hox. Unexpectedly, the cytoskeleton organizers UNC-119, UNC-44, and UNC-33, which are ngn-1/Ngn targets, promote motoneuron terminal identity.
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Affiliation(s)
- Alina Rashid
- Laboratory of Developmental Genetics, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | - Maya Tevlin
- Laboratory of Developmental Genetics, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | - Yun Lu
- Laboratory of Developmental Genetics, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | - Shai Shaham
- Laboratory of Developmental Genetics, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA.
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9
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Bacterial diet modulates tamoxifen-induced death via host fatty acid metabolism. Nat Commun 2022; 13:5595. [PMID: 36151093 PMCID: PMC9508336 DOI: 10.1038/s41467-022-33299-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Accepted: 09/06/2022] [Indexed: 11/18/2022] Open
Abstract
Tamoxifen is a selective estrogen receptor (ER) modulator that is used to treat ER-positive breast cancer, but that at high doses kills both ER-positive and ER-negative breast cancer cells. We recapitulate this off-target effect in Caenorhabditis elegans, which does not have an ER ortholog. We find that different bacteria dramatically modulate tamoxifen toxicity in C. elegans, with a three-order of magnitude difference between animals fed Escherichia coli, Comamonas aquatica, and Bacillus subtilis. Remarkably, host fatty acid (FA) biosynthesis mitigates tamoxifen toxicity, and different bacteria provide the animal with different FAs, resulting in distinct FA profiles. Surprisingly these bacteria modulate tamoxifen toxicity by different death mechanisms, some of which are modulated by FA supplementation and others by antioxidants. Together, this work reveals a complex interplay between microbiota, FA metabolism and tamoxifen toxicity that may provide a blueprint for similar studies in more complex mammals. Here, Diot et al. use the nematode Caenorhabditis elegans as a model to identify off-target toxicity mechanisms for tamoxifen, and find that these include fatty acid metabolism and cell death, which can be modulated by different bacterial species.
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10
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Guttery DS, Zeeshan M, Ferguson DJP, Holder AA, Tewari R. Division and Transmission: Malaria Parasite Development in the Mosquito. Annu Rev Microbiol 2022; 76:113-134. [PMID: 35609946 DOI: 10.1146/annurev-micro-041320-010046] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The malaria parasite life cycle alternates between two hosts: a vertebrate and the female Anopheles mosquito vector. Cell division, proliferation, and invasion are essential for parasite development, transmission, and survival. Most research has focused on Plasmodium development in the vertebrate, which causes disease; however, knowledge of malaria parasite development in the mosquito (the sexual and transmission stages) is now rapidly accumulating, gathered largely through investigation of the rodent malaria model, with Plasmodium berghei. In this review, we discuss the seminal genome-wide screens that have uncovered key regulators of cell proliferation, invasion, and transmission during Plasmodium sexual development. Our focus is on the roles of transcription factors, reversible protein phosphorylation, and molecular motors. We also emphasize the still-unanswered important questions around key pathways in cell division during the vector transmission stages and how they may be targeted in future studies.
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Affiliation(s)
- David S Guttery
- School of Life Sciences, University of Nottingham, Nottingham, United Kingdom; ,
- Leicester Cancer Research Centre, University of Leicester, Leicester, United Kingdom;
| | - Mohammad Zeeshan
- School of Life Sciences, University of Nottingham, Nottingham, United Kingdom; ,
| | - David J P Ferguson
- Nuffield Department of Clinical Laboratory Sciences and John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom;
- Department of Biological and Medical Sciences, Faculty of Health and Life Sciences, Oxford Brookes University, Oxford, United Kingdom
| | - Anthony A Holder
- Malaria Parasitology Laboratory, Francis Crick Institute, London, United Kingdom;
| | - Rita Tewari
- School of Life Sciences, University of Nottingham, Nottingham, United Kingdom; ,
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11
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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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12
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Godini R, Handley A, Pocock R. Transcription Factors That Control Behavior-Lessons From C. elegans. Front Neurosci 2021; 15:745376. [PMID: 34646119 PMCID: PMC8503520 DOI: 10.3389/fnins.2021.745376] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Accepted: 09/02/2021] [Indexed: 11/15/2022] Open
Abstract
Behavior encompasses the physical and chemical response to external and internal stimuli. Neurons, each with their own specific molecular identities, act in concert to perceive and relay these stimuli to drive behavior. Generating behavioral responses requires neurons that have the correct morphological, synaptic, and molecular identities. Transcription factors drive the specific gene expression patterns that define these identities, controlling almost every phenomenon in a cell from development to homeostasis. Therefore, transcription factors play an important role in generating and regulating behavior. Here, we describe the transcription factors, the pathways they regulate, and the neurons that drive chemosensation, mechanosensation, thermosensation, osmolarity sensing, complex, and sex-specific behaviors in the animal model Caenorhabditis elegans. We also discuss the current limitations in our knowledge, particularly our minimal understanding of how transcription factors contribute to the adaptive behavioral responses that are necessary for organismal survival.
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A 4D single-cell protein atlas of transcription factors delineates spatiotemporal patterning during embryogenesis. Nat Methods 2021; 18:893-902. [PMID: 34312566 DOI: 10.1038/s41592-021-01216-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Accepted: 06/17/2021] [Indexed: 12/27/2022]
Abstract
Complex biological processes such as embryogenesis require precise coordination of cell differentiation programs across both space and time. Using protein-fusion fluorescent reporters and four-dimensional live imaging, we present a protein expression atlas of transcription factors (TFs) mapped onto developmental cell lineages during Caenorhabditis elegans embryogenesis, at single-cell resolution. This atlas reveals a spatiotemporal combinatorial code of TF expression, and a cascade of lineage-specific, tissue-specific and time-specific TFs that specify developmental states. The atlas uncovers regulators of embryogenesis, including an unexpected role of a skin specifier in neurogenesis and the critical function of an uncharacterized TF in convergent muscle differentiation. At the systems level, the atlas provides an opportunity to model cell state-fate relationships, revealing a lineage-dependent state diversity within functionally related cells and a winding trajectory of developmental state progression. Collectively, this single-cell protein atlas represents a valuable resource for elucidating metazoan embryogenesis at the molecular and systems levels.
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14
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Ma F, Lau CY, Zheng C. Large genetic diversity and strong positive selection in F-box and GPCR genes among the wild isolates of Caenorhabditis elegans. Genome Biol Evol 2021; 13:6163285. [PMID: 33693740 PMCID: PMC8120010 DOI: 10.1093/gbe/evab048] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 02/17/2021] [Accepted: 03/03/2021] [Indexed: 01/05/2023] Open
Abstract
The F-box and chemosensory GPCR (csGPCR) gene families are greatly expanded in nematodes, including the model organism Caenorhabditis elegans, compared with insects and vertebrates. However, the intraspecific evolution of these two gene families in nematodes remain unexamined. In this study, we analyzed the genomic sequences of 330 recently sequenced wild isolates of C. elegans using a range of population genetics approaches. We found that F-box and csGPCR genes, especially the Srw family csGPCRs, showed much more diversity than other gene families. Population structure analysis and phylogenetic analysis divided the wild strains into eight non-Hawaiian and three Hawaiian subpopulations. Some Hawaiian strains appeared to be more ancestral than all other strains. F-box and csGPCR genes maintained a great amount of the ancestral variants in the Hawaiian subpopulation and their divergence among the non-Hawaiian subpopulations contributed significantly to population structure. F-box genes are mostly located at the chromosomal arms and high recombination rate correlates with their large polymorphism. Moreover, using both neutrality tests and extended haplotype homozygosity analysis, we identified signatures of strong positive selection in the F-box and csGPCR genes among the wild isolates, especially in the non-Hawaiian population. Accumulation of high-frequency-derived alleles in these genes was found in non-Hawaiian population, leading to divergence from the ancestral genotype. In summary, we found that F-box and csGPCR genes harbor a large pool of natural variants, which may be subjected to positive selection. These variants are mostly mapped to the substrate-recognition domains of F-box proteins and the extracellular and intracellular regions of csGPCRs, possibly resulting in advantages during adaptation by affecting protein degradation and the sensing of environmental cues, respectively.
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Affiliation(s)
- Fuqiang Ma
- School of Biological Sciences, The University of Hong Kong, Hong Kong SAR, China
| | - Chun Yin Lau
- School of Biological Sciences, The University of Hong Kong, Hong Kong SAR, China
| | - Chaogu Zheng
- School of Biological Sciences, The University of Hong Kong, Hong Kong SAR, China
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15
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Internetwork connectivity of molecular networks across species of life. Sci Rep 2021; 11:1168. [PMID: 33441907 PMCID: PMC7806680 DOI: 10.1038/s41598-020-80745-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Accepted: 12/23/2020] [Indexed: 01/29/2023] Open
Abstract
Molecular interactions are studied as independent networks in systems biology. However, molecular networks do not exist independently of each other. In a network of networks approach (called multiplex), we study the joint organization of transcriptional regulatory network (TRN) and protein-protein interaction (PPI) network. We find that TRN and PPI are non-randomly coupled across five different eukaryotic species. Gene degrees in TRN (number of downstream genes) are positively correlated with protein degrees in PPI (number of interacting protein partners). Gene-gene and protein-protein interactions in TRN and PPI, respectively, also non-randomly overlap. These design principles are conserved across the five eukaryotic species. Robustness of the TRN-PPI multiplex is dependent on this coupling. Functionally important genes and proteins, such as essential, disease-related and those interacting with pathogen proteins, are preferentially situated in important parts of the human multiplex with highly overlapping interactions. We unveil the multiplex architecture of TRN and PPI. Multiplex architecture may thus define a general framework for studying molecular networks. This approach may uncover the building blocks of the hierarchical organization of molecular interactions.
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Combining Auxin-Induced Degradation and RNAi Screening Identifies Novel Genes Involved in Lipid Bilayer Stress Sensing in Caenorhabditis elegans. G3-GENES GENOMES GENETICS 2020; 10:3921-3928. [PMID: 32958476 PMCID: PMC7642917 DOI: 10.1534/g3.120.401635] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Alteration of the lipid composition of biological membranes interferes with their function and can cause tissue damage by triggering apoptosis. Upon lipid bilayer stress, the endoplasmic reticulum mounts a stress response similar to the unfolded protein response. However, only a few genes are known to regulate lipid bilayer stress. We performed a suppressor screen that combined the auxin-inducible degradation (AID) system with conventional RNAi in C. elegans to identify members of the lipid bilayer stress response. AID-mediated degradation of the mediator MDT-15, a protein required for the upregulation of fatty acid desaturases, induced the activation of lipid bilayer stress-sensitive reporters. We screened through most C. elegans kinases and transcription factors by feeding RNAi. We discovered nine genes that suppressed the lipid bilayer stress response in C. elegans. These suppressor genes included drl-1/MAP3K3, gsk-3/GSK3, let-607/CREB3, ire-1/IRE1, and skn-1/NRF1,2,3. Our candidate suppressor genes suggest a network of transcription factors and the integration of multiple tissues for a centralized lipotoxicity response in the intestine. Thus, we demonstrated proof-of-concept for combining AID and RNAi as a new screening strategy and identified eight conserved genes that had not previously been implicated in the lipid bilayer stress response.
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17
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Barabási DL, Barabási AL. A Genetic Model of the Connectome. Neuron 2020; 105:435-445.e5. [PMID: 31806491 PMCID: PMC7007360 DOI: 10.1016/j.neuron.2019.10.031] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 10/07/2019] [Accepted: 10/24/2019] [Indexed: 11/18/2022]
Abstract
The connectomes of organisms of the same species show remarkable architectural and often local wiring similarity, raising the question: where and how is neuronal connectivity encoded? Here, we start from the hypothesis that the genetic identity of neurons guides synapse and gap-junction formation and show that such genetically driven wiring predicts the existence of specific biclique motifs in the connectome. We identify a family of large, statistically significant biclique subgraphs in the connectomes of three species and show that within many of the observed bicliques the neurons share statistically significant expression patterns and morphological characteristics, supporting our expectation of common genetic factors that drive the synapse formation within these subgraphs. The proposed connectome model offers a self-consistent framework to link the genetics of an organism to the reproducible architecture of its connectome, offering experimentally falsifiable predictions on the genetic factors that drive the formation of individual neuronal circuits.
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Affiliation(s)
| | - Albert-László Barabási
- Network Science Institute, Northeastern University, Boston, MA 02115, USA; Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA; Department of Data and Network Science, Central European University, Budapest 1051, Hungary.
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18
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Kim Y, Jeong J, Chatterjee N, Yim UH, Kwon JH, Park MS, Choi J. Activation of the nucleotide excision repair pathway by crude oil exposure: A translational study from model organisms to the Hebei Spirit Oil Spill Cohort. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2019; 254:112997. [PMID: 31454576 DOI: 10.1016/j.envpol.2019.112997] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Revised: 07/26/2019] [Accepted: 07/28/2019] [Indexed: 06/10/2023]
Abstract
In order to gain insight into the human health implications of the Hebei Spirit Oil Spill (HSOS), the mechanism of toxicity of the Iranian heavy crude (IHC), the main oil component in the HSOS was investigated in Caenorhabditis elegans and zebrafish. The identified mechanism was translated to humans using blood samples from Taean residents, who experienced HSOS with different levels of exposure to the spill. C. elegans TF RNAi screening with IHC oil revealed the nucleotide excision repair (NER) pathway as being significantly involved by oil exposure. To identify the main toxicity contributors within the chemical mixture of the crude oil, further studies were conducted on C. elegans by exposure to C3-naphthalene, an alkylated polycyclic aromatic hydrocarbon (PAH), which constitutes one of the major components of IHC oil. Increased expression of NER pathway genes was observed following exposure to the IHC oil, C3-naphthalene enriched fraction and C3-naphthalene. As the NER pathway is conserved in fish and humans, the same experiment was conducted in zebrafish, and the data were similar to what was seen in C. elegans. Increased expression of NER pathway genes was observed in human samples from the high exposure group, which suggests the involvement of the NER pathway in IHC oil exposure. Overall, the study suggests that IHC oil may cause bulk damage to DNA and activation of the NER system and Alkylated PAHs are the major contributor to DNA damage. Our study provides an innovative approach for studying translational toxicity testing from model organisms to human health.
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Affiliation(s)
- Youngho Kim
- School of Environmental Engineering, University of Seoul, 163 Siripdaero, Dongdaemun-gu, Seoul 02504, Republic of Korea
| | - Jaeseong Jeong
- School of Environmental Engineering, University of Seoul, 163 Siripdaero, Dongdaemun-gu, Seoul 02504, Republic of Korea
| | - Nivedita Chatterjee
- School of Environmental Engineering, University of Seoul, 163 Siripdaero, Dongdaemun-gu, Seoul 02504, Republic of Korea
| | - Un Hyuk Yim
- Oil & POPs Research Group, Korea Institute of Ocean Science & Technology, Geoje, 53201, Republic of Korea; Ocean Science, Korea University of Science and Technology, Daejeon 34113, Republic of Korea
| | - Jung-Hwan Kwon
- Division of Environmental Science and Ecological Engineering, Korea University, Seongbuk-gu, Seoul 02841, Republic of Korea
| | - Myung-Sook Park
- Taean Environmental Health Center, 1952-16 Seohae-ro, Taean-eup, Taean-gun Chungcheongnam-do 32148, Republic of Korea
| | - Jinhee Choi
- School of Environmental Engineering, University of Seoul, 163 Siripdaero, Dongdaemun-gu, Seoul 02504, Republic of Korea.
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Early life exposure of a biocide, CMIT/MIT causes metabolic toxicity via the O-GlcNAc transferase pathway in the nematode C. elegans. Toxicol Appl Pharmacol 2019; 376:1-8. [PMID: 31100289 DOI: 10.1016/j.taap.2019.05.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 04/28/2019] [Accepted: 05/13/2019] [Indexed: 10/26/2022]
Abstract
Unusual cases of fatal lung injury, later determined to be a result of exposure to chemicals used as humidifier disinfectants, were reported among Korean children from 2006 to 2011. This resulted in considerable study of the pulmonary toxicity of humidifier disinfectant chemicals to establish the causal relationship between exposure and lung disease. However, the systemic toxicity of the former and health effects other than lung disease are not fully understood. Here, we investigated the effect of 5-chloro-2-methyl-4-isothiazoline-3-one and 2-methyl-4-isothiazolin-3-one (CMIT/MIT), among the humidifier disinfectants used in the accidents, on the development of metabolic toxicity in the model organism, Caenorhabditis elegans using an exposure scenario comparison. We screened the potential of CMIT/MIT to induce metabolic toxicity using C. elegans oga-1(ok1207) and ogt-1(ok1474) mutants. We also performed a pathway analysis based on C. elegans transcription factor RNAi library screening to identify the underlying toxicity mechanisms. Finally, to understand the critical window of exposure for metabolic toxicity, responses to exposure during different periods in the life cycles of the worms were compared. We determined that CMIT/MIT could induce metabolic toxicity through O-linked N-acetylglucosamine transferase and early life seems to be the critical window for exposure for metabolic toxicity for this substance. The O-linked N-acetylglucosamine transferase pathway is conserved from worms to humans; our results thus insinuate that early-life exposure to CMIT/MIT could cause metabolic health problems during adult life in humans. We therefore suggest that a systemic toxicity approach should be considered to comprehensively understand the adverse health effects of humidifier disinfectant misuse.
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Godini R, Pocock R, Fallahi H. Caenorhabditis elegans hub genes that respond to amyloid beta are homologs of genes involved in human Alzheimer's disease. PLoS One 2019; 14:e0219486. [PMID: 31291334 PMCID: PMC6619800 DOI: 10.1371/journal.pone.0219486] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Accepted: 06/25/2019] [Indexed: 12/31/2022] Open
Abstract
The prominent characteristic of Alzheimer’s disease (AD) is the accumulation of amyloid beta (Abeta) proteins in the form of plaques that cause molecular and cellular alterations in the brain. Due to the paucity of brain samples of early-stage Abeta aggregation, animal models have been developed to study early events in AD. Caenorhabditis elegans is a genetically tractable animal model for AD. Here, we used transcriptomic data, network-based protein-protein interactions and weighted gene co-expression network analysis (WGCNA), to detect modules and their gene ontology in response to Abeta aggregation in C. elegans. Additionally, hub genes and their orthologues in human and mouse were identified to study their relation to AD. We also found several transcription factors (TFs) responding to Abeta accumulation. Our results show that Abeta expression in C. elegans relates to general processes such as molting cycle, locomotion, and larval development plus AD-associated processes, including protein phosphorylation, and G-protein coupled receptor-regulated pathways. We reveal that many hub genes and TFs including ttbk-2, daf-16, and unc-49 have human and mouse orthologues that are directly or potentially associated with AD and neural development. In conclusion, using systems biology we identified important genes and biological processes in C. elegans that respond to Abeta aggregation, which could be used as potential diagnostic or therapeutic targets. In addition, because of evolutionary relationship to AD in human, we suggest that C. elegans is a useful model for studying early molecular events in AD.
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Affiliation(s)
- Rasoul Godini
- Department of Biology, School of Sciences, Razi University, Kermanshah, Iran
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia
| | - Roger Pocock
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia
| | - Hossein Fallahi
- Department of Biology, School of Sciences, Razi University, Kermanshah, Iran
- * E-mail:
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21
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Mathies LD, Ray S, Lopez-Alvillar K, Arbeitman MN, Davies AG, Bettinger JC. mRNA profiling reveals significant transcriptional differences between a multipotent progenitor and its differentiated sister. BMC Genomics 2019; 20:427. [PMID: 31138122 PMCID: PMC6540470 DOI: 10.1186/s12864-019-5821-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Accepted: 05/21/2019] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND The two Caenorhabditis elegans somatic gonadal precursors (SGPs) are multipotent progenitors that generate all somatic tissues of the adult reproductive system. The sister cells of the SGPs are two head mesodermal cells (hmcs); one hmc dies by programmed cell death and the other terminally differentiates. Thus, a single cell division gives rise to one multipotent progenitor and one differentiated cell with identical lineage histories. We compared the transcriptomes of SGPs and hmcs in order to learn the determinants of multipotency and differentiation in this lineage. RESULTS We generated a strain that expressed fluorescent markers specifically in SGPs (ehn-3A::tdTomato) and hmcs (bgal-1::GFP). We dissociated cells from animals after the SGP/hmc cell division, but before the SGPs had further divided, and subjected the dissociated cells to fluorescence-activated cell sorting to collect isolated SGPs and hmcs. We analyzed the transcriptomes of these cells and found that 5912 transcripts were significantly differentially expressed, with at least two-fold change in expression, between the two cell types. The hmc-biased genes were enriched with those that are characteristic of neurons. The SGP-biased genes were enriched with those indicative of cell proliferation and development. We assessed the validity of our differentially expressed genes by examining existing reporters for five of the 10 genes with the most significantly biased expression in SGPs and found that two showed expression in SGPs. For one reporter that did not show expression in SGPs, we generated a GFP knock-in using CRISPR/Cas9. This reporter, in the native genomic context, was expressed in SGPs. CONCLUSIONS We found that the transcriptional profiles of SGPs and hmcs are strikingly different. The hmc-biased genes are enriched with those that encode synaptic transmission machinery, which strongly suggests that it has neuron-like signaling properties. In contrast, the SGP-biased genes are enriched with genes that encode factors involved in transcription and translation, as would be expected from a cell preparing to undergo proliferative divisions. Mediators of multipotency are likely to be among the genes differentially expressed in SGPs.
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Affiliation(s)
- Laura D. Mathies
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, PO Box 980613, Richmond, VA 23298 USA
| | - Surjyendu Ray
- Department of Biomedical Sciences, College of Medicine, Florida State University, Tallahassee, FL 32306 USA
| | - Kayla Lopez-Alvillar
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, PO Box 980613, Richmond, VA 23298 USA
| | - Michelle N. Arbeitman
- Department of Biomedical Sciences, College of Medicine, Florida State University, Tallahassee, FL 32306 USA
| | - Andrew G. Davies
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, PO Box 980613, Richmond, VA 23298 USA
| | - Jill C. Bettinger
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, PO Box 980613, Richmond, VA 23298 USA
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Abstract
Comprehensive mapping of protein-DNA interactions is essential to uncover the mechanisms involved in gene regulation. However, the data generated has been sparse given the number of regulatory elements and transcription factors (TFs) encoded in the genomes of metazoan organisms. Yeast one-hybrid (Y1H) assays provide a powerful "DNA-centered" method, complementary to "TF-centered" methods such as chromatin immunoprecipitation, to identify the TFs that can bind a DNA sequence of interest. Here, we present different technical variations that should be considered when using a Y1H system, including the type of DNA sequence to test, source of TF clones, as well as types of vectors and screening format. Finally, we discuss limitations of the assay and future challenges.
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23
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Kaletsky R, Yao V, Williams A, Runnels AM, Tadych A, Zhou S, Troyanskaya OG, Murphy CT. Transcriptome analysis of adult Caenorhabditis elegans cells reveals tissue-specific gene and isoform expression. PLoS Genet 2018; 14:e1007559. [PMID: 30096138 PMCID: PMC6105014 DOI: 10.1371/journal.pgen.1007559] [Citation(s) in RCA: 125] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Revised: 08/22/2018] [Accepted: 07/13/2018] [Indexed: 12/19/2022] Open
Abstract
The biology and behavior of adults differ substantially from those of developing animals, and cell-specific information is critical for deciphering the biology of multicellular animals. Thus, adult tissue-specific transcriptomic data are critical for understanding molecular mechanisms that control their phenotypes. We used adult cell-specific isolation to identify the transcriptomes of C. elegans' four major tissues (or "tissue-ome"), identifying ubiquitously expressed and tissue-specific "enriched" genes. These data newly reveal the hypodermis' metabolic character, suggest potential worm-human tissue orthologies, and identify tissue-specific changes in the Insulin/IGF-1 signaling pathway. Tissue-specific alternative splicing analysis identified a large set of collagen isoforms. Finally, we developed a machine learning-based prediction tool for 76 sub-tissue cell types, which we used to predict cellular expression differences in IIS/FOXO signaling, stage-specific TGF-β activity, and basal vs. memory-induced CREB transcription. Together, these data provide a rich resource for understanding the biology governing multicellular adult animals.
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Affiliation(s)
- Rachel Kaletsky
- Department of Molecular Biology, Princeton University, Princeton, New Jersey, United States of America
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, United States of America
| | - Victoria Yao
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, United States of America
- Department of Computer Science, Princeton University, Princeton, New Jersey, United States of America
| | - April Williams
- Department of Molecular Biology, Princeton University, Princeton, New Jersey, United States of America
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, United States of America
| | - Alexi M. Runnels
- Department of Molecular Biology, Princeton University, Princeton, New Jersey, United States of America
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, United States of America
| | - Alicja Tadych
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, United States of America
| | - Shiyi Zhou
- Department of Molecular Biology, Princeton University, Princeton, New Jersey, United States of America
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, United States of America
| | - Olga G. Troyanskaya
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, United States of America
- Department of Computer Science, Princeton University, Princeton, New Jersey, United States of America
- Flatiron Institute, Simons Foundation, New York, New York, United States of America
| | - Coleen T. Murphy
- Department of Molecular Biology, Princeton University, Princeton, New Jersey, United States of America
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, United States of America
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Reece-Hoyes JS, Walhout AJM. Gateway-Compatible Yeast One-Hybrid and Two-Hybrid Assays. Cold Spring Harb Protoc 2018; 2018:2018/7/pdb.top094953. [PMID: 29967278 DOI: 10.1101/pdb.top094953] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
In the first section of this introduction, we provide background information for yeast two-hybrid (Y2H) assays that provide a genetic method for the identification and analysis of binary protein-protein interactions and that are complementary to biochemical methods such as immunoprecipitation. In the second section, we discuss yeast one-hybrid (Y1H) assays that provide a "gene-centered" (DNA-to-protein) genetic method to identify and study protein-DNA interactions between cis-regulatory elements and transcription factors (TFs). This method is complementary to "TF-centered" (protein-to-DNA) biochemical methods such as chromatin immunoprecipitation.
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25
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Polanowska J, Chen JX, Soulé J, Omi S, Belougne J, Taffoni C, Pujol N, Selbach M, Zugasti O, Ewbank JJ. Evolutionary plasticity in the innate immune function of Akirin. PLoS Genet 2018; 14:e1007494. [PMID: 30036395 PMCID: PMC6072134 DOI: 10.1371/journal.pgen.1007494] [Citation(s) in RCA: 27] [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: 01/09/2018] [Revised: 08/02/2018] [Accepted: 06/16/2018] [Indexed: 12/22/2022] Open
Abstract
Eukaryotic gene expression requires the coordinated action of transcription factors, chromatin remodelling complexes and RNA polymerase. The conserved nuclear protein Akirin plays a central role in immune gene expression in insects and mammals, linking the SWI/SNF chromatin-remodelling complex with the transcription factor NFκB. Although nematodes lack NFκB, Akirin is also indispensable for the expression of defence genes in the epidermis of Caenorhabditis elegans following natural fungal infection. Through a combination of reverse genetics and biochemistry, we discovered that in C. elegans Akirin has conserved its role of bridging chromatin-remodellers and transcription factors, but that the identity of its functional partners is different since it forms a physical complex with NuRD proteins and the POU-class transcription factor CEH-18. In addition to providing a substantial step forward in our understanding of innate immune gene regulation in C. elegans, our results give insight into the molecular evolution of lineage-specific signalling pathways.
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Affiliation(s)
| | - Jia-Xuan Chen
- Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Julien Soulé
- Aix Marseille Univ, CNRS, INSERM, CIML, Marseille, France
| | - Shizue Omi
- Aix Marseille Univ, CNRS, INSERM, CIML, Marseille, France
| | | | - Clara Taffoni
- Aix Marseille Univ, CNRS, INSERM, CIML, Marseille, France
| | - Nathalie Pujol
- Aix Marseille Univ, CNRS, INSERM, CIML, Marseille, France
| | - Matthias Selbach
- Max Delbrück Center for Molecular Medicine, Berlin, Germany
- Charité-Universitätsmedizin Berlin, Berlin, Germany
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Kudron MM, Victorsen A, Gevirtzman L, Hillier LW, Fisher WW, Vafeados D, Kirkey M, Hammonds AS, Gersch J, Ammouri H, Wall ML, Moran J, Steffen D, Szynkarek M, Seabrook-Sturgis S, Jameel N, Kadaba M, Patton J, Terrell R, Corson M, Durham TJ, Park S, Samanta S, Han M, Xu J, Yan KK, Celniker SE, White KP, Ma L, Gerstein M, Reinke V, Waterston RH. The ModERN Resource: Genome-Wide Binding Profiles for Hundreds of Drosophila and Caenorhabditis elegans Transcription Factors. Genetics 2018; 208:937-949. [PMID: 29284660 PMCID: PMC5844342 DOI: 10.1534/genetics.117.300657] [Citation(s) in RCA: 113] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Accepted: 12/08/2017] [Indexed: 12/22/2022] Open
Abstract
To develop a catalog of regulatory sites in two major model organisms, Drosophila melanogaster and Caenorhabditis elegans, the modERN (model organism Encyclopedia of Regulatory Networks) consortium has systematically assayed the binding sites of transcription factors (TFs). Combined with data produced by our predecessor, modENCODE (Model Organism ENCyclopedia Of DNA Elements), we now have data for 262 TFs identifying 1.23 M sites in the fly genome and 217 TFs identifying 0.67 M sites in the worm genome. Because sites from different TFs are often overlapping and tightly clustered, they fall into 91,011 and 59,150 regions in the fly and worm, respectively, and these binding sites span as little as 8.7 and 5.8 Mb in the two organisms. Clusters with large numbers of sites (so-called high occupancy target, or HOT regions) predominantly associate with broadly expressed genes, whereas clusters containing sites from just a few factors are associated with genes expressed in tissue-specific patterns. All of the strains expressing GFP-tagged TFs are available at the stock centers, and the chromatin immunoprecipitation sequencing data are available through the ENCODE Data Coordinating Center and also through a simple interface (http://epic.gs.washington.edu/modERN/) that facilitates rapid accessibility of processed data sets. These data will facilitate a vast number of scientific inquiries into the function of individual TFs in key developmental, metabolic, and defense and homeostatic regulatory pathways, as well as provide a broader perspective on how individual TFs work together in local networks and globally across the life spans of these two key model organisms.
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Affiliation(s)
- Michelle M Kudron
- Department of Genetics, Yale University, New Haven, Connecticut 06520
| | - Alec Victorsen
- Institute for Genomics and Systems Biology, Department of Human Genetics, University of Chicago, Illinois 60637
| | - Louis Gevirtzman
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, Washington 98195
| | - LaDeana W Hillier
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, Washington 98195
| | - William W Fisher
- Division of Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, California 94720
| | - Dionne Vafeados
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, Washington 98195
| | - Matt Kirkey
- Institute for Genomics and Systems Biology, Department of Human Genetics, University of Chicago, Illinois 60637
| | - Ann S Hammonds
- Division of Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, California 94720
| | - Jeffery Gersch
- Institute for Genomics and Systems Biology, Department of Human Genetics, University of Chicago, Illinois 60637
| | - Haneen Ammouri
- Institute for Genomics and Systems Biology, Department of Human Genetics, University of Chicago, Illinois 60637
| | - Martha L Wall
- Institute for Genomics and Systems Biology, Department of Human Genetics, University of Chicago, Illinois 60637
| | - Jennifer Moran
- Institute for Genomics and Systems Biology, Department of Human Genetics, University of Chicago, Illinois 60637
| | - David Steffen
- Institute for Genomics and Systems Biology, Department of Human Genetics, University of Chicago, Illinois 60637
| | - Matt Szynkarek
- Institute for Genomics and Systems Biology, Department of Human Genetics, University of Chicago, Illinois 60637
| | - Samantha Seabrook-Sturgis
- Institute for Genomics and Systems Biology, Department of Human Genetics, University of Chicago, Illinois 60637
| | - Nader Jameel
- Institute for Genomics and Systems Biology, Department of Human Genetics, University of Chicago, Illinois 60637
| | - Madhura Kadaba
- Institute for Genomics and Systems Biology, Department of Human Genetics, University of Chicago, Illinois 60637
| | - Jaeda Patton
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, Washington 98195
| | - Robert Terrell
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, Washington 98195
| | - Mitch Corson
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, Washington 98195
| | - Timothy J Durham
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, Washington 98195
| | - Soo Park
- Division of Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, California 94720
| | - Swapna Samanta
- Department of Genetics, Yale University, New Haven, Connecticut 06520
| | - Mei Han
- Department of Genetics, Yale University, New Haven, Connecticut 06520
| | - Jinrui Xu
- Program in Computational Biology and Bioinformatics, Yale University, New Haven, Connecticut 06520
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520
| | - Koon-Kiu Yan
- Program in Computational Biology and Bioinformatics, Yale University, New Haven, Connecticut 06520
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520
| | - Susan E Celniker
- Division of Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, California 94720
| | - Kevin P White
- Institute for Genomics and Systems Biology, Department of Human Genetics, University of Chicago, Illinois 60637
| | - Lijia Ma
- Institute for Genomics and Systems Biology, Department of Human Genetics, University of Chicago, Illinois 60637
| | - Mark Gerstein
- Program in Computational Biology and Bioinformatics, Yale University, New Haven, Connecticut 06520
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520
- Department of Computer Science, Yale University, New Haven, Connecticut 06520
| | - Valerie Reinke
- Department of Genetics, Yale University, New Haven, Connecticut 06520
| | - Robert H Waterston
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, Washington 98195
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Inukai S, Pincus Z, de Lencastre A, Slack FJ. A microRNA feedback loop regulates global microRNA abundance during aging. RNA (NEW YORK, N.Y.) 2018; 24:159-172. [PMID: 29114017 PMCID: PMC5769744 DOI: 10.1261/rna.062190.117] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Accepted: 10/29/2017] [Indexed: 06/07/2023]
Abstract
Expression levels of many microRNAs (miRNAs) change during aging, notably declining globally in a number of organisms and tissues across taxa. However, little is known about the mechanisms or the biological relevance for this change. We investigated the network of genes that controls miRNA transcription and processing during C. elegans aging. We found that miRNA biogenesis genes are highly networked with transcription factors and aging-associated miRNAs. In particular, miR-71, known to influence life span and itself up-regulated during aging, represses alg-1/Argonaute expression post-transcriptionally during aging. Increased ALG-1 abundance in mir-71 loss-of-function mutants led to globally increased miRNA expression. Interestingly, these mutants demonstrated widespread mRNA expression dysregulation and diminished levels of variability both in gene expression and in overall life span. Thus, the progressive molecular decline often thought to be the result of accumulated damage over an organism's life may be partially explained by a miRNA-directed mechanism of age-associated decline.
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Affiliation(s)
- Sachi Inukai
- Department of Molecular, Cellular and Developmental Biology, Yale University, P.O. Box 208103, New Haven, Connecticut 06520, USA
- Institute for RNA Medicine, Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215, USA
| | - Zachary Pincus
- Department of Developmental Biology
- Department of Genetics, Washington University School of Medicine, St. Louis, Missouri 63110, USA
| | - Alexandre de Lencastre
- Department of Molecular, Cellular and Developmental Biology, Yale University, P.O. Box 208103, New Haven, Connecticut 06520, USA
| | - Frank J Slack
- Department of Molecular, Cellular and Developmental Biology, Yale University, P.O. Box 208103, New Haven, Connecticut 06520, USA
- Institute for RNA Medicine, Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215, USA
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28
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Murray JI. Systems biology of embryonic development: Prospects for a complete understanding of the Caenorhabditis elegans embryo. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2018; 7:e314. [PMID: 29369536 DOI: 10.1002/wdev.314] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Revised: 12/01/2017] [Accepted: 12/12/2017] [Indexed: 01/07/2023]
Abstract
The convergence of developmental biology and modern genomics tools brings the potential for a comprehensive understanding of developmental systems. This is especially true for the Caenorhabditis elegans embryo because its small size, invariant developmental lineage, and powerful genetic and genomic tools provide the prospect of a cellular resolution understanding of messenger RNA (mRNA) expression and regulation across the organism. We describe here how a systems biology framework might allow large-scale determination of the embryonic regulatory relationships encoded in the C. elegans genome. This framework consists of two broad steps: (a) defining the "parts list"-all genes expressed in all cells at each time during development and (b) iterative steps of computational modeling and refinement of these models by experimental perturbation. Substantial progress has been made towards defining the parts list through imaging methods such as large-scale green fluorescent protein (GFP) reporter analysis. Imaging results are now being augmented by high-resolution transcriptome methods such as single-cell RNA sequencing, and it is likely the complete expression patterns of all genes across the embryo will be known within the next few years. In contrast, the modeling and perturbation experiments performed so far have focused largely on individual cell types or genes, and improved methods will be needed to expand them to the full genome and organism. This emerging comprehensive map of embryonic expression and regulatory function will provide a powerful resource for developmental biologists, and would also allow scientists to ask questions not accessible without a comprehensive picture. This article is categorized under: Invertebrate Organogenesis > Worms Technologies > Analysis of the Transcriptome Gene Expression and Transcriptional Hierarchies > Gene Networks and Genomics.
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Affiliation(s)
- John Isaac Murray
- Department of Genetics, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
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29
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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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30
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Angeles-Albores D, Leighton DHW, Tsou T, Khaw TH, Antoshechkin I, Sternberg PW. The Caenorhabditis elegans Female-Like State: Decoupling the Transcriptomic Effects of Aging and Sperm Status. G3 (BETHESDA, MD.) 2017; 7:2969-2977. [PMID: 28751504 PMCID: PMC5592924 DOI: 10.1534/g3.117.300080] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Accepted: 07/04/2017] [Indexed: 12/22/2022]
Abstract
Understanding genome and gene function in a whole organism requires us to fully comprehend the life cycle and the physiology of the organism in question. Caenorhabditis elegans XX animals are hermaphrodites that exhaust their sperm after 3 d of egg-laying. Even though C. elegans can live for many days after cessation of egg-laying, the molecular physiology of this state has not been as intensely studied as other parts of the life cycle, despite documented changes in behavior and metabolism. To study the effects of sperm depletion and aging of C. elegans during the first 6 d of adulthood, we measured the transcriptomes of first-day adult hermaphrodites and sixth-day sperm-depleted adults, and, at the same time points, mutant fog-2(lf) worms that have a feminized germline phenotype. We found that we could separate the effects of biological aging from sperm depletion. For a large subset of genes, young adult fog-2(lf) animals had the same gene expression changes as sperm-depleted sixth-day wild-type hermaphrodites, and these genes did not change expression when fog-2(lf) females reached the sixth day of adulthood. Taken together, this indicates that changing sperm status causes a change in the internal state of the worm, which we call the female-like state. Our data provide a high-quality picture of the changes that happen in global gene expression throughout the period of early aging in the worm.
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Affiliation(s)
- David Angeles-Albores
- Department of Biology and Biological Engineering, and Howard Hughes Medical Institute, Caltech, Pasadena, California 91125
| | - Daniel H W Leighton
- Department of Biology and Biological Engineering, and Howard Hughes Medical Institute, Caltech, Pasadena, California 91125
- Department of Human Genetics, Department of Biological Chemistry, and Howard Hughes Medical Institute, University of California, Los Angeles, California 90095
| | - Tiffany Tsou
- Department of Biology and Biological Engineering, and Howard Hughes Medical Institute, Caltech, Pasadena, California 91125
| | - Tiffany H Khaw
- Department of Biology and Biological Engineering, and Howard Hughes Medical Institute, Caltech, Pasadena, California 91125
| | - Igor Antoshechkin
- Department of Biology and Biological Engineering, Caltech, Pasadena, California 91125
| | - Paul W Sternberg
- Department of Biology and Biological Engineering, and Howard Hughes Medical Institute, Caltech, Pasadena, California 91125
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31
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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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32
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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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33
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Intron-specific patterns of divergence of lin-11 regulatory function in the C. elegans nervous system. Dev Biol 2017; 424:90-103. [DOI: 10.1016/j.ydbio.2017.02.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2017] [Revised: 02/08/2017] [Accepted: 02/12/2017] [Indexed: 12/19/2022]
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34
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Sin O, de Jong T, Mata-Cabana A, Kudron M, Zaini MA, Aprile FA, Seinstra RI, Stroo E, Prins RW, Martineau CN, Wang HH, Hogewerf W, Steinhof A, Wanker EE, Vendruscolo M, Calkhoven CF, Reinke V, Guryev V, Nollen EAA. Identification of an RNA Polymerase III Regulator Linked to Disease-Associated Protein Aggregation. Mol Cell 2017; 65:1096-1108.e6. [PMID: 28306505 PMCID: PMC5364375 DOI: 10.1016/j.molcel.2017.02.022] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 01/05/2017] [Accepted: 02/22/2017] [Indexed: 11/24/2022]
Abstract
Protein aggregation is associated with age-related neurodegenerative disorders, such as Alzheimer's and polyglutamine diseases. As a causal relationship between protein aggregation and neurodegeneration remains elusive, understanding the cellular mechanisms regulating protein aggregation will help develop future treatments. To identify such mechanisms, we conducted a forward genetic screen in a C. elegans model of polyglutamine aggregation and identified the protein MOAG-2/LIR-3 as a driver of protein aggregation. In the absence of polyglutamine, MOAG-2/LIR-3 regulates the RNA polymerase III-associated transcription of small non-coding RNAs. This regulation is lost in the presence of polyglutamine, which mislocalizes MOAG-2/LIR-3 from the nucleus to the cytosol. We then show biochemically that MOAG-2/LIR-3 can also catalyze the aggregation of polyglutamine-expanded huntingtin. These results suggest that polyglutamine can induce an aggregation-promoting activity of MOAG-2/LIR-3 in the cytosol. The concept that certain aggregation-prone proteins can convert other endogenous proteins into drivers of aggregation and toxicity adds to the understanding of how cellular homeostasis can be deteriorated in protein misfolding diseases.
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Affiliation(s)
- Olga Sin
- European Research Institute for the Biology of Ageing, University of Groningen, University Medical Centre Groningen, 9700 AD Groningen, the Netherlands; Graduate Program in Areas of Basic and Applied Biology, Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, 4050-313 Porto, Portugal
| | - Tristan de Jong
- European Research Institute for the Biology of Ageing, University of Groningen, University Medical Centre Groningen, 9700 AD Groningen, the Netherlands
| | - Alejandro Mata-Cabana
- European Research Institute for the Biology of Ageing, University of Groningen, University Medical Centre Groningen, 9700 AD Groningen, the Netherlands
| | - Michelle Kudron
- Department of Genetics, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Mohamad Amr Zaini
- European Research Institute for the Biology of Ageing, University of Groningen, University Medical Centre Groningen, 9700 AD Groningen, the Netherlands
| | | | - Renée I Seinstra
- European Research Institute for the Biology of Ageing, University of Groningen, University Medical Centre Groningen, 9700 AD Groningen, the Netherlands
| | - Esther Stroo
- European Research Institute for the Biology of Ageing, University of Groningen, University Medical Centre Groningen, 9700 AD Groningen, the Netherlands
| | - Roméo Willinge Prins
- European Research Institute for the Biology of Ageing, University of Groningen, University Medical Centre Groningen, 9700 AD Groningen, the Netherlands
| | - Céline N Martineau
- European Research Institute for the Biology of Ageing, University of Groningen, University Medical Centre Groningen, 9700 AD Groningen, the Netherlands
| | - Hai Hui Wang
- European Research Institute for the Biology of Ageing, University of Groningen, University Medical Centre Groningen, 9700 AD Groningen, the Netherlands
| | - Wytse Hogewerf
- European Research Institute for the Biology of Ageing, University of Groningen, University Medical Centre Groningen, 9700 AD Groningen, the Netherlands
| | - Anne Steinhof
- Max Delbrück Center for Molecular Medicine, 13125 Berlin, Germany
| | - Erich E Wanker
- Max Delbrück Center for Molecular Medicine, 13125 Berlin, Germany
| | | | - Cornelis F Calkhoven
- European Research Institute for the Biology of Ageing, University of Groningen, University Medical Centre Groningen, 9700 AD Groningen, the Netherlands
| | - Valerie Reinke
- Department of Genetics, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Victor Guryev
- European Research Institute for the Biology of Ageing, University of Groningen, University Medical Centre Groningen, 9700 AD Groningen, the Netherlands.
| | - Ellen A A Nollen
- European Research Institute for the Biology of Ageing, University of Groningen, University Medical Centre Groningen, 9700 AD Groningen, the Netherlands.
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35
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Starvation-Induced Stress Response Is Critically Impacted by Ceramide Levels in Caenorhabditis elegans. Genetics 2016; 205:775-785. [PMID: 27974500 DOI: 10.1534/genetics.116.194282] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Accepted: 12/07/2016] [Indexed: 12/24/2022] Open
Abstract
Our understanding of the cellular mechanisms by which animals regulate their response to starvation is limited, despite the strong relevance of the problem to major human health issues. The L1 diapause of Caenorhabditis elegans, where first-stage larvae arrest in response to a food-less environment, is an excellent system to study this mechanism. We found, through genetic manipulation and lipid analysis, that biosynthesis of ceramide, particularly those with longer fatty acid side chains, critically impacts animal survival during L1 diapause. Genetic interaction analysis suggests that ceramide may act in both insulin-IGF-1 signaling (IIS)-dependent and IIS-independent pathways to affect starvation survival. Genetic and expression analyses indicate that ceramide is required for maintaining the proper expression of previously characterized starvation-responsive genes, genes that are regulated by the IIS pathway and tumor suppressor Rb, and genes responsive to pathogen. These findings provide an important insight into the roles of sphingolipid metabolism, not only in starvation response, but also in aging and food-response-related human health problems.
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36
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Fuxman Bass JI, Reece-Hoyes JS, Walhout AJ. Gene-Centered Yeast One-Hybrid Assays. Cold Spring Harb Protoc 2016; 2016:2016/12/pdb.top077669. [PMID: 27934693 PMCID: PMC5443116 DOI: 10.1101/pdb.top077669] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
An important question when studying gene regulation is which transcription factors (TFs) interact with which cis-regulatory elements, such as promoters and enhancers. Addressing this issue in complex multicellular organisms is challenging as several hundreds of TFs and thousands of regulatory elements must be considered in the context of different tissues and physiological conditions. Yeast one-hybrid (Y1H) assays provide a powerful "gene-centered" method to identify the TFs that can bind a DNA sequence of interest. In this introduction, we describe the basic principles of the Y1H assay and its advantages and disadvantages and briefly discuss how it is complementary to "TF-centered" methods that identify protein-DNA interactions for a known protein of interest.
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Affiliation(s)
- Juan I. Fuxman Bass
- Program in Systems Biology, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - John S. Reece-Hoyes
- Program in Systems Biology, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Albertha J.M. Walhout
- Program in Systems Biology, University of Massachusetts Medical School, Worcester, Massachusetts 01605
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37
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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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Wang D, He F, Maslov S, Gerstein M. DREISS: Using State-Space Models to Infer the Dynamics of Gene Expression Driven by External and Internal Regulatory Networks. PLoS Comput Biol 2016; 12:e1005146. [PMID: 27760135 PMCID: PMC5070849 DOI: 10.1371/journal.pcbi.1005146] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 09/15/2016] [Indexed: 11/26/2022] Open
Abstract
Gene expression is controlled by the combinatorial effects of regulatory factors from different biological subsystems such as general transcription factors (TFs), cellular growth factors and microRNAs. A subsystem’s gene expression may be controlled by its internal regulatory factors, exclusively, or by external subsystems, or by both. It is thus useful to distinguish the degree to which a subsystem is regulated internally or externally–e.g., how non-conserved, species-specific TFs affect the expression of conserved, cross-species genes during evolution. We developed a computational method (DREISS, dreiss.gerteinlab.org) for analyzing the Dynamics of gene expression driven by Regulatory networks, both External and Internal based on State Space models. Given a subsystem, the “state” and “control” in the model refer to its own (internal) and another subsystem’s (external) gene expression levels. The state at a given time is determined by the state and control at a previous time. Because typical time-series data do not have enough samples to fully estimate the model’s parameters, DREISS uses dimensionality reduction, and identifies canonical temporal expression trajectories (e.g., degradation, growth and oscillation) representing the regulatory effects emanating from various subsystems. To demonstrate capabilities of DREISS, we study the regulatory effects of evolutionarily conserved vs. divergent TFs across distant species. In particular, we applied DREISS to the time-series gene expression datasets of C. elegans and D. melanogaster during their embryonic development. We analyzed the expression dynamics of the conserved, orthologous genes (orthologs), seeing the degree to which these can be accounted for by orthologous (internal) versus species-specific (external) TFs. We found that between two species, the orthologs have matched, internally driven expression patterns but very different externally driven ones. This is particularly true for genes with evolutionarily ancient functions (e.g. the ribosomal proteins), in contrast to those with more recently evolved functions (e.g., cell-cell communication). This suggests that despite striking morphological differences, some fundamental embryonic-developmental processes are still controlled by ancient regulatory systems. The dynamics of a biological system can be controlled by its own internal mechanisms and external perturbations. To gain intuition on this, we may draw a comparison with a mass hanging from a spring. The mass will move naturally by itself but its dynamics is also affected by one’s pulling it. That is, the dynamics of the mass is governed by the effect of the external perturbations superimposed on the internal mechanism of the spring (i.e. Hooke’s law). Similarly, given a group of genes, their temporal gene expression dynamics can be controlled by both transcription factors inside the group and external regulatory factors. Therefore, it is useful to identify the expression dynamics that are exclusively controlled by internal or external factors and compare them across various systems. While state-space models have been widely used to decouple the internal and external effects in physical systems, such as the mass and spring, typical biological systems do not have enough time samples to infer all the model’s parameters, and applications of state-space models were not very effective in these instances. Hence, we developed a general-purpose computational method by integrating state-space models and dimensionality reduction to identify temporal gene expression patterns driven by internal and external regulatory networks. We applied our method to the embryonic developmental datasets in the worm and fly (and also in a human cancer context). We successfully identified the temporal expression dynamics of cross-species conserved genes that were driven by conserved and species-specific regulatory networks.
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Affiliation(s)
- Daifeng Wang
- Department of Biomedical Informatics, Stony Brook University, Stony Brook, New York, United States of America
- Stony Brook Cancer Center, Stony Brook Medicine, Stony Brook, New York, United States of America
| | - Fei He
- Biology Department, Brookhaven National Laboratory, Upton, New York, United States of America
| | - Sergei Maslov
- Biology Department, Brookhaven National Laboratory, Upton, New York, United States of America
- Department of Bioengineering and Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| | - Mark Gerstein
- Program in Computational Biology and Bioinformatics, Yale University, New Haven, Connecticut, United States of America
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, United States of America
- Department of Computer Science, Yale University, New Haven, Connecticut, United States of America
- * E-mail:
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39
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Gendrel M, Atlas EG, Hobert O. A cellular and regulatory map of the GABAergic nervous system of C. elegans. eLife 2016; 5. [PMID: 27740909 PMCID: PMC5065314 DOI: 10.7554/elife.17686] [Citation(s) in RCA: 107] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Accepted: 08/22/2016] [Indexed: 12/16/2022] Open
Abstract
Neurotransmitter maps are important complements to anatomical maps and represent an invaluable resource to understand nervous system function and development. We report here a comprehensive map of neurons in the C. elegans nervous system that contain the neurotransmitter GABA, revealing twice as many GABA-positive neuron classes as previously reported. We define previously unknown glia-like cells that take up GABA, as well as 'GABA uptake neurons' which do not synthesize GABA but take it up from the extracellular environment, and we map the expression of previously uncharacterized ionotropic GABA receptors. We use the map of GABA-positive neurons for a comprehensive analysis of transcriptional regulators that define the GABA phenotype. We synthesize our findings of specification of GABAergic neurons with previous reports on the specification of glutamatergic and cholinergic neurons into a nervous system-wide regulatory map which defines neurotransmitter specification mechanisms for more than half of all neuron classes in C. elegans. DOI:http://dx.doi.org/10.7554/eLife.17686.001
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Affiliation(s)
- Marie Gendrel
- Department of Biological Sciences, Howard Hughes Medical Institute, Columbia University, New York, United States
| | - Emily G Atlas
- Department of Biological Sciences, Howard Hughes Medical Institute, Columbia University, New York, United States
| | - Oliver Hobert
- Department of Biological Sciences, Howard Hughes Medical Institute, Columbia University, New York, United States
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40
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Abstract
A clear definition of what constitutes “Big Data” is difficult to identify, but we find it most useful to define Big Data as a data collection that is complete. By this criterion, researchers on Caenorhabditis elegans have a long history of collecting Big Data, since the organism was selected with the idea of obtaining a complete biological description and understanding of development. The complete wiring diagram of the nervous system, the complete cell lineage, and the complete genome sequence provide a framework to phrase and test hypotheses. Given this history, it might be surprising that the number of “complete” data sets for this organism is actually rather small—not because of lack of effort, but because most types of biological experiments are not currently amenable to complete large-scale data collection. Many are also not inherently limited, so that it becomes difficult to even define completeness. At present, we only have partial data on mutated genes and their phenotypes, gene expression, and protein–protein interaction—important data for many biological questions. Big Data can point toward unexpected correlations, and these unexpected correlations can lead to novel investigations; however, Big Data cannot establish causation. As a result, there is much excitement about Big Data, but there is also a discussion on just what Big Data contributes to solving a biological problem. Because of its relative simplicity, C. elegans is an ideal test bed to explore this issue and at the same time determine what is necessary to build a multicellular organism from a single cell.
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Affiliation(s)
- Harald Hutter
- Department of Biological Sciences, Simon Fraser University, Burnaby, BC V5A 1S6, Canada
| | - Donald Moerman
- Department of Zoology, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
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41
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Cell-Autonomous and Non-Cell-Autonomous Regulation of a Feeding State-Dependent Chemoreceptor Gene via MEF-2 and bHLH Transcription Factors. PLoS Genet 2016; 12:e1006237. [PMID: 27487365 PMCID: PMC4972359 DOI: 10.1371/journal.pgen.1006237] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Accepted: 07/12/2016] [Indexed: 01/01/2023] Open
Abstract
Food and feeding-state dependent changes in chemoreceptor gene expression may allow Caenorhabditis elegans to modify their chemosensory behavior, but the mechanisms essential for these expression changes remain poorly characterized. We had previously shown that expression of a feeding state-dependent chemoreceptor gene, srh-234, in the ADL sensory neuron of C. elegans is regulated via the MEF-2 transcription factor. Here, we show that MEF-2 acts together with basic helix-loop-helix (bHLH) transcription factors to regulate srh-234 expression as a function of feeding state. We identify a cis-regulatory MEF2 binding site that is necessary and sufficient for the starvation-induced down regulation of srh-234 expression, while an E-box site known to bind bHLH factors is required to drive srh-234 expression in ADL. We show that HLH-2 (E/Daughterless), HLH-3 and HLH-4 (Achaete-scute homologs) act in ADL neurons to regulate srh-234 expression. We further demonstrate that the expression levels of srh-234 in ADL neurons are regulated remotely by MXL-3 (Max-like 3 homolog) and HLH-30 (TFEB ortholog) acting in the intestine, which is dependent on insulin signaling functioning specifically in ADL neurons. We also show that this intestine-to-neuron feeding-state regulation of srh-234 involves a subset of insulin-like peptides. These results combined suggest that chemoreceptor gene expression is regulated by both cell-autonomous and non-cell-autonomous transcriptional mechanisms mediated by MEF2 and bHLH factors, which may allow animals to fine-tune their chemosensory responses in response to changes in their feeding state. Plasticity in chemoreceptor gene expression may be a simple strategy by which an animal can modulate its chemosensory responses in changing external and internal state conditions. However, the transcriptional mechanisms required for these chemoreceptor gene expression changes are poorly understood. Here, we describe the identification of a transcriptional module(s) consisting of MEF-2 and basic helix-loop-helix (bHLH) transcription factors and their cognate binding sites in Caenorhabditis elegans that act together in ADL sensory neurons to properly regulate expression of a feeding-state dependent chemoreceptor gene. We also showed that chemoreceptor gene expression in ADL neurons are regulated remotely by bHLH factors acting in the intestine through an insulin-mediated signaling pathway, implying a sensory neuron-gut interaction for modulating chemoreceptor gene expression as a function of feeding state. This work describes transcriptional mechanisms mediated by MEF-2 and bHLH factors by which the expression of individual chemoreceptor genes in C. elegans are changed in response to changes in feeding state conditions.
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42
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Schmitz JF, Zimmer F, Bornberg-Bauer E. Mechanisms of transcription factor evolution in Metazoa. Nucleic Acids Res 2016; 44:6287-97. [PMID: 27288445 PMCID: PMC5291267 DOI: 10.1093/nar/gkw492] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Revised: 05/18/2016] [Accepted: 05/22/2016] [Indexed: 11/12/2022] Open
Abstract
Transcriptions factors (TFs) are pivotal for the regulation of virtually all cellular processes, including growth and development. Expansions of TF families are causally linked to increases in organismal complexity. Here we study the evolutionary dynamics, genetic causes and functional implications of the five largest metazoan TF families. We find that family expansions dominate across the whole metazoan tree; however, some branches experience exceptional family-specific accelerated expansions. Additionally, we find that such expansions are often predated by modular domain rearrangements, which spur the expansion of a new sub-family by separating it from the rest of the TF family in terms of protein-protein interactions. This separation allows for radical shifts in the functional spectrum of a duplicated TF. We also find functional differentiation inside TF sub-families as changes in expression specificity. Furthermore, accelerated family expansions are facilitated by repeats of sequence motifs such as C2H2 zinc fingers. We quantify whole genome duplications and single gene duplications as sources of TF family expansions, implying that some, but not all, TF duplicates are preferentially retained. We conclude that trans-regulatory changes (domain rearrangements) are instrumental for fundamental functional innovations, that cis-regulatory changes (affecting expression) accomplish wide-spread fine tuning and both jointly contribute to the functional diversification of TFs.
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Affiliation(s)
- Jonathan F Schmitz
- Evolutionary Bioinformatics Group, Institute for Evolution and Biodiversity, Hüfferstrasse 1, D-48149 Münster, Germany
| | - Fabian Zimmer
- Evolutionary Bioinformatics Group, Institute for Evolution and Biodiversity, Hüfferstrasse 1, D-48149 Münster, Germany Department of Genetics, Evolution and Environment, University College London, London WC1E 6BT, UK
| | - Erich Bornberg-Bauer
- Evolutionary Bioinformatics Group, Institute for Evolution and Biodiversity, Hüfferstrasse 1, D-48149 Münster, Germany
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43
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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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44
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Isakova A, Berset Y, Hatzimanikatis V, Deplancke B. Quantification of Cooperativity in Heterodimer-DNA Binding Improves the Accuracy of Binding Specificity Models. J Biol Chem 2016; 291:10293-306. [PMID: 26912662 PMCID: PMC4858977 DOI: 10.1074/jbc.m115.691154] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Revised: 02/18/2016] [Indexed: 12/31/2022] Open
Abstract
Many transcription factors (TFs) have the ability to cooperate on DNA elements as heterodimers. Despite the significance of TF heterodimerization for gene regulation, a quantitative understanding of cooperativity between various TF dimer partners and its impact on heterodimer DNA binding specificity models is still lacking. Here, we used a novel integrative approach, combining microfluidics-steered measurements of dimer-DNA assembly with mechanistic modeling of the implicated protein-protein-DNA interactions to quantitatively interrogate the cooperative DNA binding behavior of the adipogenic peroxisome proliferator-activated receptor γ (PPARγ):retinoid X receptor α (RXRα) heterodimer. Using the high throughput MITOMI (mechanically induced trapping of molecular interactions) platform, we derived equilibrium DNA binding data for PPARγ, RXRα, as well as the PPARγ:RXRα heterodimer to more than 300 target DNA sites and variants thereof. We then quantified cooperativity underlying heterodimer-DNA binding and derived an integrative heterodimer DNA binding constant. Using this cooperativity-inclusive constant, we were able to build a heterodimer-DNA binding specificity model that has superior predictive power than the one based on a regular one-site equilibrium. Our data further revealed that individual nucleotide substitutions within the target site affect the extent of cooperativity in PPARγ:RXRα-DNA binding. Our study therefore emphasizes the importance of assessing cooperativity when generating DNA binding specificity models for heterodimers.
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Affiliation(s)
- Alina Isakova
- From the Institute of Bioengineering, Swiss Institute of Bioinformatics (SIB), CH-1015 Lausanne, Switzerland
| | - Yves Berset
- From the Institute of Bioengineering, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne, and Swiss Institute of Bioinformatics (SIB), CH-1015 Lausanne, Switzerland
| | - Vassily Hatzimanikatis
- Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne, and Swiss Institute of Bioinformatics (SIB), CH-1015 Lausanne, Switzerland
| | - Bart Deplancke
- From the Institute of Bioengineering, Swiss Institute of Bioinformatics (SIB), CH-1015 Lausanne, Switzerland
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45
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Yen CA, Curran SP. Gene-diet interactions and aging in C. elegans. Exp Gerontol 2016; 86:106-112. [PMID: 26924670 DOI: 10.1016/j.exger.2016.02.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Revised: 02/16/2016] [Accepted: 02/24/2016] [Indexed: 02/06/2023]
Abstract
Diet is the most variable aspect of life history, as most individuals have a large diversity of food choices, varying in the type and amount that they ingest. In the short-term, diet can affect metabolism and energy levels. However, in the long run, the net deficiency or excess of calories from diet can influence the progression and severity of age-related diseases. An old and yet still debated question is: how do specific dietary choices impact health- and lifespan? It is clear that genetics can play a critical role - perhaps just as important as diet choices. For example, poor diet in combination with genetic susceptibility can lead to metabolic disorders, such as obesity and type 2 diabetes. Recent work in Caenorhabditis elegans has identified the existence of diet-gene pairs, where the consequence of mutating a specific gene is only realized on specific diets. Many core metabolic pathways are conserved from worm to human. Although only a handful of these diet-gene pairs has been characterized, there are potentially hundreds, if not thousands, of such interactions, which may explain the variability in the rates of aging in humans and the incidence and severity of age-related diseases.
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Affiliation(s)
- Chia An Yen
- University of Southern California, Dornsife College of Letters, Arts, and Science, Department of Molecular and Computational Biology, United States
| | - Sean P Curran
- University of Southern California, Dornsife College of Letters, Arts, and Science, Department of Molecular and Computational Biology, United States; University of Southern California, Davis School of Gerontology, United States.
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46
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47
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MacNeil LT, Pons C, Arda HE, Giese GE, Myers CL, Walhout AJM. Transcription Factor Activity Mapping of a Tissue-Specific in vivo Gene Regulatory Network. Cell Syst 2015; 1:152-162. [PMID: 26430702 DOI: 10.1016/j.cels.2015.08.003] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
A wealth of physical interaction data between transcription factors (TFs) and DNA has been generated, but these interactions often do not have apparent regulatory consequences. Thus, equating physical interaction data with gene regulatory networks (GRNs) is problematic. Here, we comprehensively assay TF activity, rather than binding, to construct a network of gene regulatory interactions in the C. elegans intestine. By manually observing the in vivo tissue-specific knockdown of 921 TFs on a panel of 19 fluorescent transcriptional reporters, we identified a GRN of 411 interactions between 19 promoters and 177 TFs. This GRN shows only modest overlap with physical interactions, indicating that many regulatory interactions are indirect. We applied nested effects modeling to uncover information flow between TFs in the intestine that converges on a small set of physical TF-promoter interactions. We found numerous cell nonautonomous regulatory interactions, illustrating tissue-to-tissue communication. Altogether, our study illuminates the complexity of gene regulation in the context of a living animal.
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Affiliation(s)
- Lesley T MacNeil
- 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
| | - Carles Pons
- Department of Computer Science and Engineering, University of Minnesota-Twin Cities, Minneapolis, MN 55455, USA
| | - H Efsun Arda
- 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
| | - Gabrielle E Giese
- Program in Systems Biology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Chad L Myers
- Department of Computer Science and Engineering, University of Minnesota-Twin Cities, Minneapolis, MN 55455, 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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48
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Hench J, Henriksson J, Abou-Zied AM, Lüppert M, Dethlefsen J, Mukherjee K, Tong YG, Tang L, Gangishetti U, Baillie DL, Bürglin TR. The Homeobox Genes of Caenorhabditis elegans and Insights into Their Spatio-Temporal Expression Dynamics during Embryogenesis. PLoS One 2015; 10:e0126947. [PMID: 26024448 PMCID: PMC4448998 DOI: 10.1371/journal.pone.0126947] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2015] [Accepted: 04/09/2015] [Indexed: 11/18/2022] Open
Abstract
Homeobox genes play crucial roles for the development of multicellular eukaryotes. We have generated a revised list of all homeobox genes for Caenorhabditis elegans and provide a nomenclature for the previously unnamed ones. We show that, out of 103 homeobox genes, 70 are co-orthologous to human homeobox genes. 14 are highly divergent, lacking an obvious ortholog even in other Caenorhabditis species. One of these homeobox genes encodes 12 homeodomains, while three other highly divergent homeobox genes encode a novel type of double homeodomain, termed HOCHOB. To understand how transcription factors regulate cell fate during development, precise spatio-temporal expression data need to be obtained. Using a new imaging framework that we developed, Endrov, we have generated spatio-temporal expression profiles during embryogenesis of over 60 homeobox genes, as well as a number of other developmental control genes using GFP reporters. We used dynamic feedback during recording to automatically adjust the camera exposure time in order to increase the dynamic range beyond the limitations of the camera. We have applied the new framework to examine homeobox gene expression patterns and provide an analysis of these patterns. The methods we developed to analyze and quantify expression data are not only suitable for C. elegans, but can be applied to other model systems or even to tissue culture systems.
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Affiliation(s)
- Jürgen Hench
- Dept. of Biosciences and Nutrition & Center for Biosciences, Karolinska Institutet, Hälsovägen 7, Novum, SE-141 83, Huddinge, Sweden
- School of Life Sciences, Södertörns Högskola, Huddinge, Sweden
| | - Johan Henriksson
- Dept. of Biosciences and Nutrition & Center for Biosciences, Karolinska Institutet, Hälsovägen 7, Novum, SE-141 83, Huddinge, Sweden
- School of Life Sciences, Södertörns Högskola, Huddinge, Sweden
| | - Akram M. Abou-Zied
- Dept. of Biosciences and Nutrition & Center for Biosciences, Karolinska Institutet, Hälsovägen 7, Novum, SE-141 83, Huddinge, Sweden
- School of Life Sciences, Södertörns Högskola, Huddinge, Sweden
| | - Martin Lüppert
- Dept. of Biosciences and Nutrition & Center for Biosciences, Karolinska Institutet, Hälsovägen 7, Novum, SE-141 83, Huddinge, Sweden
- School of Life Sciences, Södertörns Högskola, Huddinge, Sweden
| | - Johan Dethlefsen
- Dept. of Biosciences and Nutrition & Center for Biosciences, Karolinska Institutet, Hälsovägen 7, Novum, SE-141 83, Huddinge, Sweden
- School of Life Sciences, Södertörns Högskola, Huddinge, Sweden
| | - Krishanu Mukherjee
- Dept. of Biosciences and Nutrition & Center for Biosciences, Karolinska Institutet, Hälsovägen 7, Novum, SE-141 83, Huddinge, Sweden
- School of Life Sciences, Södertörns Högskola, Huddinge, Sweden
| | - Yong Guang Tong
- Dept. of Biosciences and Nutrition & Center for Biosciences, Karolinska Institutet, Hälsovägen 7, Novum, SE-141 83, Huddinge, Sweden
- School of Life Sciences, Södertörns Högskola, Huddinge, Sweden
| | - Lois Tang
- Dept. of Biosciences and Nutrition & Center for Biosciences, Karolinska Institutet, Hälsovägen 7, Novum, SE-141 83, Huddinge, Sweden
- School of Life Sciences, Södertörns Högskola, Huddinge, Sweden
| | - Umesh Gangishetti
- Dept. of Biosciences and Nutrition & Center for Biosciences, Karolinska Institutet, Hälsovägen 7, Novum, SE-141 83, Huddinge, Sweden
| | - David L. Baillie
- Dept. of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia, V5A 1S6, Canada
| | - Thomas R. Bürglin
- Dept. of Biosciences and Nutrition & Center for Biosciences, Karolinska Institutet, Hälsovägen 7, Novum, SE-141 83, Huddinge, Sweden
- School of Life Sciences, Södertörns Högskola, Huddinge, Sweden
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49
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Kaneko I, Iwanaga S, Kato T, Kobayashi I, Yuda M. Genome-Wide Identification of the Target Genes of AP2-O, a Plasmodium AP2-Family Transcription Factor. PLoS Pathog 2015; 11:e1004905. [PMID: 26018192 PMCID: PMC4446032 DOI: 10.1371/journal.ppat.1004905] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Accepted: 04/21/2015] [Indexed: 12/20/2022] Open
Abstract
Stage-specific transcription is a fundamental biological process in the life cycle of the Plasmodium parasite. Proteins containing the AP2 DNA-binding domain are responsible for stage-specific transcriptional regulation and belong to the only known family of transcription factors in Plasmodium parasites. Comprehensive identification of their target genes will advance our understanding of the molecular basis of stage-specific transcriptional regulation and stage-specific parasite development. AP2-O is an AP2 family transcription factor that is expressed in the mosquito midgut-invading stage, called the ookinete, and is essential for normal morphogenesis of this stage. In this study, we identified the genome-wide target genes of AP2-O by chromatin immunoprecipitation-sequencing and elucidate how this AP2 family transcription factor contributes to the formation of this motile stage. The analysis revealed that AP2-O binds specifically to the upstream genomic regions of more than 500 genes, suggesting that approximately 10% of the parasite genome is directly regulated by AP2-O. These genes are involved in distinct biological processes such as morphogenesis, locomotion, midgut penetration, protection against mosquito immunity and preparation for subsequent oocyst development. This direct and global regulation by AP2-O provides a model for gene regulation in Plasmodium parasites and may explain how these parasites manage to control their complex life cycle using a small number of sequence-specific AP2 transcription factors. Although malarial parasites have a complex life cycle, they harbor only 30 transcription factors in their genome. The majority of these transcription factors belong to a single family referred to as the AP2 family. Our previous study suggested that stage-specific AP2 family transcription factors have critical roles in maintaining the Plasmodium parasite life cycle. However, it remains fairly elusive as to how these transcription factors regulate each stage. AP2-O is an AP2 family transcription factor that is expressed during the mosquito midgut-invading stage, the ookinete, and is essential for normal development of this stage. In the present study, we identified the entire set of AP2-O target genes to elucidate how this AP2 family transcription factor contributes to the formation of this stage. Our results showed that AP2-O directly regulates 10% of the parasite genome and is involved in the whole process of mosquito midgut-invasion by ookinetes. The global and comprehensive regulation by the AP2 family transcription factor that we revealed provides a model for transcriptional regulation of this parasite and may explain how malarial parasites regulate their complex life cycle using a small number of sequence-specific transcription factors.
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Affiliation(s)
- Izumi Kaneko
- Department of Medical Zoology, Mie University Graduate School of Medicine, Tsu, Mie, Japan
| | - Shiroh Iwanaga
- Department of Medical Zoology, Mie University Graduate School of Medicine, Tsu, Mie, Japan
| | - Tomomi Kato
- Department of Medical Zoology, Mie University Graduate School of Medicine, Tsu, Mie, Japan
| | - Issei Kobayashi
- Core-Lab, Graduate School of Regional Innovation Studies, Mie University, Tsu, Mie, Japan
| | - Masao Yuda
- Department of Medical Zoology, Mie University Graduate School of Medicine, Tsu, Mie, Japan
- * E-mail:
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González-Barrios M, Fierro-González JC, Krpelanova E, Mora-Lorca JA, Pedrajas JR, Peñate X, Chavez S, Swoboda P, Jansen G, Miranda-Vizuete A. Cis- and trans-regulatory mechanisms of gene expression in the ASJ sensory neuron of Caenorhabditis elegans. Genetics 2015; 200:123-34. [PMID: 25769980 PMCID: PMC4423358 DOI: 10.1534/genetics.115.176172] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Accepted: 03/11/2015] [Indexed: 01/25/2023] Open
Abstract
The identity of a given cell type is determined by the expression of a set of genes sharing common cis-regulatory motifs and being regulated by shared transcription factors. Here, we identify cis and trans regulatory elements that drive gene expression in the bilateral sensory neuron ASJ, located in the head of the nematode Caenorhabditis elegans. For this purpose, we have dissected the promoters of the only two genes so far reported to be exclusively expressed in ASJ, trx-1 and ssu-1. We hereby identify the ASJ motif, a functional cis-regulatory bipartite promoter region composed of two individual 6 bp elements separated by a 3 bp linker. The first element is a 6 bp CG-rich sequence that presumably binds the Sp family member zinc-finger transcription factor SPTF-1. Interestingly, within the C. elegans nervous system SPTF-1 is also found to be expressed only in ASJ neurons where it regulates expression of other genes in these neurons and ASJ cell fate. The second element of the bipartite motif is a 6 bp AT-rich sequence that is predicted to potentially bind a transcription factor of the homeobox family. Together, our findings identify a specific promoter signature and SPTF-1 as a transcription factor that functions as a terminal selector gene to regulate gene expression in C. elegans ASJ sensory neurons.
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Affiliation(s)
- María González-Barrios
- Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/Consejo Superior de Investigaciones Científicas/Universidad de Sevilla, E-41013 Sevilla, Spain
| | | | - Eva Krpelanova
- Department of Cell Biology, Erasmus MC, 3000 CA Rotterdam, The Netherlands
| | - José Antonio Mora-Lorca
- Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/Consejo Superior de Investigaciones Científicas/Universidad de Sevilla, E-41013 Sevilla, Spain Departamento de Farmacología, Facultad de Farmacia, Universidad de Sevilla, E-41012 Sevilla, Spain
| | - José Rafael Pedrajas
- Grupo de Bioquímica y Señalización Celular, Departamento de Biología Experimental, Universidad de Jaén, E-23071 Jaén, Spain
| | - Xenia Peñate
- Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/Consejo Superior de Investigaciones Científicas/Universidad de Sevilla, E-41013 Sevilla, Spain Departamento de Genética, Facultad de Biología, Universidad de Sevilla, E-41012 Sevilla, Spain
| | - Sebastián Chavez
- Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/Consejo Superior de Investigaciones Científicas/Universidad de Sevilla, E-41013 Sevilla, Spain Departamento de Genética, Facultad de Biología, Universidad de Sevilla, E-41012 Sevilla, Spain
| | - Peter Swoboda
- Karolinska Institute, Department of Biosciences and Nutrition, S-141 83 Huddinge, Sweden
| | - Gert Jansen
- Department of Cell Biology, Erasmus MC, 3000 CA Rotterdam, The Netherlands
| | - Antonio Miranda-Vizuete
- Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/Consejo Superior de Investigaciones Científicas/Universidad de Sevilla, E-41013 Sevilla, Spain
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