Functional Study of the Role Played by Nucleolar Proteins in the Control of Neural Progenitor Homeostasis Using Zebrafish As a Model Alessandro Brombin

Total Page:16

File Type:pdf, Size:1020Kb

Functional Study of the Role Played by Nucleolar Proteins in the Control of Neural Progenitor Homeostasis Using Zebrafish As a Model Alessandro Brombin Functional study of the role played by nucleolar proteins in the control of neural progenitor homeostasis using zebrafish as a model Alessandro Brombin To cite this version: Alessandro Brombin. Functional study of the role played by nucleolar proteins in the control of neural progenitor homeostasis using zebrafish as a model. Molecular biology. Université Paris Sud -Paris XI, 2015. English. NNT : 2015PA112237. tel-01599238 HAL Id: tel-01599238 https://tel.archives-ouvertes.fr/tel-01599238 Submitted on 2 Oct 2017 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. UNIVERSITÉ PARIS-SUD ÉCOLE DOCTORALE 426 : GÈNES GÉNOMES CELLULES Laboratoire : CNRS, UMR 9197, Institut des Neurosciences Paris‐Saclay THÈSE DE DOCTORAT SCIENCES DE LA VIE ET DE LA SANTÉ par Alessandro BROMBIN Functional study of the role played by nucleolar proteins in the control of neural progenitor homeostasis using zebrafish as a model Date de soutenance : 29/09/2015 Composition du jury : Directeur de thèse : Jean-Stéphane JOLY DR1 (INRA) Rapporteurs : Francesco ARGENTON Professeur (Università degli Studi di Padova) Pierre-Emmanuel GLEIZES Professeur (Université de Toulouse – Paul Sabatier) Examinateurs : Pierre CAPY Professeur (Université de Paris Sud) Frédéric CATEZ CR1 (CNRS) Morgane LOCKER MCF (Université de Paris Sud) Membres invités : Françoise JAMEN MCF (Université de Paris Sud) Acknowledgements Because so many people helped me so much during these years, I think I will never be able to express all my gratitude well enough towards everybody and I apologize in advance to people I may have forgotten to mention. To begin, I would like to especially thank Dr. Jean-Stéphane Joly and Dr. Françoise Jamen without whom I would have never settled down in France and I would have possibly never started a thesis after all. Six years ago, you took the decision to bet on a non-French-speaker Italian student and you brought me until here. Thank you for all the support during all these years: for all the meetings, discussions, advice, preparations for presentations, searching for the best strategy to make experiments work and helping me with my written works. Thanks to both of you for never letting go. I must express my special thanks to all the members of my examination committee who readily agreed to participate in the evaluation and defense of my thesis: Prof. Francesco Argenton, Prof. Pierre Capy, Dr. Frédéric Catez, Prof. Pierre-Emmanuel Gleizes, Dr. Morgane Locker. Thank you very much to Francesco Argenton and Pierre-Emmanuel Gleizes who accepted the heavy task of being a “rapporteur” without hesitation. During these years all my colleagues turned into friends and I wish to thank all of them for this. First of all I wish to thank my past and present bureau: we shared so much all together and I consider you as my family. Aurélie, Emilie, Mathilde, Matthieu, Rosaria, Stéphanie and Tibi (in strict alphabetical order) we had never ending discussion about science, thesis, postdoc, fashion, films, series, food and everything. It was a joy to come every day at work. Emilie, thanks because you have been “ma postdoc” and my Timon. Aurélie, thanks for all the things that we shared in the lab and outside (I will miss our gossip dance with the chairs). Matthieu, thanks for being our conscience. Thanks also to my “pote” Joshua. Thanks Rosaria and Stéphanie because you went through my writing period without punching me. Stéphanie and Aurélie, you are my “padawans”: hold on, girls! Thanks to all of you because you forced me to stop being “sentimentalement coincé” (you know that I would have used another term) and made me write these acknowledgements. How to forget the members of the “extended bureau”? I wish to thank Jean-Michel for his precious support, long discussions amazing dinners and wine. Thanks also to Franck for all the scientific discussions. Thanks to Johanna for being always so positive and for laughing as much loud as me (I am still in debt with you), to Pierre for the amazing breaks and for making me feel like a professional chef. I Thanks Lucie for making me feel like a genius, to Barbara for our car discussions and to Maryline for her advices both on my experiments and recipes. Thanks to all the members of the “couloir des fous” (Arnim, Elodie, Laurie, Sylvie, Stéphane, Victor, Adeline, …): I always found help, support and friendship. Thanks to the past and present members of the Amagen unit for technical help, but also for being what you are. I wish to thank Sosthène for being exactly like me, Joanne for our “good morning meetings” before 8 a.m., Naïma for her smile, Sylvia for always remembering that Italy is an amazing place, Zlatko for being my example (I think about you) and Noémie for the many advices and for our beers. Thanks to Fred, Laurent, Ben and Céline. Thanks to all the past and present members of DEPSN/NED/NeuroPSI (yes, I have been part of the three units): Yan and Hélène (my zombie friends), Julia (always helping me), Alex, Olivier, Hélène, Karine, Karen, Raphaël, Jean-Baptiste, Yannick, Ingrid, Audrey, Gaëlle, Yvette. All of you made me feel like home. Now, I must also express my special gratitude to Ludo who welcomed me in his apartment. We fought and we laughed, we cooked and we discussed. For this I thank you! (you know that I will be always ready to start the “coloc 2.0”). Thanks to all my “Parisian” friends: Vale and Andi (always caring about me, even if I disappeared), Marco and Clèm (for having brought a little bit of “Colli” here), Micol, Simone, Elisa, Ale and Anna. Thanks as well to the “non-Parisians” who are in Italy (I always think about you). Finally, I wish to thank my family with a “grazie” : mi avete sempre supportato dall’Italia e non sapete quanto sia stato importante sapervi sempre vicini (finalmente riuscirete anche voi a godervi Parigi come ho fatto io in questi anni). II ABSTRACT In neural stem cells (NSCs) and neural progenitors (NPs), as in other cell types, cell identity is characterized by specific molecular signatures that depend on the environment provided by neighboring cells. Thus, it is important to study progenitor cells in vivo. The zebrafish optic tectum (OT) is a suitable model for that purpose. Indeed, this large structure of the dorsal midbrain displays life-long oriented growth supported by neuroepithelial cells present at its periphery (in the peripheral midbrain layer, PML). Moreover, neuroepithelial progenitors, fast-amplifying progenitors and post-mitotic cells are found in adjacent domains of the OT, as a consequence of its oriented growth. Each cell population is marked by concentric gene expression patterns. Interestingly, a datamining of the ZFIN gene expression database allowed us to identify around 50 genes displaying biased expression in PML cells (neuroepithelial progenitors). Interestingly, many “PML genes” code for ribosome biogenesis factors. The accumulation of transcripts for such ubiquitously expressed genes in SAPs was very surprising so during my thesis I examined whether ribosome biogenesis may have specific roles in these neuroepithelial cells, while improving our knowledge. Indeed, although it is generally admitted that ribosome biogenesis is essential in all cells, it has been shown quite recently that several components of the ribosome biogenesis have tissue restricted roles. For example, Notchless is required for the survival of the inner cell mass in the preimplantation mouse embryo. More recently, conditional knock-out experiments in mice showed that Notchless is necessary for the maintenance of hematopoietic stem cells and intestinal stem cells, but not for committed progenitors and differentiated cells. Indeed in the absence of Notchless in stem cells, the immature 60S subunit cannot be exported from the nucleus and accumulates. This does not happen in differentiated cells where Notchless is dispensable. I started a functional study based on the conditional overexpression of a dominant-negative form of the gene notchless homolog 1 (nle1, the zebrafish homolog of the mammalian gene Notchless). My hypothesis was that the PML slow-amplifying progenitors (SAPs) may require Notchless for the maturation of the 60S subunit, but not the differentiated cells which could survive also after the deletion of this gene. Experiments are still underway. So far we could demonstrate that nle1 has a crucial role in SAPs. I studied zebrafish mutants for genes coding for the components of the box C/D small nucleolar ribonucleoprotein (snoRNP) complex (Fibrillarin, Nop56, Nop58). Mutants displayed a similar phenotype with massive apoptosis and a deregulation of the cell cycle in the whole tectum at 48hpf. Our data suggest a cell cycle arrest at the G2/M transition, highlighting novel possible mechanisms of cell cycle arrest upon impaired ribosome biogenesis. All together, these data highlight how ribosome biogenesis factors and the whole ribosome biogenesis contribute to the fine regulation of cell homeostasis thereby contributing to the determination of progenitor cell identity. III RESUME L’identité des cellules souches et des progéniteurs neuraux, comme celle de tout type cellulaire, est caractérisée par des signatures moléculaires spécifiques qui dépendent de l’environnement dans lesquelles les cellules se trouvent. Ainsi, il est primordial d’étudier ces cellules dans un contexte in vivo. Le toit optique du poisson zèbre est un modèle idéal pour ce type d’étude.
Recommended publications
  • Preclinical Research 2020 Sections
    Sackler Faculty of Medicine Preclinical Research 2020 Sections Cancer and Molecular Therapies 8 Dental Health and Medicine 52 Diabetes, Metabolic and Endocrine Diseases 62 Genomics & Personalized Medicine 78 Hearing, Language & Speech Sciences and Disorders 98 Infectious Diseases 117 Inflammatory and Autoimmune Diseases 137 Medical Education and Ethics 147 Nervous System and Brain Disorders 154 Nursing, Occupational and Physical Therapy 200 Public Health 235 Reproduction, Development and Evolution 263 Stem Cells and Regenerative Medicine 280 Cover images (from bottom left, clockwise): Image 1: Human embryonic stem cell derived cardiomyocytes stained with fluorescent antibodies. The cardiac marker alpha-actinin (green), calcium channel modulator, Ahnak1 (red) – Shimrit Oz, Nathan Dascal. Image 2: Islet of Langerhans containing insulin-producing beta-cells (green) and glucagon- producing alpha-cells (red) – Daria Baer, Limor Landsman. Image 3: β-catenin in C. elegans vulva – Michal Caspi, Limor Broday, Rina Rosin-Arbesfeld. Image 4: Stereocilia of a sensory outer hair cell from a mouse inner ear – Shaked Shivatzki, Karen Avraham. Image 5: Electron scanning micrograph of middle ear ossicles from a mouse ear stained with pseudo colors – Shaked Shivatski, Karen Avraham. Image 6: Resistin-like molecule alpha (red), eosinophil major basic protein (green) and DAPI (blue) staining of asthmatic mice – Danielle Karo-Atar, Ariel Munitz. © All rights reserved Editor: Prof. Karen Avraham Graphic design: Michal Semo Kovetz, TAU Graphic Design Studio February 2020 Sackler Faculty of Medicine Research 2020 2 The Sackler Faculty of Medicine The Sackler Faculty of Medicine is Israel’s largest diabetes, neurodegenerative diseases, infectious medical research and training complex. The Sackler diseases and genetic diseases, including but not Faculty of Medicine of Tel Aviv University (TAU) was imited to Alzheimer’s disease, Parkinson’s disease founded in 1964 following the generous contributions and HIV/AIDS.
    [Show full text]
  • Introduction to the Cell Cell History Cell Structures and Functions
    Introduction to the cell cell history cell structures and functions CK-12 Foundation December 16, 2009 CK-12 Foundation is a non-profit organization with a mission to reduce the cost of textbook materials for the K-12 market both in the U.S. and worldwide. Using an open-content, web-based collaborative model termed the “FlexBook,” CK-12 intends to pioneer the generation and distribution of high quality educational content that will serve both as core text as well as provide an adaptive environment for learning. Copyright ©2009 CK-12 Foundation This work is licensed under the Creative Commons Attribution-Share Alike 3.0 United States License. To view a copy of this license, visit http://creativecommons.org/licenses/by-sa/3.0/us/ or send a letter to Creative Commons, 171 Second Street, Suite 300, San Francisco, California, 94105, USA. Contents 1 Cell structure and function dec 16 5 1.1 Lesson 3.1: Introduction to Cells .................................. 5 3 www.ck12.org www.ck12.org 4 Chapter 1 Cell structure and function dec 16 1.1 Lesson 3.1: Introduction to Cells Lesson Objectives • Identify the scientists that first observed cells. • Outline the importance of microscopes in the discovery of cells. • Summarize what the cell theory proposes. • Identify the limitations on cell size. • Identify the four parts common to all cells. • Compare prokaryotic and eukaryotic cells. Introduction Knowing the make up of cells and how cells work is necessary to all of the biological sciences. Learning about the similarities and differences between cell types is particularly important to the fields of cell biology and molecular biology.
    [Show full text]
  • Creating a Census of Human Cells
    XO FILES SCIENCE eXtraordinary Opportunity PHILANTHROPY ALLIANCE Creating a Census of Human Cells For the first time, new techniques make possible a systematic description of the myriad types of cells in the human body that underlie both health and disease. Aviv Regev Imagine you had a way to cure cancer that involved taking a molecule from a tumor and engineering the body’s immune cells to recognize and kill any cell with that molecule. But before you could apply this approach, you would need to be sure that no healthy cell also expressed that molecule. Given the 20 trillion cells in a human body, how would you do that? This is not a hypothetical example, but was one recently posed to our laboratory. More fundamentally, without a map of different cell types and where they are found within the body, how could you systematically study changes in the map associated with different diseases, or High resolution images of retinal tissue from the human eye, showing ganglion cells (in green). The circular cell body is attached to thin dendrites on which nerve synapses form—in different understand where genes associated with tissue layers depending on the cell type and function. Credit: Lab of Joshua Sanes, Harvard. disease are active in our body or analyze the regulatory mechanisms that govern the production of different cell types, or genetic profile of an individual cell— proteins they use and that information sort out how different cell types combine identifying which genes are turned synthesized with the location into an to form specific tissues? on, actively making proteins.
    [Show full text]
  • The Ribosomal Protein Rpl22 Controls Ribosome Composition by Directly Repressing Expression of Its Own Paralog, Rpl22l1
    The Ribosomal Protein Rpl22 Controls Ribosome Composition by Directly Repressing Expression of Its Own Paralog, Rpl22l1 Monique N. O’Leary1,2, Katherine H. Schreiber1,2, Yong Zhang3, Anne-Ce´cile E. Duc3, Shuyun Rao3,J. Scott Hale4¤, Emmeline C. Academia2, Shreya R. Shah1, John F. Morton5, Carly A. Holstein6, Dan B. Martin6, Matt Kaeberlein7, Warren C. Ladiges5, Pamela J. Fink4, Vivian L. MacKay1, David L. Wiest3, Brian K. Kennedy1,2* 1 Department of Biochemistry, University of Washington, Seattle, Washington, United States of America, 2 Buck Institute for Research on Aging, Novato, California, United States of America, 3 Blood Cell Development and Cancer Keystone, Immune Cell Development and Host Defense Program, Fox Chase Cancer Center, Philadelphia, Pennsylvania, United States of America, 4 Department of Immunology, University of Washington, Seattle, Washington, United States of America, 5 Department of Comparative Medicine, University of Washington, Seattle, Washington, United States of America, 6 Institute for Systems Biology, Seattle, Washington, United States of America, 7 Department of Pathology, University of Washington, Seattle, Washington, United States of America Abstract Most yeast ribosomal protein genes are duplicated and their characterization has led to hypotheses regarding the existence of specialized ribosomes with different subunit composition or specifically-tailored functions. In yeast, ribosomal protein genes are generally duplicated and evidence has emerged that paralogs might have specific roles. Unlike yeast, most mammalian ribosomal proteins are thought to be encoded by a single gene copy, raising the possibility that heterogenous populations of ribosomes are unique to yeast. Here, we examine the roles of the mammalian Rpl22, finding that Rpl222/2 mice have only subtle phenotypes with no significant translation defects.
    [Show full text]
  • Assessment of Hematopoietic Failure Due to Rpl11 Deficiency in a Zebrafish Model of Diamond-Blackfan Anemia by Deep Sequencing
    Zhang et al. BMC Genomics 2013, 14:896 http://www.biomedcentral.com/1471-2164/14/896 RESEARCH ARTICLE Open Access Assessment of hematopoietic failure due to Rpl11 deficiency in a zebrafish model of Diamond- Blackfan anemia by deep sequencing Zhaojun Zhang1†, Haibo Jia2†, Qian Zhang1, Yang Wan3, Yang Zhou2, Qiong Jia2, Wanguang Zhang4, Weiping Yuan3, Tao Cheng3, Xiaofan Zhu3* and Xiangdong Fang1* Abstract Background: Diamond–Blackfan anemia is a rare congenital red blood cell dysplasia that develops soon after birth. RPL11 mutations account for approximately 4.8% of human DBA cases with defective hematopoietic phenotypes. However, the mechanisms by which RPL11 regulates hematopoiesis in DBA remain elusive. In this study, we analyzed the transcriptome using deep sequencing data from an Rpl11-deficient zebrafish model to identify Rpl11-mediated hematopoietic failure and investigate the underlying mechanisms. Results: We characterized hematological defects in Rpl11-deficient zebrafish embryos by identifying affected hematological genes, hematopoiesis-associated pathways, and regulatory networks. We found that hemoglobin biosynthetic and hematological defects in Rpl11-deficient zebrafish were related to dysregulation of iron metabolism-related genes, including tfa, tfr1b, alas2 and slc25a37, which are involved in heme and hemoglobin biosynthesis. In addition, we found reduced expression of the hematopoietic stem cells (HSC) marker cmyb and HSC transcription factors tal1 and hoxb4a in Rpl11-deficient zebrafish embryos, indicating that the hematopoietic defects may be related to impaired HSC formation, differentiation, and proliferation. However, Rpl11 deficiency did not affect the development of other blood cell lineages such as granulocytes and myelocytes. Conclusion: We identified hematopoietic failure of Rpl11-deficient zebrafish embryos using transcriptome deep sequencing and elucidated potential underlying mechanisms.
    [Show full text]
  • Overexpressed WDR3 Induces the Activation of Hippo Pathway by Interacting with GATA4 in Pancreatic Cancer
    Overexpressed WDR3 Induces the Activation of Hippo Pathway by Interacting with GATA4 in Pancreatic Cancer Wenjie Su Sichuan Provincial People's Hospital: Sichuan Academy of Medical Sciences and Sichuan People's Hospital Shikai Zhu Sichuan Provincial People's Hospital: Sichuan Academy of Medical Sciences and Sichuan People's Hospital Kai Chen Sichuan Provincial People's Hospital: Sichuan Academy of Medical Sciences and Sichuan People's Hospital Hongji Yang Sichuan Provincial People's Hospital: Sichuan Academy of Medical Sciences and Sichuan People's Hospital Mingwu Tian Sichuan Provincial People's Hospital: Sichuan Academy of Medical Sciences and Sichuan People's Hospital Qiang Fu Massachusetts General Hospital Ganggang Shi University of British Columbia School of Human Kinetics: The University of British Columbia School of Kinesiology Shijian Feng University of British Columbia School of Human Kinetics: The University of British Columbia School of Kinesiology Dianyun Ren Wuhan Union Hospital Xin Jin Wuhan Union Hospital Chong Yang ( [email protected] ) Sichuan Provincial People's Hospital: Sichuan Academy of Medical Sciences and Sichuan People's Hospital Page 1/34 Research Keywords: Pancreatic Cancer, WDR3, GATA4, YAP1, Hippo Signaling Pathway Posted Date: November 13th, 2020 DOI: https://doi.org/10.21203/rs.3.rs-104564/v1 License: This work is licensed under a Creative Commons Attribution 4.0 International License. Read Full License Version of Record: A version of this preprint was published on March 1st, 2021. See the published version at https://doi.org/10.1186/s13046-021-01879-w. Page 2/34 Abstract Background: WD repeat domain 3 (WDR3) is involved in a variety of cellular processes including gene regulation, cell cycle progression, signal transduction and apoptosis.
    [Show full text]
  • Identification of the Key Genes and Pathways in Prostate Cancer
    ONCOLOGY LETTERS 16: 6663-6669, 2018 Identification of the key genes and pathways in prostate cancer SHUTONG FAN1*, ZUMU LIANG1*, ZHIQIN GAO1, ZHIWEI PAN2, SHAOJIE HAN3, XIAOYING LIU1, CHUNLING ZHAO1, WEIWEI YANG1, ZHIFANG PAN1 and WEIGUO FENG1 1College of Bioscience and Technology, Weifang Medical University, Weifang, Shandong 261053; 2Department of Internal Medicine, Laizhou Development Zone Hospital, Yantai, Shandong 261400; 3Animal Epidemic Prevention and Epidemic Control Center, Changle County Bureau of Animal Health and Production, Weifang, Shandong 262400, P.R. China Received March 5, 2018; Accepted September 17, 2018 DOI: 10.3892/ol.2018.9491 Abstract. Prostate cancer (PCa) is one of the most common Introduction malignancies in men globally. The aim of the present study was to identify the key genes and pathways involved in the Prostate cancer (PCa) is one of the most common malignancies occurrence of PCa. Gene expression profile (GSE55945) in men globally and the second leading cause of cancer was downloaded from Gene Expression Omnibus, and associated mortality in developed countries (1,2). Like other the differentially expressed genes (DEGs) were identified. cancers, PCa is considered to be a disease which caused by Subsequently, Gene ontology analysis, KEGG pathway age, diet and gene aberrations (3). Accumulating evidences analysis and protein-protein interaction (PPI) analysis of have demonstrated that a series of genes and pathways involved DEGs were performed. Finally, the identified key genes were in the occurrence, progression and metastasis of PCa (4). At confirmed by immunohistochemistry. The GO analysis results present, the underlying mechanism of PCa occurrence is still showed that the DEGs were mainly participated in cell cycle, unclear, which limits the diagnosis and therapy.
    [Show full text]
  • Variation in Protein Coding Genes Identifies Information
    bioRxiv preprint doi: https://doi.org/10.1101/679456; this version posted June 21, 2019. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC-ND 4.0 International license. Animal complexity and information flow 1 1 2 3 4 5 Variation in protein coding genes identifies information flow as a contributor to 6 animal complexity 7 8 Jack Dean, Daniela Lopes Cardoso and Colin Sharpe* 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Institute of Biological and Biomedical Sciences 25 School of Biological Science 26 University of Portsmouth, 27 Portsmouth, UK 28 PO16 7YH 29 30 * Author for correspondence 31 [email protected] 32 33 Orcid numbers: 34 DLC: 0000-0003-2683-1745 35 CS: 0000-0002-5022-0840 36 37 38 39 40 41 42 43 44 45 46 47 48 49 Abstract bioRxiv preprint doi: https://doi.org/10.1101/679456; this version posted June 21, 2019. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC-ND 4.0 International license. Animal complexity and information flow 2 1 Across the metazoans there is a trend towards greater organismal complexity. How 2 complexity is generated, however, is uncertain. Since C.elegans and humans have 3 approximately the same number of genes, the explanation will depend on how genes are 4 used, rather than their absolute number.
    [Show full text]
  • Robustness and Timing of Cellular Differentiation Through Population-Based Symmetry Breaking
    AR TI CLE Robustness AND TIMING OF CELLULAR DIFFERENTIATION THROUGH population-based SYMMETRY BREAKING Angel StanoeV1 | Christian Schröter1 | Aneta KOSESKA1∗ 1Department OF Systemic Cell Biology, Max Planck Institute OF Molecular PhYSIOLOGY, Although COORDINATED BEHAVIOR OF MULTICELLULAR ORGANISMS Dortmund, GermanY RELIES ON INTERCELLULAR communication, THE DYNAMICAL mech- Correspondence ANISM THAT UNDERLIES SYMMETRY BREAKING IN HOMOGENEOUS Email: populations, THEREBY GIVING RISE TO HETEROGENEOUS CELL TYPES ∗[email protected] REMAINS UNCLEAR. In CONTRAST TO THE PREVALENT cell-intrinsic VIEW OF DIFFERENTIATION WHERE MULTISTABILITY ON THE SINGLE CELL LEVEL IS A NECESSARY pre-requisite, WE PROPOSE THAT het- EROGENEOUS CELLULAR IDENTITIES EMERGE AND ARE MAINTAINED COOPERATIVELY ON A POPULATION LEVel. Identifying A GENERIC SYMMETRY BREAKING mechanism, WE DEMONSTRATE THAT ROBUST PROPORTIONS BETWEEN DIFFERENTIATED CELL TYPES ARE INTRINSIC FEATURES OF THIS INHOMOGENEOUS STEADY STATE solution. Crit- ICAL ORGANIZATION IN THE VICINITY OF THE SYMMETRY BREAKING BIFURCATION ON THE OTHER hand, SUGGESTS THAT TIMING OF cel- LULAR DIFFERENTIATION EMERGES FOR GROWING POPULATIONS IN A self-organized MANNER. Setting A CLEAR DISTINCTION BETWEEN pre-eXISTING ASYMMETRIES AND SYMMETRY BREAKING EVents, WE THUS DEMONSTRATE THAT EMERGENT SYMMETRY breaking, IN CONJUNCTION WITH ORGANIZATION NEAR CRITICALITY NECESSARILY LEADS TO ROBUSTNESS AND ACCURACY DURING DEVelopment. KEYWORDS SYMMETRY breaking; differentiation; INHOMOGENEOUS STEADY STATE Abbreviations:
    [Show full text]
  • Download Report 2010-12
    RESEARCH REPORt 2010—2012 MAX-PLANCK-INSTITUT FÜR WISSENSCHAFTSGESCHICHTE Max Planck Institute for the History of Science Cover: Aurora borealis paintings by William Crowder, National Geographic (1947). The International Geophysical Year (1957–8) transformed research on the aurora, one of nature’s most elusive and intensely beautiful phenomena. Aurorae became the center of interest for the big science of powerful rockets, complex satellites and large group efforts to understand the magnetic and charged particle environment of the earth. The auroral visoplot displayed here provided guidance for recording observations in a standardized form, translating the sublime aesthetics of pictorial depictions of aurorae into the mechanical aesthetics of numbers and symbols. Most of the portait photographs were taken by Skúli Sigurdsson RESEARCH REPORT 2010—2012 MAX-PLANCK-INSTITUT FÜR WISSENSCHAFTSGESCHICHTE Max Planck Institute for the History of Science Introduction The Max Planck Institute for the History of Science (MPIWG) is made up of three Departments, each administered by a Director, and several Independent Research Groups, each led for five years by an outstanding junior scholar. Since its foundation in 1994 the MPIWG has investigated fundamental questions of the history of knowl- edge from the Neolithic to the present. The focus has been on the history of the natu- ral sciences, but recent projects have also integrated the history of technology and the history of the human sciences into a more panoramic view of the history of knowl- edge. Of central interest is the emergence of basic categories of scientific thinking and practice as well as their transformation over time: examples include experiment, ob- servation, normalcy, space, evidence, biodiversity or force.
    [Show full text]
  • Arxiv:1910.00443V3 [Eess.IV] 29 Jul 2020 Synchronize Acquired Data Sets, Such That Corresponding Developmental Stages Are Compared to One Another [3, 6]
    Towards Automatic Embryo Staging in 3D+t Microscopy Images using Convolutional Neural Networks and PointNets? Manuel Traub1;2[0000−0003−0897−1701] and Johannes Stegmaier1[0000−0003−4072−3759] 1 Institute of Imaging and Computer Vision, RWTH Aachen University, Germany 2 Institute for Automation and Applied Informatics, Karlsruhe Institute of Technology, Germany [email protected] Abstract. Automatic analyses and comparisons of different stages of embryonic development largely depend on a highly accurate spatiotem- poral alignment of the investigated data sets. In this contribution, we assess multiple approaches for automatic staging of developing embryos that were imaged with time-resolved 3D light-sheet microscopy. The methods comprise image-based convolutional neural networks as well as an approach based on the PointNet architecture that directly operates on 3D point clouds of detected cell nuclei centroids. The experiments with four wild-type zebrafish embryos render both approaches suitable for au- tomatic staging with average deviations of 21 − 34 minutes. Moreover, a proof-of-concept evaluation based on simulated 3D+t point cloud data sets shows that average deviations of less than 7 minutes are possible. Keywords: Convolutional Neural Networks · PointNet · Regression · Transfer Learning · Developmental Biology · Simulating Embryogenesis. 1 Introduction Embryonic development is characterized by a multitude of synchronized events, cell shape changes and large-scale tissue rearrangements that are crucial steps in the successful formation of a new organism [10]. To be able to compare these developmental events among different wild-type individuals, different mutants or upon exposure to certain chemicals, it is highly important to temporally arXiv:1910.00443v3 [eess.IV] 29 Jul 2020 synchronize acquired data sets, such that corresponding developmental stages are compared to one another [3, 6].
    [Show full text]
  • Deep Multiomics Profiling of Brain Tumors Identifies Signaling Networks
    ARTICLE https://doi.org/10.1038/s41467-019-11661-4 OPEN Deep multiomics profiling of brain tumors identifies signaling networks downstream of cancer driver genes Hong Wang 1,2,3, Alexander K. Diaz3,4, Timothy I. Shaw2,5, Yuxin Li1,2,4, Mingming Niu1,4, Ji-Hoon Cho2, Barbara S. Paugh4, Yang Zhang6, Jeffrey Sifford1,4, Bing Bai1,4,10, Zhiping Wu1,4, Haiyan Tan2, Suiping Zhou2, Laura D. Hover4, Heather S. Tillman 7, Abbas Shirinifard8, Suresh Thiagarajan9, Andras Sablauer 8, Vishwajeeth Pagala2, Anthony A. High2, Xusheng Wang 2, Chunliang Li 6, Suzanne J. Baker4 & Junmin Peng 1,2,4 1234567890():,; High throughput omics approaches provide an unprecedented opportunity for dissecting molecular mechanisms in cancer biology. Here we present deep profiling of whole proteome, phosphoproteome and transcriptome in two high-grade glioma (HGG) mouse models driven by mutated RTK oncogenes, PDGFRA and NTRK1, analyzing 13,860 proteins and 30,431 phosphosites by mass spectrometry. Systems biology approaches identify numerous master regulators, including 41 kinases and 23 transcription factors. Pathway activity computation and mouse survival indicate the NTRK1 mutation induces a higher activation of AKT down- stream targets including MYC and JUN, drives a positive feedback loop to up-regulate multiple other RTKs, and confers higher oncogenic potency than the PDGFRA mutation. A mini-gRNA library CRISPR-Cas9 validation screening shows 56% of tested master regulators are important for the viability of NTRK-driven HGG cells, including TFs (Myc and Jun) and metabolic kinases (AMPKa1 and AMPKa2), confirming the validity of the multiomics inte- grative approaches, and providing novel tumor vulnerabilities.
    [Show full text]