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Cell-Cell Interactions
7 Cell-Cell Interactions Concept Outline 7.1 Cells signal one another with chemicals. Receptor Proteins and Signaling between Cells. Receptor proteins embedded in the plasma membrane change shape when they bind specific signal molecules, triggering a chain of events within the cell. Types of Cell Signaling. Cell signaling can occur between adjacent cells, although chemical signals called hormones act over long distances. 7.2 Proteins in the cell and on its surface receive signals from other cells. Intracellular Receptors. Some receptors are located within the cell cytoplasm. These receptors respond to lipid- soluble signals, such as steroid hormones. Cell Surface Receptors. Many cell-to-cell signals are water-soluble and cannot penetrate membranes. Instead, the signals are received by transmembrane proteins protruding out from the cell surface. 7.3 Follow the journey of information into the cell. FIGURE 7.1 Persimmon cells in close contact with one another. These Initiating the Intracellular Signal. Cell surface receptors plant cells and all cells, no matter what their function, interact often use “second messengers” to transmit a signal to the with their environment, including the cells around them. cytoplasm. Amplifying the Signal: Protein Kinase Cascades. Surface receptors and second messengers amplify signals as id you know that each of the 100 trillion cells of your they travel into the cell, often toward the cell nucleus. Dbody shares one key feature with the cells of tigers, bumblebees, and persimmons (figure 7.1)—a feature that 7.4 Cell surface proteins mediate cell-cell interactions. most bacteria and protists lack? Your cells touch and com- The Expression of Cell Identity. -
Vocabulario De Morfoloxía, Anatomía E Citoloxía Veterinaria
Vocabulario de Morfoloxía, anatomía e citoloxía veterinaria (galego-español-inglés) Servizo de Normalización Lingüística Universidade de Santiago de Compostela COLECCIÓN VOCABULARIOS TEMÁTICOS N.º 4 SERVIZO DE NORMALIZACIÓN LINGÜÍSTICA Vocabulario de Morfoloxía, anatomía e citoloxía veterinaria (galego-español-inglés) 2008 UNIVERSIDADE DE SANTIAGO DE COMPOSTELA VOCABULARIO de morfoloxía, anatomía e citoloxía veterinaria : (galego-español- inglés) / coordinador Xusto A. Rodríguez Río, Servizo de Normalización Lingüística ; autores Matilde Lombardero Fernández ... [et al.]. – Santiago de Compostela : Universidade de Santiago de Compostela, Servizo de Publicacións e Intercambio Científico, 2008. – 369 p. ; 21 cm. – (Vocabularios temáticos ; 4). - D.L. C 2458-2008. – ISBN 978-84-9887-018-3 1.Medicina �������������������������������������������������������������������������veterinaria-Diccionarios�������������������������������������������������. 2.Galego (Lingua)-Glosarios, vocabularios, etc. políglotas. I.Lombardero Fernández, Matilde. II.Rodríguez Rio, Xusto A. coord. III. Universidade de Santiago de Compostela. Servizo de Normalización Lingüística, coord. IV.Universidade de Santiago de Compostela. Servizo de Publicacións e Intercambio Científico, ed. V.Serie. 591.4(038)=699=60=20 Coordinador Xusto A. Rodríguez Río (Área de Terminoloxía. Servizo de Normalización Lingüística. Universidade de Santiago de Compostela) Autoras/res Matilde Lombardero Fernández (doutora en Veterinaria e profesora do Departamento de Anatomía e Produción Animal. -
Cooperative Coupling of Cell-Matrix and Cell–Cell Adhesions in Cardiac Muscle
Cooperative coupling of cell-matrix and cell–cell adhesions in cardiac muscle Megan L. McCaina, Hyungsuk Leea,1, Yvonne Aratyn-Schausa, André G. Kléberb, and Kevin Kit Parkera,2 aDisease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138; and bDepartment of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215 Edited by Robert Langer, Massachusetts Institute of Technology, Cambridge, MA, and approved May 1, 2012 (received for review February 21, 2012) Adhesion between cardiac myocytes is essential for the heart to serve as cues for remodeling adhesions and assembling tissues. In function as an electromechanical syncytium. Although cell-matrix vitro studies have demonstrated that cytoskeletal tension (27) and and cell–cell adhesions reorganize during development and dis- exogenous cyclic strain (28, 29) promote cell–cell adhesion and ease, the hierarchical cooperation between these subcellular struc- tissue assembly in many cell types. Culturing noncardiac cells tures is poorly understood. We reasoned that, during cardiac on stiff substrates tips the balance of adhesion in favor of focal development, focal adhesions mechanically stabilize cells and tis- adhesions and away from cell–cell adhesions (30–32), suggesting sues during myofibrillogenesis and intercalated disc assembly. As that mechanical forces can modulate the assembly or disassembly the intercalated disc matures, we postulated that focal -
Differences in Neural Stem Cell Identity and Differentiation Capacity Drive Divergent Regenerative Outcomes in Lizards and Salamanders
Differences in neural stem cell identity and differentiation capacity drive divergent regenerative outcomes in lizards and salamanders Aaron X. Suna,b,c, Ricardo Londonoa, Megan L. Hudnalla, Rocky S. Tuana,c, and Thomas P. Lozitoa,1 aCenter for Cellular and Molecular Engineering, Department of Orthopaedic Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA 15219; bMedical Scientist Training Program, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213; and cDepartment of Bioengineering, University of Pittsburgh Swanson School of Engineering, Pittsburgh, PA 15213 Edited by Robb Krumlauf, Stowers Institute for Medical Research, Kansas City, MO, and approved July 24, 2018 (received for review March 2, 2018) While lizards and salamanders both exhibit the ability to re- lizard tail regenerate (20), and the key to understanding this generate amputated tails, the outcomes achieved by each are unique arrangement of tissues is in identifying the patterning markedly different. Salamanders, such as Ambystoma mexicanum, signals involved. regenerate nearly identical copies of original tails. Regenerated lizard Both lizards and salamanders follow similar mechanisms of tails, however, exhibit important morphological differences compared tail development during embryonic development. The embryonic with originals. Some of these differences concern dorsoventral pat- spinal cord and surrounding structures are formed and patterned terning of regenerated skeletal and spinal cord tissues; regenerated by the neural tube (21, 22). The neural tube exhibits distinct + salamander tail tissues exhibit dorsoventral patterning, while re- domains: roof plate (characterized by expression of Pax7 , BMP- + + + grown lizard tissues do not. Additionally, regenerated lizard tails lack 2 , and Sox10 among others), lateral domain (Pax6 ), and floor + + characteristically roof plate-associated structures, such as dorsal root plate (Shh , FoxA2 ). -
Reaction of Ependymal Cells to Spinal Cord Injury: a Potential Role for Oncostatin Pathway and Microglial Cells
bioRxiv preprint doi: https://doi.org/10.1101/2021.02.12.428106; this version posted February 13, 2021. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. Reaction of ependymal cells to spinal cord injury: a potential role for oncostatin pathway and microglial cells *1 *1 *1 2 2 1 R. Chevreau , H Ghazale , C Ripoll , C Chalfouh , Q Delarue , A.L. Hemonnot , H 1 3 4 5 *2 *1 Hirbec , S Wahane , F Perrin , H Noristani , N Guerout , JP Hugnot *equal contribution, listed in alphabetic order 1 Université de Montpellier, INSERM CNRS IGF, France 2 Université de Rouen, France 3 Departments of Neurobiology and Neurosurgery, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles CA 90095-1763, USA. 4 University of Montpellier, INSERM MMDN France 5 Shriners Hospitals Pediatric Research Center, NY, USA Abstract Ependymal cells with stem cell properties reside in the adult spinal cord around the central canal. They rapidly activate and proliferate after spinal cord injury, constituting a source of new cells. They produce neurons and glial cells in lower vertebrates but they mainly generate glial cells in mammals. The mechanisms underlying their activation and their glial-biased differentiation in mammals remain ill-defined. This represents an obstacle to control these cells. We addressed this issue using RNA profiling of ependymal cells before and after injury. We found that these cells activate STAT3 and ERK/MAPK signaling during injury and downregulate cilia-associated genes and FOXJ1, a central transcription factor in ciliogenesis. -
Cx43 and the Actin Cytoskeleton: Novel Roles and Implications for Cell-Cell Junction-Based Barrier Function Regulation
biomolecules Review Cx43 and the Actin Cytoskeleton: Novel Roles and Implications for Cell-Cell Junction-Based Barrier Function Regulation Randy E. Strauss 1,* and Robert G. Gourdie 2,3,4,* 1 Virginia Tech, Translational Biology Medicine and Health (TBMH) Program, Roanoke, VA 24016, USA 2 Center for Heart and Reparative Medicine Research, Fralin Biomedical Research Institute at Virginia Tech Carilion, Roanoke, VA 24016, USA 3 Virginia Tech Carilion School of Medicine, Roanoke, VA 24016, USA 4 Department of Biomedical Engineering and Mechanics, Virginia Polytechnic Institute and State University, Blacksburg, VA 24060, USA * Correspondence: [email protected] (R.E.S.); [email protected] (R.G.G.) Received: 29 October 2020; Accepted: 7 December 2020; Published: 10 December 2020 Abstract: Barrier function is a vital homeostatic mechanism employed by epithelial and endothelial tissue. Diseases across a wide range of tissue types involve dynamic changes in transcellular junctional complexes and the actin cytoskeleton in the regulation of substance exchange across tissue compartments. In this review, we focus on the contribution of the gap junction protein, Cx43, to the biophysical and biochemical regulation of barrier function. First, we introduce the structure and canonical channel-dependent functions of Cx43. Second, we define barrier function and examine the key molecular structures fundamental to its regulation. Third, we survey the literature on the channel-dependent roles of connexins in barrier function, with an emphasis on the role of Cx43 and the actin cytoskeleton. Lastly, we discuss findings on the channel-independent roles of Cx43 in its associations with the actin cytoskeleton and focal adhesion structures highlighted by PI3K signaling, in the potential modulation of cellular barriers. -
Wnt/Β-Catenin Signaling Regulates Ependymal Cell Development and Adult Homeostasis
Wnt/β-catenin signaling regulates ependymal cell development and adult homeostasis Liujing Xinga, Teni Anbarchiana, Jonathan M. Tsaia, Giles W. Plantb, and Roeland Nussea,c,1 aDepartment of Developmental Biology, Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA 94305; bDepartment of Neurosurgery, Stanford University School of Medicine, Stanford, CA 94305; and cHoward Hughes Medical Institute, Stanford, CA 94305 Contributed by Roeland Nusse, May 22, 2018 (sent for review February 23, 2018; reviewed by Bin Chen and Samuel Pleasure) In the adult mouse spinal cord, the ependymal cell population that precursors and are present before the onset of neurogenesis. surrounds the central canal is thought to be a promising source of They give rise to radial glial cells, which then become the pre- quiescent stem cells to treat spinal cord injury. Relatively little is dominant progenitors during gliogenesis (19, 20). Eventually, known about the cellular origin of ependymal cells during spinal ependymal cells are formed as the ventricle and the ventricular cord development, or the molecular mechanisms that regulate zone retract through the process of obliteration. This process is ependymal cells during adult homeostasis. Using genetic lineage accompanied by terminal differentiation and exit of radial glial tracing based on the Wnt target gene Axin2, we have character- cells from the ventricular zone (18, 19, 21–24). ized Wnt-responsive cells during spinal cord development. Our Compared with our knowledge about ependymal cells in the results revealed that Wnt-responsive progenitor cells are restricted brain, little is known about the cellular origin of spinal cord to the dorsal midline throughout spinal cord development, which ependymal cells. -
The Fine Structure of Ependyma in the Brain Of
THE FINE STRUCTURE OF EPENDYMA IN THE BRAIN OF THE RAT M. W. BRIGHTMAN, Ph.D., and S. L. PALAY, M.D. From the Laboratory of Neuroanatomical Sciences, National Institute of Neurological Diseases and Blindness, National Institutes of Health, Bethesda, Maryland. Dr. Palay's present address is Department of Anatomy, Harvard Medical School, Boston ABSTRACT The ciliated ependyma of the rat brain consists of a sheet of epithelial cells, the luminal surface of which is reflected over ciliary shafts and numerous evaginations of irregular di- mensions. The relatively straight lateral portions of the plasmalemma of contiguous cells are fused at discrete sites to form five-layered junctions or zonulae occludentes which obliterate the intercellular space. These fusions occur usually at some distance below the free surface either independently or in continuity with a second intercellular junction, the zonula adhaerens. The luminal junction is usually formed by a zonula adhaerens or, occasionally, by a zonula occludens. The finely granular and filamentous cytoplasm contains supranuclear dense bodies, some of which are probably lysosomes and dense whorls of perinuclear filaments which send fascicles toward the lateral plasmalemma. The apical regions of the cytoplasm contain the basal body complexes of neighboring cilia. These complexes include a striated basal foot and short, non-striated rootlets emanating from the wall of each basal body. The rootlets end in a zone of granules about the proximal region of the basal body, adjacent to which may lie a striated mass of variable shape. All components of the basal body complex of adjacent cilia are independent of each other. -
Transcriptional Control of Hypothalamic Tanycyte
TRANSCRIPTIONAL CONTROL OF HYPOTHALAMIC TANYCYTE DEVELOPMENT By Ana Lucia Miranda-Angulo A dissertation submitted to the Johns Hopkins University in conformity with the requirements for the degree of Doctor of Philosophy Baltimore, Maryland March 2013 © 2013 Ana Lucia Miranda-Angulo All Rights Reserved Abstract The wall of the ventral third ventricle is composed of two distinct cell populations; tanycytes and ependymal cells. Tanycytes support several hypothalamic functions but little is known about the transcriptional network which regulates their development. We explored the developmental expression of multiple transcription factors by in situ hybridization and found that the retina and anterior neural fold homeobox transcription factor (Rax) was expressed in both ventricular progenitors of the hypothalamic primordium and differentiating tanycytes. Rax is known to participate in retina and hypothalamus development but nothing is known about its function in tanycytes. To explore the role of Rax in hypothalamic tanycyte development we generated Rax haploinsufficient mice. These mice appeared grossly normal, but careful examination revealed a thinning of the third ventricular wall and reduction of tanycyte and ependymal markers. These experiments show that Rax is required for tanycyte and ependymal cell progenitor proliferation and/or survival. Rax haploinsufficiency also resulted in ectopic presence of ependymal cells in the α2 tanycytic zone were few ependymal cells are normally found. Thus, the presence of ependymal cell in this zone suggests that Rax was required for α2 tanycyte differentiation. These changes in the ventricular wall were associated with reduced diffusion of Evans Blue tracer from the ventricle to the hypothalamic parenchyma. Furthermore, we have provided in vivo and in vitro evidence suggesting that RAX protein is secreted by tanycytes, and subsequently internalized by adjacent and distal cells. -
Índice De Denominacións Españolas
VOCABULARIO Índice de denominacións españolas 255 VOCABULARIO 256 VOCABULARIO agente tensioactivo pulmonar, 2441 A agranulocito, 32 abaxial, 3 agujero aórtico, 1317 abertura pupilar, 6 agujero de la vena cava, 1178 abierto de atrás, 4 agujero dental inferior, 1179 abierto de delante, 5 agujero magno, 1182 ablación, 1717 agujero mandibular, 1179 abomaso, 7 agujero mentoniano, 1180 acetábulo, 10 agujero obturado, 1181 ácido biliar, 11 agujero occipital, 1182 ácido desoxirribonucleico, 12 agujero oval, 1183 ácido desoxirribonucleico agujero sacro, 1184 nucleosómico, 28 agujero vertebral, 1185 ácido nucleico, 13 aire, 1560 ácido ribonucleico, 14 ala, 1 ácido ribonucleico mensajero, 167 ala de la nariz, 2 ácido ribonucleico ribosómico, 168 alantoamnios, 33 acino hepático, 15 alantoides, 34 acorne, 16 albardado, 35 acostarse, 850 albugínea, 2574 acromático, 17 aldosterona, 36 acromatina, 18 almohadilla, 38 acromion, 19 almohadilla carpiana, 39 acrosoma, 20 almohadilla córnea, 40 ACTH, 1335 almohadilla dental, 41 actina, 21 almohadilla dentaria, 41 actina F, 22 almohadilla digital, 42 actina G, 23 almohadilla metacarpiana, 43 actitud, 24 almohadilla metatarsiana, 44 acueducto cerebral, 25 almohadilla tarsiana, 45 acueducto de Silvio, 25 alocórtex, 46 acueducto mesencefálico, 25 alto de cola, 2260 adamantoblasto, 59 altura a la punta de la espalda, 56 adenohipófisis, 26 altura anterior de la espalda, 56 ADH, 1336 altura del esternón, 47 adipocito, 27 altura del pecho, 48 ADN, 12 altura del tórax, 48 ADN nucleosómico, 28 alunarado, 49 ADNn, 28 -
Defining the Roles of B-Catenin and Plakoglobin in Cell-Cell
CELL STRUCTURE AND FUNCTION 30: 25–34 (2005) © 2005 by Japan Society for Cell Biology Defining the Roles of -catenin and Plakoglobin in Cell-cell Adhesion: Isolation of -catenin/plakoglobin-deficient F9 Cells Yoshitaka Fukunaga1,2, Huijie Liu1, Masayuki Shimizu1, Satoshi Komiya1, Michio Kawasuji2 and Akira Nagafuchi1 1Division of Cellular Interactions, Institute of Molecular Embryology and Genetics, Kumamoto University, Honjo 2-2-1, Kumamoto 860-0811 and 2Department of Surgery I, Graduate School of Medical Sciences, Kumamoto University, Honjo 1-1-1, Kumamoto 860-8556, Japan ABSTRACT. F9 teratocarcinoma cells in which -catenin and/or plakoglobin genes are knocked-out were generated and investigated in an effort to define the role of -catenin and plakoglobin in cell adhesion. Loss of -catenin expression only did not affect cadherin-mediated cell adhesion activity. Loss of both -catenin and plakoglobin expression, however, severely affected the strong cell adhesion activity of cadherin. In -catenin- deficient cells, the amount of plakoglobin associated with E-cadherin dramatically increased. In -catenin/ plakoglobin-deficient cells, the level of E-cadherin and -catenin markedly decreased. In these cells, E-cadherin formed large aggregates in cytoplasm and membrane localization of -catenin was barely detected. These data confirmed that -catenin or plakoglobin is required for -catenin to form complex with E-cadherin. It was also demonstrated that plakoglobin can compensate for the absence of -catenin. Moreover it was suggested that -catenin or plakoglobin is required not only for the cell adhesion activity but also for the stable expression and cell surface localization of E-cadherin. Key words: F9/-catenin/plakoglobin/targeting/cadherin/cell adhesion Introduction to as desmosomes. -
Restoration of Desmosomal Junction Protein Expression and Inhibition Of
MOLECULAR AND CLINICAL ONCOLOGY 3: 171-178, 2015 Restoration of desmosomal junction protein expression and inhibition of H3K9‑specifichistone demethylase activity by cytostatic proline‑rich polypeptide‑1 leads to suppression of tumorigenic potential in human chondrosarcoma cells KARINA GALOIAN1, AMIR QURESHI1, GINA WIDEROFF1 and H.T. TEMPLE2 1Department of Orthopaedic Surgery; 2University of Miami Tissue Bank Division, Miller School of Medicine, University of Miami, Miami, FL 33136, USA Received September 18, 2014; Accepted October 8, 2014 DOI: 10.3892/mco.2014.445 Abstract. Disruption of cell-cell junctions and the concomi- and inhibits H3K9 demethylase activity, contributing to the tant loss of polarity, downregulation of tumor-suppressive suppression of tumorigenic potential in chondrosarcoma cells. adherens junctions and desmosomes represent hallmark phenotypes for several different cancer cells. Moreover, a Introduction variety of evidence supports the argument that these two common phenotypes of cancer cells directly contribute to Chondrosarcoma is a highly aggressive bone cancer of tumorigenesis. In this study, we aimed to determine the status mesenchymal origin, which is resistant to chemo- and radia- of intercellular junction proteins expression in JJ012 human tion therapies, leaving surgical resection as the only option. malignant chondrosarcoma cells and investigate the effect Metastatic spread of malignant cells eventually develops of the antitumorigenic cytokine, proline-rich polypeptide-1 following surgical resection. The malignant progression to (PRP-1) on their expression. The cell junction pathway array chondrosarcoma has been suggested to involve a degree of data indicated downregulation of desmosomal proteins, mesenchymal-to-epithelial transition (MET) and it has been such as desmoglein (1,428-fold), desmoplakin (620-fold) and demonstrated in an in vitro model that chondrosarcoma cells plakoglobin (442-fold).