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Conservation and Diversification of Appendage Identity Specification Mechanisms Along the Anteroposterior and Proximodistal Axes in Panarthropoda Frank W
University of Connecticut OpenCommons@UConn Doctoral Dissertations University of Connecticut Graduate School 8-23-2013 Conservation and Diversification of Appendage Identity Specification Mechanisms Along the Anteroposterior and Proximodistal Axes in Panarthropoda Frank W. Smith III University of Connecticut, [email protected] Follow this and additional works at: https://opencommons.uconn.edu/dissertations Recommended Citation Smith, Frank W. III, "Conservation and Diversification of Appendage Identity Specification Mechanisms Along the Anteroposterior and Proximodistal Axes in Panarthropoda" (2013). Doctoral Dissertations. 161. https://opencommons.uconn.edu/dissertations/161 Conservation and Diversification of Appendage Identity Specification Mechanisms Along the Anteroposterior and Proximodistal Axes in Panarthropoda Frank Wesley Smith III, PhD University of Connecticut, 2013 A key characteristic of arthropods is their diverse serially homologous segmented appendages. This dissertation explores diversification of these appendages, and the developmental mechanisms producing them. In Chapter 1, the roles of genes that specify antennal identity in Drosophila melanogaster were investigated in the flour beetle Tribolium castaneum. Antenna-to-leg transformations occurred in response to RNA interference (RNAi) against homothorax, extradenticle, spineless and Distal-less. However, for homothorax/extradenticle RNAi, the extent of transformation along the proximodistal axis differed between embryogenesis and metamorphosis. This suggests that distinct mechanisms specify antennal identity during flour beetle embryogenesis and metamorphosis and leads to a model for the evolution of the Drosophila antennal identity mechanism. Homothorax/Extradenticle acquire many of their identity specification roles by acting as Hox cofactors. In chapter 2, the metamorphic roles of the Hox genes, extradenticle, and homothorax were compared in T. castaneum. homothorax/extradenticle RNAi and Hox RNAi produced similar body wall phenotypes but different appendage phenotypes. -
Subject Index
979 Subject Index Acellularity Asymmetry of embryonic starfish mesenchyme cells: KANEKO AND development of left/right asymmetry: BROWN AND OTHERS 129 WOLPERT 1 Acetylcholinesterase Avian tropomyosin/cholinesterase expression in ascidian embryo zygotes: CROWTHER AND OTHERS 953 localization of bFGF: KALCHEIM AND NEUFELD 203 Acrosome Axis reaction anterior-posterior zona receptors on guinea-pig spermatozoa: JONES AND organizer amount and axial pattern in Xenopus: WILLIAMS 41 STEWART AND GERHART 363 Actin Axogenesis effect of stretch on muscle gene expression: LOUGHNA AND Thy-1 expression in murine olfactory bulb: XUE AND OTHERS 217 OTHERS 851 Adult Axolotl rat embryo perinatnl ndu coexistence of O-2A and O-2A " progenitors: extracellular matrix in neural crest pathways: PERRIS WOLSWIJK AND OTHERS 691 AND OTHERS 533 Aggregation Axon pattern guidance of Dictyostelium discoideum: FOERSTER AND OTHERS 11 axon patterning at rat floor plate: BOVOLENTA AND Aging DODD 435 NGF receptor in rat dental tissue: BYERS AND OTHERS 461 outgrowth Agouti growth associated protein in chick visual system: cellular action of the mouse lethal yellow mutation: BARSH SCHLOSSHAUER AND OTHERS 395 AND OTHERS 683 rat Ammonia prenatal Schwann cell development: MIRSKY AND promotes cAMP accumulation in Dictyostelium: RILEY AND OTHERS 105 BARCLAY 715 regeneration AMP effects of protease inhibitors: FAWCETT AND HOUSDEN cyclic 59 ammonia promotes cAMP accumulation in Dictyostelium: RILEY AND BARCLAY 715 prenatal Schwann cell development: MIRSKY AND Back-transplantation OTHERS -
Clonal Dispersion During Neural Tube Formation 4097 of Neuromeres
Development 126, 4095-4106 (1999) 4095 Printed in Great Britain © The Company of Biologists Limited 1999 DEV2458 Successive patterns of clonal cell dispersion in relation to neuromeric subdivision in the mouse neuroepithelium Luc Mathis1,*, Johan Sieur1, Octavian Voiculescu2, Patrick Charnay2 and Jean-François Nicolas1,‡ 1Unité de Biologie moléculaire du Développement, Institut Pasteur, 25, rue du Docteur Roux, 75724 Paris Cedex 15, France 2Unité INSERM 368, Ecole Normale Supérieure, 46 rue d’Ulm, 75230 Paris Cedex 05, France *Present address: Beckman Institute (139-74), California Institute of Technology, Pasadena, CA, 91125, USA ‡Author for correspondence (e-mail: [email protected]) Accepted 5 July; published on WWW 23 August 1999 SUMMARY We made use of the laacz procedure of single-cell labelling the AP and DV axis of the neural tube. A similar sequence to visualize clones labelled before neuromere formation, in of AP cell dispersion followed by an arrest of AP cell 12.5-day mouse embryos. This allowed us to deduce two dispersion, a preferential DV cell dispersion and then by a successive phases of cell dispersion in the formation of the coherent neuroepithelial growth, is also observed in the rhombencephalon: an initial anterior-posterior (AP) cell spinal cord and mesencephalon. This demonstrates that a dispersion, followed by an asymmetrical dorsoventral (DV) similar cascade of cell events occurs in these different cell distribution during which AP cell dispersion occurs in domains of the CNS. In the prosencephalon, differences in territories smaller than one rhombomere. We conclude that spatial constraints may explain the variability in the the general arrest of AP cell dispersion precedes the onset orientation of cell clusters. -
Stages of Embryonic Development of the Zebrafish
DEVELOPMENTAL DYNAMICS 2032553’10 (1995) Stages of Embryonic Development of the Zebrafish CHARLES B. KIMMEL, WILLIAM W. BALLARD, SETH R. KIMMEL, BONNIE ULLMANN, AND THOMAS F. SCHILLING Institute of Neuroscience, University of Oregon, Eugene, Oregon 97403-1254 (C.B.K., S.R.K., B.U., T.F.S.); Department of Biology, Dartmouth College, Hanover, NH 03755 (W.W.B.) ABSTRACT We describe a series of stages for Segmentation Period (10-24 h) 274 development of the embryo of the zebrafish, Danio (Brachydanio) rerio. We define seven broad peri- Pharyngula Period (24-48 h) 285 ods of embryogenesis-the zygote, cleavage, blas- Hatching Period (48-72 h) 298 tula, gastrula, segmentation, pharyngula, and hatching periods. These divisions highlight the Early Larval Period 303 changing spectrum of major developmental pro- Acknowledgments 303 cesses that occur during the first 3 days after fer- tilization, and we review some of what is known Glossary 303 about morphogenesis and other significant events that occur during each of the periods. Stages sub- References 309 divide the periods. Stages are named, not num- INTRODUCTION bered as in most other series, providing for flexi- A staging series is a tool that provides accuracy in bility and continued evolution of the staging series developmental studies. This is because different em- as we learn more about development in this spe- bryos, even together within a single clutch, develop at cies. The stages, and their names, are based on slightly different rates. We have seen asynchrony ap- morphological features, generally readily identi- pearing in the development of zebrafish, Danio fied by examination of the live embryo with the (Brachydanio) rerio, embryos fertilized simultaneously dissecting stereomicroscope. -
Metamerism in Cephalochordates and the Problem of the Vertebrate Head TAKAYUKI ONAI*,1,2, NORITAKA ADACHI1 and SHIGERU KURATANI1
Int. J. Dev. Biol. 61: 621-632 (2017) doi: 10.1387/ijdb.170121to www.intjdevbiol.com Metamerism in cephalochordates and the problem of the vertebrate head TAKAYUKI ONAI*,1,2, NORITAKA ADACHI1 and SHIGERU KURATANI1 1Evolutionary Morphology Laboratory, RIKEN center for Developmental Biology, Chuo-ku, Kobe, Japan and 2Department of Anatomy, School of Medical Sciences, University of Fukui, Matsuokashimoaizuki, Japan ABSTRACT The vertebrate head characteristically exhibits a complex pattern with sense organs, brain, paired eyes and jaw muscles, and the brain case is not found in other chordates. How the extant vertebrate head has evolved remains enigmatic. Historically, there have been two conflicting views on the origin of the vertebrate head, segmental and non-segmental views. According to the segmentalists, the vertebrate head is organized as a metameric structure composed of segments equivalent to those in the trunk; a metamere in the vertebrate head was assumed to consist of a somite, a branchial arch and a set of cranial nerves, considering that the head evolved from rostral segments of amphioxus-like ancestral vertebrates. Non-segmentalists, however, considered that the vertebrate head was not segmental. In that case, the ancestral state of the vertebrate head may be non-segmented, and rostral segments in amphioxus might have been secondarily gained, or extant vertebrates might have evolved through radical modifications of amphioxus-like ancestral vertebrate head. Comparative studies of mesodermal development in amphioxus and vertebrate gastrula embryos have revealed that mesodermal gene expressions become segregated into two domains anteroposteriorly to specify the head mesoderm and trunk mesoderm only in vertebrates; in this segregation, key genes such as delta and hairy, involved in segment formation, are expressed in the trunk mesoderm, but not in the head mesoderm, strongly suggesting that the head meso- derm of extant vertebrates is not segmented. -
Expression Patterns of Neural Genes in Euperipatoides Kanangrensis Suggest Divergent Evolution of Onychophoran and Euarthropod Neurogenesis
Expression patterns of neural genes in Euperipatoides kanangrensis suggest divergent evolution of onychophoran and euarthropod neurogenesis Bo Joakim Eriksson and Angelika Stollewerk1 School of Biological and Chemical Sciences, Queen Mary University of London, London E1 4NS, United Kingdom Edited by Thomas C. Kaufman, Indiana University, Bloomington, IN, and approved November 10, 2010 (received for review June 28, 2010) One of the controversial debates on euarthropod relationships pattern of neurogenesis that has been retained in these groups centers on the question as to whether insects, crustaceans, and and thus cannot be used to resolve euarthropod phylogeny? myriapods (Mandibulata) share a common ancestor or whether Analysis of neurogenesis in a closely related group, the Ony- myriapods group with the chelicerates (Myriochelata). The debate chophora, might shed light on this problem. Although the phy- was stimulated recently by studies in chelicerates and myriapods logenetic position of onychophorans is still debated, many that show that neural precursor groups (NPGs) segregate from the phylogenies group them with euarthropods and possibly tardi- neuroectoderm generating the nervous system, whereas in insects grades in the phylum Arthropoda; thus onychophorans share and crustaceans the nervous tissue is produced by stem cells. Do a common ancestor with euarthropods (8, 19–23). Analyses of the shared neural characters of myriapods and chelicerates repre- neurogenesis in onychophorans suggests that, similar to insects sent derived characters that support the Myriochelata grouping? and crustaceans, single neural precursors are formed in the neu- Or do they rather reflect the ancestral pattern? Analyses of neuro- roectoderm, rather than groups of cells as seen in chelicerates and genesis in a group closely related to euarthropods, the onycho- myriapods (24–26). -
Quantitative Study of Developmental Biology Confirms Dickinsonia As a Metazoan
1 Quantitative study of developmental biology confirms Dickinsonia 2 as a metazoan 3 4 Renee S. Hoekzema a,b,1, Martin D. Brasier b,†, Frances S. Dunn c,d, and Alexander G. Liuc,e,1 5 6 a Department of Mathematics, University of Oxford, Radcliffe Observatory Quarter, 7 Woodstock Road, Oxford, OX2 6GG, UK. 8 b Department of Earth Sciences, University of Oxford, South Parks Road, Oxford, OX1 3AN, 9 UK. 10 c School of Earth Sciences, University of Bristol, Life Sciences Building, 24 Tyndall Avenue, 11 Bristol, BS8 1TQ, UK. 12 d British Geological Survey, Nicker Hill, Keyworth, NG12 5GG, UK. 13 e Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge, CB2 14 3EQ, UK. 15 1To whom correspondence may be addressed. Email: [email protected] or 16 [email protected] 17 † Deceased. 18 19 Keywords. Metazoan evolution, bilaterian, Ediacaran, development, ontogeny 20 The late Ediacaran soft-bodied macro-organism Dickinsonia (age range ~560–550Ma) 21 has often been interpreted as an early animal, and is increasingly invoked in debate on 22 the evolutionary assembly of eumetazoan bodyplans. However, conclusive positive 23 evidence in support of such a phylogenetic affinity has not been forthcoming. Here we 24 subject a collection of Dickinsonia specimens interpreted to represent multiple 25 ontogenetic stages to a novel, quantitative method for studying growth and development 26 in organisms with an iterative bodyplan. Our study demonstrates that Dickinsonia grew 27 via pre-terminal ‘deltoidal’ insertion and inflation of constructional units, followed by a 28 later inflation-dominated phase of growth. -
A Study of Metamerism
A STUDY OP METAMERISM. 395 A Study of Metamerism. By T. H. Morgan, Ph.D., Associate Professor of Biology, Bryn Mawr College, U.S.A. With Plates 40—43. TABLE OF CONTENTS. PAGE I. Typical Forms of Modification in Annelids .... 395 II. Variation in the Position of the Reproductive Organs . 403 III. Abnormalities in Front of or including the 15th Metamere . 407 IV. Study of Embryos 418 V. Abnormalities at the Posterior End 421 VI. Modification of Internal Structures 425 VII. Study of Polychsetous Annelids and Leeches .... 428 VIII. Summary 431 IX. Modifications in Antenna of Arthropods ..... 435 X. Abnormal Metamerism of Locust 437 XL Study of Colour-bands of Echinoderms 439 XII. Regeneration in Earthworms 445 XIII. General Conclusions 460 I. TYPICAL FOEMS OF MODIFICATION. THAT there were occasionally to be found in the Annelids irregularities in the serial repetition of the rings seems to have been known to several of the earlier writers on descriptive and systematic zoology. The fact did not attract more than a passing attention, and such irregularities were relegated to that waste-heap of abnormalities from which subsequent in- vestigation has often drawn valuable material. Simultaneously in 1892 two articles appeared dealing with 396 T. H. MORGAN. these abnormal conditions, one by C. J. Cori (13), and the other by the present writer (33). Both writers pointed out the general interest attached to these modifications, and their importance for an interpretation of the general problem of metamerism. Subsequently a third paper appeared (10), re- cording the presence of similar abnormalities in many groups of Annelids, but without making any attempt to solve the problem itself. -
Cephalic Neurulation in the Mouse Embryo Analyzed by SEM and Morphometry
THE ANATOMICAL RECORD 203:375-396 (1982) Cephalic Neurulation in the Mouse Embryo Analyzed by SEM and Morphometry ANTONE G. JACOBSON AND PATRICK P.L. TAM Department of Zoology. Uniuersity of Texas, Austin, TX 78712 (A.G.J.) and Department of Anatomy, (‘hinese University of Hong Kong, Shatin, N.T., Hong Kong IP.PL.T) ABSTRACT A detailed account of mouse neurulation is given based mostly on SEM analysis over 20 hr of development. Many observations and measure- ments were made on staged living embryos and on embryos prepared for scanning and light microscopy to help deduce what mechanisms may contribute to neural tube formation. Each lateral half of the early cephalic neural plate makes a convex bulge, opposite to the way it must fold to form a tube. Underlying mesenchyme and matrix are reported to have a role in forming these bulges. Processes that form the tube must overcome this opposed folding and the forces that produce it. Crani- al flexure begins long before tube formation. The flexure commences at the rostra1 tip of the cephalic neural plate, then the apex of the flexure migrates caudally to the mesencephalic region. Early appearance of this flexure imposes a mechanical impediment to tube closure in forebrain and midbrain regions. Tube closure begins in the cervical region exactly where the neural plate is reflected dorsally by a bend in the embryo. This bend may mechanically assist closure in this region. Cells of the mouse neural plate are reported to contain organized microfilaments and mi- crotubules, and the plate cells appear to change shape (reduce apical area and in- crease cell height) in the same manner as that suggested in embryos of some other species to contribute to neural tube formation. -
R-Cadherin Expression During Nucleus Formation in Chicken Forebrain Neuromeres
The Journal of Neuroscience, June 1995, 15(6): 4157-4172 R-Cadherin Expression during Nucleus Formation in Chicken Forebrain Neuromeres Susanne I. I. GBnzler and Christoph Redies Department of Biochemistry, Max Planck Institute for Developmental Biology, D-72072 Tiibingen, Germany The primordial neuroepithelium of the vertebrate forebrait dahl, 1924; Vaage, 1969; Kuhlenbeck, 1973; Puelleset al., 1987; consists of transverse and longitudinal morphogenetic Puelles and Rubenstein, 1993) that represent independentmor- compartments (“neuromeres”). During development, neu- phogenetic fields (Bergquist and KallCn, 1953a,b, 1954; Keyser, rons born in the ventricular zone of each neuromere mi- 1972; Puelleset al., 1987). The boundariesbetween neuromeres grate outward to the mantle zone. Here, neuroblasts grad- often coincide with primordial fiber tracts and restrict cell lin- ually accumulate and aggregate either into sheets (“lami- eage and migration. Generally, they coincide with the borders nae”) or into roundish structures (“nuclei”). As brain ar- of expressionof generegulatory proteins (reviewed in Lumsden, chitecture matures, sets of nuclei and laminae derived from 1990, 1993; Figdor and Stern, 1993; Krumlauf et al., 1993; Puel- several neuromeres become connected by fiber tracts to les and Rubenstein, 1993; Wilson et al., 1993). form functional circuits. We show by immunostaining and During development, a percentageof cells born in the prolif- in situ hybridization techniques that, in the E3-E5 chicken erative (ventricular) zone of each neuromerebecome postmitotic embryo, the cell adhesion molecule R-cadherin is ex- and migrate as neuroblastsoutward into the mantle zone (Sauer, pressed in several stripes and patches in the forebrain neu- 1935; Fujita, 1964; Morest, 1970) in two or three sustained roepithelium. -
Homeotic Gene Action in Embryonic Brain Development of Drosophila
Development 125, 1579-1589 (1998) 1579 Printed in Great Britain © The Company of Biologists Limited 1998 DEV1254 Homeotic gene action in embryonic brain development of Drosophila Frank Hirth, Beate Hartmann and Heinrich Reichert* Institute of Zoology, University of Basel, Rheinsprung 9, CH-4051 Basel, Switzerland *Author for correspondence (e-mail: [email protected]) Accepted 18 February; published on WWW 1 April 1998 SUMMARY Studies in vertebrates show that homeotic genes are absence of labial, mutant cells are generated and positioned involved in axial patterning and in specifying segmental correctly in the brain, but these cells do not extend axons. identity of the embryonic hindbrain and spinal cord. To Additionally, extending axons of neighboring wild-type gain further insights into homeotic gene action during CNS neurons stop at the mutant domains or project ectopically, development, we here characterize the role of the homeotic and defective commissural and longitudinal pathways genes in embryonic brain development of Drosophila. We result. Immunocytochemical analysis demonstrates that first use neuroanatomical techniques to map the entire cells in the mutant domains do not express neuronal anteroposterior order of homeotic gene expression in the markers, indicating a complete lack of neuronal identity. Drosophila CNS, and demonstrate that this order is An alternative glial identity is not adopted by these mutant virtually identical in the CNS of Drosophila and mammals. cells. Comparable effects are seen in Deformed mutants but We then carry out a genetic analysis of the labial gene in not in other homeotic gene mutants. Our findings embryonic brain development. Our analysis shows that demonstrate that the action of the homeotic genes labial loss-of-function mutation and ubiquitous overexpression of and Deformed are required for neuronal differentiation in labial results in ectopic expression of neighboring the developing brain of Drosophila. -
The Antennae Serve for Locomotion. the Internal Organization Includes
ID SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I3I The antennae serve for locomotion. The internal organization includes usually an alimentary canal, a muscular system, a nervous system, and a pair of antennal excretory glands. The alimentary canal when fully developed consists of an endodermal mesenteron and an ectodermal stomodaeum and proctodaeum. The mouth is concealed above a large labrum; the anus is usually formed at a later stage. The nervous system includes three pairs of ganglia corresponding to the append ages. Though there is no visible segmentation in the ectoderm, the presence of appendages and ganglia shows that the nauplius is at FIG. 2.—Nauplius and metanauplius of Apus cancriformis Bosc (from Qaus, 1873). A, nauplius, with first antennae {lAnt), second antennae {sAnt), and man dibles (Md), rudiments of teloblastic appendages seen through cuticle. B, metanauplius, appendages of teloblastic segments (tbSegs) exposed after first moult. least a partly segmented stage of development. The region of the body behind the mandibles is that in which later the other segments will be formed, and their rudiments may be seen beneath the naupliar cuticle. When these segments are formed, however, they are generated by a different method from that which formed the anterior segments. The nauplius is derived from a very early stage of embryonic de velopment, represented in species that hatch at a later period by a simple embryo with rudiments of three pairs of appendages. The embryo still in the egg at this stage is clearly more simple in its structure than is the nauplius. The nauplius, therefore, is not merely an early hatched embryo—it has undergone a metamorphosis before hatching to adapt it to a free life in the water.