DOCSLIB.ORG

The Parasitic Coelenterate, Polypodium Hydriforme Ussov, from the Eggs of the American Acipenseri from Polyodon Spathula

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
The Parasitic Coelenterate, Polypodium Hydriforme Ussov, from the Eggs of the American Acipenseri from Polyodon Spathula University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln US Fish & Wildlife Publications US Fish & Wildlife Service 1979 The Parasitic Coelenterate, Polypodium hydriforme Ussov, from the Eggs of the American Acipenseri from Polyodon spathula Glenn L. Hoffman US Fish and Wildlife Service E. V. Raikova Institute of Cytology of the Academy of Sciences, Leningrad V. Ch. Suppes Missouri Department of Conservation, Sweet Springs Follow this and additional works at: https://digitalcommons.unl.edu/usfwspubs Part of the Aquaculture and Fisheries Commons Hoffman, Glenn L.; Raikova, E. V.; and Suppes, V. Ch., "The Parasitic Coelenterate, Polypodium hydriforme Ussov, from the Eggs of the American Acipenseri from Polyodon spathula" (1979). US Fish & Wildlife Publications. 115. https://digitalcommons.unl.edu/usfwspubs/115 This Article is brought to you for free and open access by the US Fish & Wildlife Service at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in US Fish & Wildlife Publications by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. The Journal of Parasitology, Vol. 65, No. 5 (Oct., 1979), pp. 804-810 J. Parasitol., 65(5), 1979, pp. 804-810 ? American Society of Parasitologists 1979 THE PARASITIC COELENTERATE, POLYPODIUM HYDRIFORME USSOV, FROM THE EGGS OF THE AMERICAN ACIPENSERIFORM POLYODON SPATHULA E. V. Raikova,* V. Ch. Suppes,t and G. L. Hoffmant ABSTRACT: No significant differences in macro- and micromorphology were found between the parasitic stolon and free-living polyps of Polypodium sp. obtained from infected eggs of the North American aci- penseriform fish Polyodon spathula and corresponding developmental stages of Polypodium hydriforme Ussov, parasitic in the Volga sterlet (Acipenser ruthenus). Therefore, both the American and the European forms of Polypodium belong to the species P. hydriforme Ussov. For a century, the coelenterate Polypodium found in Romania (Bogatu, 1961) and in Iran hydriforme Ussov, parasitic in the eggs of (Nechat and Mokhayer, 1974). acipenserid fishes, was considered a "purely A discovery in 1970 of Polypodium on the Russian" animal. It was discovered in 1871 by American continent in the eggs of the stur- Ovsjannikov in the eggs of the Volga sterlet, geon Acipenser fulvescens inhabiting the (Acipenser ruthenus L.), and for more than 70 Great Lakes (Hoffman et al., 1974), was there- years thereafter, it appeared to be confined to fore a distinct surprise. Thereafter (in 1973), that host species and that river. Only after the Polypodium also was found in the eggs of sev- beginning of extensive ichthyoparasitological eral specimens of the American acipenseri- research in the USSR was it found in other form Polyodon spathula, a representative of hosts and other watersheds (Dogiel, 1940). the family Polyodontidae which belongs, with During the last 40 years, P. hydriforme has the family Acipenseridae, to the order Aci- been found in practically all rivers of the Eu- penseriformes (Suppes and Meyer, 1975). ropean part of the USSR inhabited by Acipen- Thus, the range of the hosts of Polypodium seridae, and also in the tributaries of the Aral has exceeded the Acipenseridae, and its area, Sea and in the Amur River of the Far East. All the Eurasian continent. We describe here the acipenserid species occurring in the USSR American form of Polypodium from Polyodon, except the Siberian sterlet (A. ruthenus ruth- compare it with the typical P. hydriforme, and enus natio marsiglii Brandt), the Siberian provide evidence that the American form is sturgeon (A. baeri Brandt), and the Atlantic probably the same species. sturgeon (A. sturio L.), proved to be hosts of MATERIALSAND METHODS P. hydriforme. It has been found in Acipenser ruthenus L. (the European sterlet), A. giil- Our material consisted of both Polypodium-in- denstiidti Brandt (the Russian sturgeon), A. fected and healthy eggs of Polyodon spathula, ob- stellatus Pallas A. nudiventris tained from 8 females caught in March, April, and (the sevrjuga), May 1973 and October 1974 in the Osage River, Lovetzky (the ship), A. schrenki Brandt (the Missouri. The infected eggs in 5 females caught in Amur sturgeon), Huso huso (L.) (the beluga), March and April belonged to the older generation and H. dauricus (Georgi) (the kaluga) (Dogiel, of oocytes. These were nearly mature and corre- 1940; Markov and Trussov, 1966; Svirsky, sponded to the Stage IV-V of Nedoshivin's (1928) scale. Two 22 and 1967). Outside the USSR, P. hydriforme was females, caught April May 11, were already in the post-spawning period and con- tained no Polypodium; one female, caught in Oc- tober 1974 and infected with Polypodium, was at Received for publication 1 November 1978. Stage IV of oocyte development (eggs due to be * Institute of Cytology of the Academy of Sciences, spawned next spring). The oocytes were fixed Leningrad 190121, USSR. either with 10% formalin or with Gilson's fluid. ? Missouri Department of Conservation, Sweet Some of the oocytes were infected with the micro- Springs, Missouri 65351, USA. sporidian Pleistophora sulci Rasin 1936, 1949 and in ad- $ Fish Farming Experimental Station, Stuttgart, (Sprague Vavra, 1977) (Cocconema sulci) Arkansas 72160, USA. dition to Polypodium. 804 RAIKOVAET AL.-PARASITIC COELENTERATEFROM EGGS OF POLYODON 805 Free-living polyps, raised from stolons infecting ly the zona radiata and the follicular enve- the were cultivated in Petri dishes and oocytes lope-grow thinner (Figs. 1, 2). fixed with 10% formalin at various ages (from their emergence out of the oocytes through a period of The entodermal cells (i.e., cells of the outer 40 days of free life). layer of the stolon) are flagellated, but the fla- For histological investigation, some formalin- gella appear poorly preserved after formalin fixed and infected eggs free-living polyps were re- fixation. At places lacking the enveloping cap- fixed with Zenker's and Bouin's fluids and embed- the entodermal cells ded in paraffin.Sections (7 thick) were stained sule, contain yolk parti- with Heidenhain's "azan," iron/ln hematoxylin, May- cles, which they apparently ingested (Fig. 4). er's hemalum, or by the Feulgen technique. For- Groups of protein-secreting glandular cells malin-fixed material was also used to prepare whole also occur in the entoderm. They are usually mounts of both stolon and which were polyps, in folds of the stolon (Fig. 5) and therefore mounted in glycerin-gelatin. contact neither the capsule nor the yolk. The ectodermal RESULTS (inner layer) cells (Fig. 6) have small nuclei located in their basal ends, Unambiguous determination of the specific large vacuoles occupying the cells' middle identity of the American Polypodium proved parts, and an apical cytoplasm of reticular ap- difficult because only some stages of its de- pearance. In Volga Polypodium, the meshes velopment were present in our material. of this reticulum contained granules of acid Moreover, no species criteria distinct from mucopolysaccharide, which formed together generic ones exist for Polypodium, the genus an apical layer of the ectoderm (Raikova, always having been monotypic. Therefore, we 1960). It seems that these granules were not present here a detailed description of the preserved in the American material with the available developmental stages of the Amer- fixatives used (Fig. 6). The ectodermal epi- ican Polypodium, in order to compare them thelial cells are underlain by muscle cells, with the respective stages of P. hydriforme which are independent and not muscle parts from the type host, the Volga sterlet (Raikova, of epithelio-muscular cells (Figs. 6, 7). 1958, 1960, 1961, 1973). Sections through infected Stage IV-V eggs The parasitic stages of Polypodium found clearly show tentacles inside the stolon (Figs. in our material were represented by two-lay- 1, 3). These are everted-i.e., their ectoderm ered stolons inside oocytes of both Stages IV is inside and their entoderm is outside. The (October) and IV-V (March-April). In Stage tentacular ectoderm contains numerous cni- IV-V oocytes, the stolon occupies the entire docysts of various size classes. Both walking periperal part of an oocyte, the yolk and the tentacles and sensory tentacles can be seen- nucleus being shifted to its center (Fig. 1). the walking tentacles containing only large The two germ layers of the stolon are invert- (10 1m in diameter) and sometimes small (5 ed. The entoderm is the outermost layer, fac- 1tm) cnidocysts, and the sensory tentacles ing the surrounding yolk, and the ectodermn containing medium-sized (7 and small Itm) lines the inner cavity of the stolon, which con- enidocysts (Figs. 6-9). The ectoderm is un- tains the tentacles. An additional dense layer derlain with muscle cells, whereas the ento- covers the parasite, but not continuously (Fig. derm forms a dense axial rod in each tentacle 2); it contains elongated nuclei and inclusions (Figs. 1, 3, 7-9). In some sections this rod of ingested yolk particles. This incomplete seems to have an inner lumen (Figs. 7, 8), but layer certainly corresponds to remnants of a in most sections it is solid. syncytic envelope, the capsule, peculiar to The earliest of the parasitic stages encoun- Polypodium, which isolates the developing tered in the present study came from the eggs stolon from the yolk, assumes the function of of a Stage IV female caught in October. These yolk digestion, and degenerates when the sto- were stolons with inverted germ layers, as just lon is mature (Raikova, 1960). The nucleus of described, but with continuous capsules the infected oocyte remains visible; it is around them and with a smaller number of strongly lobulated (Figs. 1, 3), and has a tentacles inside them. Also, mature cnidocysts dense, almost fibrous karyoplasm and several were far fewer in the ectoderm of the tenta- vacuolized, frequently fused nucleoli. Usual- cles. The latest stages, found in late April, in- ly no chromosomes are visible in the nucleus. habited eggs ready to be spawned; their cap- The envelopes of the infected egg-especial- sule had, on the contrary, almost disappeared, 806 THE JOURNAL OF PARASITOLOGY,VOL 65, NO.
Load more

Recommended publications
  • Unesco-Eolss Sample Chapters
    FISHERIES AND AQUACULTURE - Myxozoan Biology And Ecology - Dr. Ariadna Sitjà-Bobadilla and Oswaldo Palenzuela MYXOZOAN BIOLOGY AND ECOLOGY Ariadna Sitjà-Bobadilla and Oswaldo Palenzuela Instituto de Acuicultura Torre de la Sal, Consejo Superior de Investigaciones Científicas (IATS-CSIC), Castellón, Spain Keywords: Myxozoa, Myxosporea, Actinosporea, Malacosporea, Metazoa, Parasites, Fish Pathology, Invertebrates, Taxonomy, Phylogeny, Cell Biology, Life Cycle Contents 1. Introduction 2. Phylogeny 3. Morphology and Taxonomy 3.1. Spore Morphology 3.2. Taxonomy 4. Life Cycle 4.1. Life Cycle of Myxosporea 4.2. Life Cycle of Malacosporea 5. Cell Biology and Development 6. Ecological Aspects 6.1. Hosts 6.2. Habitats 6.3. Environmental Cues 7. Pathology 7.1. General Remarks 7.2. Pathogenic Effects of Myxozoans 7.2.1. Effects on Invertebrates 7.2.2. Effects on Fish 7.2.3. Effects on non-fish Vertebrates Acknowledgements Glossary Bibliography Biographical Sketches Summary UNESCO-EOLSS The phylum Myxozoa is a group of microscopic metazoans with an obligate endoparasitic lifestyle.SAMPLE Traditionally regarded CHAPTERS as protists, research findings during the last decades have dramatically changed our knowledge of these organisms, nowadays understood as examples of early metazoan evolution and extreme adaptation to parasitic lifestyles. Two distinct classes of myxozoans, Myxosporea and Malacosporea, are characterized by profound differences in rDNA evolution and well supported by differential biological and developmental features. This notwithstanding, most of the existing Myxosporea subtaxa require revision in the light of molecular phylogeny data. Most known myxozoans exhibit diheteroxenous cycles, alternating between a vertebrate host (mostly fish but also other poikilothermic vertebrates, and exceptionally birds and mammals) and an invertebrate (mainly annelids and bryozoans but possibly other ©Encyclopedia of Life Support Systems (EOLSS) FISHERIES AND AQUACULTURE - Myxozoan Biology And Ecology - Dr.
    [Show full text]
  • Petition to List US Populations of Lake Sturgeon (Acipenser Fulvescens)
    Petition to List U.S. Populations of Lake Sturgeon (Acipenser fulvescens) as Endangered or Threatened under the Endangered Species Act May 14, 2018 NOTICE OF PETITION Submitted to U.S. Fish and Wildlife Service on May 14, 2018: Gary Frazer, USFWS Assistant Director, [email protected] Charles Traxler, Assistant Regional Director, Region 3, [email protected] Georgia Parham, Endangered Species, Region 3, [email protected] Mike Oetker, Deputy Regional Director, Region 4, [email protected] Allan Brown, Assistant Regional Director, Region 4, [email protected] Wendi Weber, Regional Director, Region 5, [email protected] Deborah Rocque, Deputy Regional Director, Region 5, [email protected] Noreen Walsh, Regional Director, Region 6, [email protected] Matt Hogan, Deputy Regional Director, Region 6, [email protected] Petitioner Center for Biological Diversity formally requests that the U.S. Fish and Wildlife Service (“USFWS”) list the lake sturgeon (Acipenser fulvescens) in the United States as a threatened species under the federal Endangered Species Act (“ESA”), 16 U.S.C. §§1531-1544. Alternatively, the Center requests that the USFWS define and list distinct population segments of lake sturgeon in the U.S. as threatened or endangered. Lake sturgeon populations in Minnesota, Lake Superior, Missouri River, Ohio River, Arkansas-White River and lower Mississippi River may warrant endangered status. Lake sturgeon populations in Lake Michigan and the upper Mississippi River basin may warrant threatened status. Lake sturgeon in the central and eastern Great Lakes (Lake Huron, Lake Erie, Lake Ontario and the St. Lawrence River basin) seem to be part of a larger population that is more widespread.
    [Show full text]
  • Ecosystem Diversity Report George Washington National Forest Draft EIS April 2011
    Appendix E Ecosystem Diversity Report George Washington National Forest Draft EIS April 2011 U.S. Department of Agriculture Forest Service Southern Region Ecosystem Diversity Report George Washington National Forest April 2011 Appendix E Ecosystem Diversity Report George Washington National Forest Draft EIS April 2011 Table of Contents TABLE OF CONTENTS .............................................................................................................. I 1.0 INTRODUCTION.................................................................................................................. 1 2.0 ECOLOGICAL SUSTAINABILITY EVALUATION PROCESS ................................... 3 3.0 ECOLOGICAL SYSTEMS .................................................................................................. 7 3.1 Background and Distribution of Ecosystems ..................................................................................................... 7 North-Central Appalachian Acidic Swamp ............................................................................................................ 10 3.2 Descriptions of the Ecological Systems ............................................................................................................ 10 3.2.1 Spruce Forest: Central and Southern Appalachian Spruce-Fir Forest .......................................................... 10 3.2.2 Northern Hardwood Forest : Appalachian (Hemlock)- Northern Hardwood Forest ..................................... 11 3.2.3 Cove Forest: Southern and Central
    [Show full text]
  • Evolution, Origins and Diversification of Parasitic Cnidarians
    1 Evolution, Origins and Diversification of Parasitic Cnidarians Beth Okamura*, Department of Life Sciences, Natural History Museum, Cromwell Road, London SW7 5BD, United Kingdom. Email: [email protected] Alexander Gruhl, Department of Symbiosis, Max Planck Institute for Marine Microbiology, Celsiusstraße 1, 28359 Bremen, Germany *Corresponding author 12th August 2020 Keywords Myxozoa, Polypodium, adaptations to parasitism, life‐cycle evolution, cnidarian origins, fossil record, host acquisition, molecular clock analysis, co‐phylogenetic analysis, unknown diversity Abstract Parasitism has evolved in cnidarians on multiple occasions but only one clade – the Myxozoa – has undergone substantial radiation. We briefly review minor parasitic clades that exploit pelagic hosts and then focus on the comparative biology and evolution of the highly speciose Myxozoa and its monotypic sister taxon, Polypodium hydriforme, which collectively form the Endocnidozoa. Cnidarian features that may have facilitated the evolution of endoparasitism are highlighted before considering endocnidozoan origins, life cycle evolution and potential early hosts. We review the fossil evidence and evaluate existing inferences based on molecular clock and co‐phylogenetic analyses. Finally, we consider patterns of adaptation and diversification and stress how poor sampling might preclude adequate understanding of endocnidozoan diversity. 2 1 Introduction Cnidarians are generally regarded as a phylum of predatory free‐living animals that occur as benthic polyps and pelagic medusa in the world’s oceans. They include some of the most iconic residents of marine environments, such as corals, sea anemones and jellyfish. Cnidarians are characterised by relatively simple body‐plans, formed entirely from two tissue layers (the ectoderm and endoderm), and by their stinging cells or nematocytes.
    [Show full text]
  • Phylum Myxozoa) Infecting the Aquatic Fauna
    ULTRASTRUCTURAL AND MOLECULAR DESCRIPTION OF SOME MYXOSPOREANS (PHYLUM MYXOZOA) INFECTING THE AQUATIC FAUNA SÓNIA RAQUEL OLIVEIRA ROCHA Dissertation for Master in Marine Sciences – Marine Resources November 2011 i ii SÓNIA RAQUEL OLIVEIRA ROCHA ULTRASTRUCTURAL AND MOLECULAR DESCRIPTION OF SOME MYXOSPOREANS (PHYLUM MYXOZOA) INFECTING THE AQUATIC FAUNA Dissertation for Master’s degree in Marine Sciences – Marine Resources submitted to the Institute of Biomedical Sciences Abel Salazar, University of Porto. Supervisor – Doctor Carlos Azevedo Category – “Professor Catedrático Jubilado” Affiliation – Institute of Biomedical Sciences Abel Salazar, University of Porto. ii Nota prévia Declaro que, como autora desta tese, estive envolvida na realização de todos os procedimentos laboratoriais conduzentes à obtenção dos resultados aqui apresentados pela primeira vez. A minha actividade desenvolveu-se desde a colheita e diagnóstico preliminar de material biológico para amostragem, à execução do processamento protocolar para microscopia óptica, incluindo contraste de interferência diferencial, microscopia eletrónica de transmissão e microscopia eletrónica de varrimento, à realização dos procedimentos laboratoriais necessários para a biologia molecular. O conteúdo desta tese é da minha autoria, embora inclua as recomendações e sugestões positivamente feitas pelo orientador, colaboradores e técnicos. O trabalho realizado e informação obtida resultaram na elaboração de três artigos científicos distintos, aqui apresentados nos capítulos 2, 3 e 4. Rocha S., Casal G., Matos P., Matos E., Dkhil M. and Azevedo C. 2011: Description of Triangulamyxa psittaca sp. nov. (Myxozoa: Myxosporea), a new parasite in the urinary bladder of Colomesus psittacus (Teleostei) from the Amazon River, with emphasis on the ultrastructure of plasmodial stages. Acta Protozool. 50: (In press) Rocha S., Casal G., Al-Quraishy S.
    [Show full text]
  • Linear Mitochondrial Genome in Anthozoa (Cnidaria): a Case Study in Ceriantharia Received: 11 February 2019 Sérgio N
    www.nature.com/scientificreports OPEN Linear Mitochondrial Genome in Anthozoa (Cnidaria): A Case Study in Ceriantharia Received: 11 February 2019 Sérgio N. Stampar1, Michael B. Broe2, Jason Macrander3,4, Adam M. Reitzel3, Accepted: 4 April 2019 Mercer R. Brugler 5,6 & Marymegan Daly2 Published: xx xx xxxx Sequences and structural attributes of mitochondrial genomes have played a critical role in the clarifcation of relationships among Cnidaria, a key phylum of early-diverging animals. Among the major lineages of Cnidaria, Ceriantharia (“tube anemones”) remains one of the most enigmatic in terms of its phylogenetic position. We sequenced the mitochondrial genomes of two ceriantharians to see whether the complete organellar genome would provide more support for the phylogenetic placement of Ceriantharia. For both Isarachnanthus nocturnus and Pachycerianthus magnus, the mitochondrial gene sequences could not be assembled into a single circular genome. Instead, our analyses suggest that both species have mitochondrial genomes consisting of multiple linear fragments. Linear mitogenomes are characteristic of members of Medusozoa, one of the major lineages of Cnidaria, but are unreported for Anthozoa, which includes the Ceriantharia. The inferred number of fragments and variation in gene order between species is much greater within Ceriantharia than among the lineages of Medusozoa. We identify origins of replication for each of the fve putative chromosomes of the Isarachnanthus nocturnus mitogenome and for each of the eight putative chromosomes of the Pachycerianthus magnus mitogenome. At 80,923 bp, I. nocturnus now holds the record for the largest animal mitochondrial genome reported to date. The novelty of the mitogenomic structure in Ceriantharia highlights the distinctiveness of this lineage but, because it appears to be both unique to and diverse within Ceriantharia, it is uninformative about the phylogenetic position of Ceriantharia relative to other Anthozoa.
    [Show full text]
  • Sturgeon Hatchery Manual
    FAO ISSN 2070-7010 FISHERIES AND 558 AQUACULTURE TECHNICAL PAPER 558 STURGEON HATCHERY MANUAL This Sturgeon Hatchery Manual includes the latest available scientific research findings and experiences and compiles advice given in earlier manuals and handbooks on sturgeon culture and reproduction practices. This document was prepared in response HATC STURGEON to numerous requests for practical guidance on this subject from the Central Asian and Caucasus region to the Food and Agriculture Organization of the United Nations (FAO). This manual is targeted particularly at sturgeon farmers, sturgeon hatchery operators, hatchery technicians, and fisheries and aquaculture managers involved in sturgeon aquaculture development and the restocking and rehabilitation of sturgeon populations in the countries around the basins of the Black and Caspian seas. It aims to provide a practical handbook of modern sturgeon hatchery practices and management. The H manual is available in the English, Russian and Turkish languages. MANUAL ERY FAO FAO Sturgeon Hatchery FISHERIES AND Manual AQUACULTURE TECHNICAL PAPER 558 Prepared by Mikhail S. Chebanov FAO Consultant Krasnodar, Russia and Elena V. Galich Krasnodar, Russia FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS Ankara, 2013 Reprinted 2013 The designations employed and the presentation of material in this information product do not imply the expression of any opinion whatsoever on the part of the Food and Agriculture Organization of the United Nations (FAO) concerning the legal or development status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. The mention of specific companies or products of manufacturers, whether or not these have been patented, does not imply that these have been endorsed or recommended by FAO in preference to others of a similar nature that are not mentioned.
    [Show full text]
  • A Floristic Study of Polylepis Forest Fragments in the Central Andes of Ecuador
    A FLORISTIC STUDY OF POLYLEPIS FOREST FRAGMENTS IN THE CENTRAL ANDES OF ECUADOR Ulrika Ridbäck Examensarbete i biologi, 15 hp, 2008 Handledare: Bertil Ståhl ___________________________________________________________________________ Institutionen för kultur, energi och miljö Högskolan på Gotland/Gotland University, SE-621 67 Visby www.hgo.se CONTENTS RESUMEN/ABSTRACT ……………………………………………………….....2 INTRODUCTION……………………………………………………...…....…......3 Background……………………………………………………...……………….....3 The genus Polylepis ……………………………………………………...………....3 Earlier studies……………………………………………………...………………..4 Why are Polylepis forests important? ………………………………………...…....5 Objectives……………………………………………………...……………...……5 STUDY AREA……………………………………………………...………...........6 Oyacachi……………………………………………………...…………………….6 Climate……………………………………………………...………………………7 MATERIAL AND METHODS………………………………………………...…..8 RESULTS…………………………………………………………………………...9 Observations of the remnants of Polylepis pauta forests…………………………...9 Species richness of vascular plants………………………………………………....9 Phytogeography…………………………………………………………………....10 Endemism………………………………………………………………………….10 Remnant of Polylepis microphylla forest at Achupallas…………………………..10 DISCUSSION……………………………………………………...………...........11 Species richness…………………………………………………………………...11 Conservation………………………………………………………………………11 Different Polylepis forests………………………………………………………...13 Reforestation……………………………………………………………………....13 Further studies…………………………………………………………………….14 ACKNOWLEDGEMENTS………………………………………………………14 REFERENCES.…………………………………………………………………...14
    [Show full text]
  • Diversity and Evolution of Myxozoan Minicollagens and Nematogalectins
    Diversity and evolution of myxozoan minicollagens and nematogalectins The Harvard community has made this article openly available. Please share how this access benefits you. Your story matters Citation Shpirer, Erez, E Sally Chang, Arik Diamant, Nimrod Rubinstein, Paulyn Cartwright, and Dorothée Huchon. 2014. “Diversity and evolution of myxozoan minicollagens and nematogalectins.” BMC Evolutionary Biology 14 (1): 205. doi:10.1186/s12862-014-0205-0. http://dx.doi.org/10.1186/s12862-014-0205-0. Published Version doi:10.1186/s12862-014-0205-0 Citable link http://nrs.harvard.edu/urn-3:HUL.InstRepos:13347482 Terms of Use This article was downloaded from Harvard University’s DASH repository, and is made available under the terms and conditions applicable to Other Posted Material, as set forth at http:// nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of- use#LAA Shpirer et al. BMC Evolutionary Biology 2014, 14:205 http://www.biomedcentral.com/1471-2148/14/205 RESEARCH ARTICLE Open Access Diversity and evolution of myxozoan minicollagens and nematogalectins Erez Shpirer1, E Sally Chang2, Arik Diamant3, Nimrod Rubinstein4, Paulyn Cartwright2* and Dorothée Huchon1* Abstract Background: Myxozoa are a diverse group of metazoan parasites with a very simple organization, which has for decades eluded their evolutionary origin. Their most prominent and characteristic feature is the polar capsule: a complex intracellular structure of the myxozoan spore, which plays a role in host infection. Striking morphological similarities have been found between myxozoan polar capsules and nematocysts, the stinging structures of cnidarians (corals, sea anemones and jellyfish) leading to the suggestion that Myxozoa and Cnidaria share a more recent common ancestry.
    [Show full text]
  • York County Natural Areas Inventory
    YORK COUNTY NATURAL AREAS INVENTORY A COMPONENT OF THE YORK COUNTY COMPREHENSIVEPLAN PAGE INTENTIONALLY BLANK YORK COUNTY NATURAL AREAS INVENTORY York County Planning Commission www.ycpc.org September, 1997 Amended - October 27, 2004 The original Natural Areas Inventory was funded in part by a Keystone, Park and Conservation Fund Program Grant from the Pennsylvania Department of Conservation and Natural Resources and a Community Development Block Grant from York County. PAGE INTENTIONALLY BLANK TABLE OF CONTENTS PAGE Preface ..................................................................... iii Chapter I - Introduction ..........................................................1 Uses For The York County NAI .............................................3 Chapter II - Natural History Overview of The County ....................................5 Physiography and Geology ..................................................5 Soils ..................................................................6 Vegetation ..............................................................8 Disturbance ............................................................11 Chapter III - Pennsylvania Natural Diversity Inventory Data System ........................13 Natural Areas Inventory Methods ............................................14 Information Gathering .....................................................14 Map and Air Photo Interpretation ............................................14 Field Work ............................................................15
    [Show full text]
  • Life Cycle Studies and Transmission Mechanisms of Myxozoan Parasites
    Life cycle studies and transmission mechanisms of myxozoan parasites Den Naturwissenschaftlichen Fakultäten der Friedrich-Alexander- Universität Erlangen-Nürnberg zur Erlangung des Doktorgrades vorgelegt von Dennis Marc Kallert aus Erlangen Als Dissertation genehmigt von den Naturwissenschaftlichen Fakultäten der Friedrich-Alexander-Universität Erlangen-Nürnberg Tag der mündlichen Prüfung: 3. März 2006 Vorsitzender der Prüfungskommission: Prof. Dr. D.-P. Häder Erstberichterstatter: Prof. Dr. W. Haas Zweitberichterstatter: Prof. Dr. Dr. M. El-Matbouli -Contents- Contents ABBREVIATIONS 5 I. INTRODUCTION 6 1. The Phylum Myxozoa Grassé 1970: Common features 6 2. Current knowledge on myxozoan life cycles 8 3. Host invasion by actinospores 10 II. MATERIALS & METHODS 12 1. Animals and parasite cultivation 12 1.1. Fish for experimental infections 12 1.2. Oligochaetes 12 1.3. Parasites 13 1.4. Animals for substrate isolation 14 2. Experimental infections 14 2.1. Henneguya nuesslini Schuberg & Schröder 1905 14 2.2. Myxobolus parviformis sp.n. 16 3. Viability assay 17 4. Discharge experiments 18 4.1. Test substrates 18 4.2. Experimental set-up 19 4.2.1. Test for mechanical and chemical stimuli 19 4.2.2. Bulk experiments 20 4.2.3. Frequency dependency 21 4.2.4. Ca2+ dependency 22 5. Cinematography of polar filament discharge 22 6. Sporoplasm emission 22 7. Mucus fractionation 23 7.1. Heat and incubation 23 7.2. Ashing 23 7.3. Acetone precipitation 24 - 1 - -Contents- 7.4. Alcian blue precipitation 24 7.5. Fluorescamin derivatisation 24 7.6. Extraction with activated charcoal 25 7.7. Lipid extraction 25 7.7.1. Ether-extraction 25 7.7.2.
    [Show full text]
  • The Phylogenetic Placement of Two Enigmatic Metazoan Parasites: Polypodium Hydriforme and Myxozoa
    The phylogenetic placement of two enigmatic metazoan parasites: Polypodium hydriforme and Myxozoa by Nathaniel M. Evans Submitted to the graduate degree program in the Department of Ecology and Evolutionary Biology and the Graduate Faculty of the University of Kansas in partial fulfillment of the requirements for the degree of Master’s of Arts. Dr. Paulyn Cartwright ____ Chairperson Committee members Dr. Kirsten Jensen ____ Dr. Edward Wiley ____ Date defended: 7/14/09 ____ 2 The Thesis Committee for Nathaniel M. Evans certifies that this is the approved Version of the following thesis: The phylogenetic placement of two enigmatic metazoan parasites: Polypodium hydriforme and Myxozoa Committee: Dr. Paulyn Cartwright ____ Chairperson Dr. Kirsten Jensen ____ Dr. Edward Wiley ____ Date approved: 7/15/09 ____ 3 ACKNOWLEDGEMNTS This work would not have been possible without the help of many people who generously and selflessly provided their precious time, resources, and knowledge. First and foremost among these was my advisor, Paulyn Cartwright, who not only helped me successfully navigate this research but who also, over the last several years, has consistently and sincerely made my development as a scientist a significant priority in her life. Paulyn provided my first experience of a truly open dialogue on scientific theories, principles, and methods. For this I will remain indebted to her. I thank her for all her support, encouragement and patience. I would also like to thank Kirsten Jensen and Ed Wiley, for taking time to serve on my committee, administer my oral exam and provide thoughtful comments on my work. I thank all members of the Cartwright lab for their help and friendship during my time in Kansas.
    [Show full text]