Branches on the Tree of Life: Protists
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Molecular Data and the Evolutionary History of Dinoflagellates by Juan Fernando Saldarriaga Echavarria Diplom, Ruprecht-Karls-Un
Molecular data and the evolutionary history of dinoflagellates by Juan Fernando Saldarriaga Echavarria Diplom, Ruprecht-Karls-Universitat Heidelberg, 1993 A THESIS SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY in THE FACULTY OF GRADUATE STUDIES Department of Botany We accept this thesis as conforming to the required standard THE UNIVERSITY OF BRITISH COLUMBIA November 2003 © Juan Fernando Saldarriaga Echavarria, 2003 ABSTRACT New sequences of ribosomal and protein genes were combined with available morphological and paleontological data to produce a phylogenetic framework for dinoflagellates. The evolutionary history of some of the major morphological features of the group was then investigated in the light of that framework. Phylogenetic trees of dinoflagellates based on the small subunit ribosomal RNA gene (SSU) are generally poorly resolved but include many well- supported clades, and while combined analyses of SSU and LSU (large subunit ribosomal RNA) improve the support for several nodes, they are still generally unsatisfactory. Protein-gene based trees lack the degree of species representation necessary for meaningful in-group phylogenetic analyses, but do provide important insights to the phylogenetic position of dinoflagellates as a whole and on the identity of their close relatives. Molecular data agree with paleontology in suggesting an early evolutionary radiation of the group, but whereas paleontological data include only taxa with fossilizable cysts, the new data examined here establish that this radiation event included all dinokaryotic lineages, including athecate forms. Plastids were lost and replaced many times in dinoflagellates, a situation entirely unique for this group. Histones could well have been lost earlier in the lineage than previously assumed. -
Colonial Tunicates: Species Guide
SPECIES IN DEPTH Colonial Tunicates Colonial Tunicates Tunicates are small marine filter feeder animals that have an inhalant siphon, which takes in water, and an exhalant siphon that expels water once it has trapped food particles. Tunicates get their name from the tough, nonliving tunic formed from a cellulose-like material of carbohydrates and proteins that surrounds their bodies. Their other name, sea squirts, comes from the fact that many species will shoot LambertGretchen water out of their bodies when disturbed. Massively lobate colony of Didemnum sp. A growing on a rope in Sausalito, in San Francisco Bay. A colony of tunicates is comprised of many tiny sea squirts called zooids. These INVASIVE SEA SQUIRTS individuals are arranged in groups called systems, which form interconnected Star sea squirts (Botryllus schlosseri) are so named because colonies. Systems of these filter feeders the systems arrange themselves in a star. Zooids are shaped share a common area for expelling water like ovals or teardrops and then group together in small instead of having individual excurrent circles of about 20 individuals. This species occurs in a wide siphons. Individuals and systems are all variety of colors: orange, yellow, red, white, purple, grayish encased in a matrix that is often clear and green, or black. The larvae each have eight papillae, or fleshy full of blood vessels. All ascidian tunicates projections that help them attach to a substrate. have a tadpole-like larva that swims for Chain sea squirts (Botryloides violaceus) have elongated, less than a day before attaching itself to circular systems. Each system can have dozens of zooids. -
Swimming with Protists: Perception, Motility and Flagellum Assembly
REVIEWS Swimming with protists: perception, motility and flagellum assembly Michael L. Ginger*, Neil Portman‡ and Paul G. McKean* Abstract | In unicellular and multicellular eukaryotes, fast cell motility and rapid movement of material over cell surfaces are often mediated by ciliary or flagellar beating. The conserved defining structure in most motile cilia and flagella is the ‘9+2’ microtubule axoneme. Our general understanding of flagellum assembly and the regulation of flagellar motility has been led by results from seminal studies of flagellate protozoa and algae. Here we review recent work relating to various aspects of protist physiology and cell biology. In particular, we discuss energy metabolism in eukaryotic flagella, modifications to the canonical assembly pathway and flagellum function in parasite virulence. Protists The canonical ‘9+2’ microtubule axoneme is the prin- of inherited pathologies (or ciliopathies), including Eukaryotes that cannot be cipal feature of many motile cilia and flagella and is infertility, chronic respiratory disease, polycystic kid- classified as animals, fungi or one of the most iconic structures in cell biology. The ney disease and syndromes that include Bardet–Biedl, plants. The kingdom Protista origin of the eukaryotic flagellum and cilium is ancient Alstrom and Meckel syndrome6–12. Even illnesses such includes protozoa and algae. and predates the radiation, over 800 million years ago, as cancer, diabetes and obesity have been linked to cili- 1 6 Ciliates of the lineages that gave rise to extant eukaryotes . ary defects . The biological basis for some ciliopathies A ubiquitous group of protists, Therefore the absence of cilia and flagella from yeast, is undoubtedly defective sensing (an essential function members of which can be many fungi, red algae and higher plants are all examples provided by cilia), rather than defects in the assembly found in many wet of secondary loss. -
Ciliary Chemosensitivity Is Enhanced by Cilium Geometry and Motility
bioRxiv preprint doi: https://doi.org/10.1101/2021.01.13.425992; this version posted January 14, 2021. 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 4.0 International license. Ciliary chemosensitivity is enhanced by cilium geometry and motility David Hickey,1 Andrej Vilfan,1, 2, ∗ and Ramin Golestanian1, 3 1Max Planck Institute for Dynamics and Self-Organization (MPIDS), 37077 G¨ottingen,Germany 2JoˇzefStefan Institute, 1000 Ljubljana, Slovenia 3Rudolf Peierls Centre for Theoretical Physics, University of Oxford, Oxford OX1 3PU, United Kingdom (Dated: January 13, 2021) Cilia are hairlike organelles involved in both sensory functions and motility. We discuss the question of whether the location of chemical receptors on cilia provides an advantage in terms of sensitivity. Using a simple advection-diffusion model, we compute the capture rates of diffusive molecules on a cilium. Because of its geometry, a non-motile cilium in a quiescent fluid has a capture rate equivalent to a circular absorbing region with ∼ 4× its surface area. When the cilium is exposed to an external shear flow, the equivalent surface area increases to ∼ 10×. Alternatively, if the cilium beats in a non-reciprocal way, its capture rate increases with the beating frequency to the power of 1=3. Altogether, our results show that the protruding geometry of a cilium could be one of the reasons why so many receptors are located on cilia. They also point to the advantage of combining motility with chemical reception. -
Novel Interactions Between Phytoplankton and Microzooplankton: Their Influence on the Coupling Between Growth and Grazing Rates in the Sea
Hydrobiologia 480: 41–54, 2002. 41 C.E. Lee, S. Strom & J. Yen (eds), Progress in Zooplankton Biology: Ecology, Systematics, and Behavior. © 2002 Kluwer Academic Publishers. Printed in the Netherlands. Novel interactions between phytoplankton and microzooplankton: their influence on the coupling between growth and grazing rates in the sea Suzanne Strom Shannon Point Marine Center, Western Washington University, 1900 Shannon Point Rd., Anacortes, WA 98221, U.S.A. Tel: 360-293-2188. E-mail: [email protected] Key words: phytoplankton, microzooplankton, grazing, stability, behavior, evolution Abstract Understanding the processes that regulate phytoplankton biomass and growth rate remains one of the central issues for biological oceanography. While the role of resources in phytoplankton regulation (‘bottom up’ control) has been explored extensively, the role of grazing (‘top down’ control) is less well understood. This paper seeks to apply the approach pioneered by Frost and others, i.e. exploring consequences of individual grazer behavior for whole ecosystems, to questions about microzooplankton–phytoplankton interactions. Given the diversity and paucity of phytoplankton prey in much of the sea, there should be strong pressure for microzooplankton, the primary grazers of most phytoplankton, to evolve strategies that maximize prey encounter and utilization while allowing for survival in times of scarcity. These strategies include higher grazing rates on faster-growing phytoplankton cells, the direct use of light for enhancement of protist digestion rates, nutritional plasticity, rapid population growth combined with formation of resting stages, and defenses against predatory zooplankton. Most of these phenomena should increase community-level coupling (i.e. the degree of instantaneous and time-dependent similarity) between rates of phytoplankton growth and microzooplankton grazing, tending to stabilize planktonic ecosystems. -
28-Protistsf20r.Ppt [Compatibility Mode]
9/3/20 Ch 28: The Protists (a.k.a. Protoctists) (meet these in more detail in your book and lab) 1 Protists invent: eukaryotic cells size complexity Remember: 1°(primary) endosymbiosis? -> mitochondrion -> chloroplast genome unicellular -> multicellular 2 1 9/3/20 For chloroplasts 2° (secondary) happened (more complicated) {3°(tertiary) happened too} 3 4 Eukaryotic “supergroups” (SG; between K and P) 4 2 9/3/20 Protists invent sex: meiosis and fertilization -> 3 Life Cycles/Histories (Fig 13.6) Spores and some protists (Humans do this one) 5 “Algae” Group PS Pigments Euglenoids chl a & b (& carotenoids) Dinoflagellates chl a & c (usually) (& carotenoids) Diatoms chl a & c (& carotenoids) Xanthophytes chl a & c (& carotenoids) Chrysophytes chl a & c (& carotenoids) Coccolithophorids chl a & c (& carotenoids) Browns chl a & c (& carotenoids) Reds chl a, phycobilins (& carotenoids) Greens chl a & b (& carotenoids) (more groups exist) 6 3 9/3/20 Name word roots (indicate nutrition) “algae” (-phyt-) protozoa (no consistent word ending) “fungal-like” (-myc-) Ecological terms plankton phytoplankton zooplankton 7 SG: Excavata/Excavates “excavated” feeding groove some have reduced mitochondria (e.g.: mitosomes, hydrogenosomes) 8 4 9/3/20 SG: Excavata O: Diplomonads: †Giardia Cl: Parabasalids: Trichonympha (bk only) †Trichomonas P: Euglenophyta/zoa C: Kinetoplastids = trypanosomes/hemoflagellates: †Trypanosoma C: Euglenids: Euglena 9 SG: “SAR” clade: Clade Alveolates cell membrane 10 5 9/3/20 SG: “SAR” clade: Clade Alveolates P: Dinoflagellata/Pyrrophyta: -
The Macronuclear Genome of Stentor Coeruleus Reveals Tiny Introns in a Giant Cell
University of Pennsylvania ScholarlyCommons Departmental Papers (Biology) Department of Biology 2-20-2017 The Macronuclear Genome of Stentor coeruleus Reveals Tiny Introns in a Giant Cell Mark M. Slabodnick University of California, San Francisco J. G. Ruby University of California, San Francisco Sarah B. Reiff University of California, San Francisco Estienne C. Swart University of Bern Sager J. Gosai University of Pennsylvania See next page for additional authors Follow this and additional works at: https://repository.upenn.edu/biology_papers Recommended Citation Slabodnick, M. M., Ruby, J. G., Reiff, S. B., Swart, E. C., Gosai, S. J., Prabakaran, S., Witkowska, E., Larue, G. E., Gregory, B. D., Nowacki, M., Derisi, J., Roy, S. W., Marshall, W. F., & Sood, P. (2017). The Macronuclear Genome of Stentor coeruleus Reveals Tiny Introns in a Giant Cell. Current Biology, 27 (4), 569-575. http://dx.doi.org/10.1016/j.cub.2016.12.057 This paper is posted at ScholarlyCommons. https://repository.upenn.edu/biology_papers/49 For more information, please contact [email protected]. The Macronuclear Genome of Stentor coeruleus Reveals Tiny Introns in a Giant Cell Abstract The giant, single-celled organism Stentor coeruleus has a long history as a model system for studying pattern formation and regeneration in single cells. Stentor [1, 2] is a heterotrichous ciliate distantly related to familiar ciliate models, such as Tetrahymena or Paramecium. The primary distinguishing feature of Stentor is its incredible size: a single cell is 1 mm long. Early developmental biologists, including T.H. Morgan [3], were attracted to the system because of its regenerative abilities—if large portions of a cell are surgically removed, the remnant reorganizes into a normal-looking but smaller cell with correct proportionality [2, 3]. -
Number of Living Species in Australia and the World
Numbers of Living Species in Australia and the World 2nd edition Arthur D. Chapman Australian Biodiversity Information Services australia’s nature Toowoomba, Australia there is more still to be discovered… Report for the Australian Biological Resources Study Canberra, Australia September 2009 CONTENTS Foreword 1 Insecta (insects) 23 Plants 43 Viruses 59 Arachnida Magnoliophyta (flowering plants) 43 Protoctista (mainly Introduction 2 (spiders, scorpions, etc) 26 Gymnosperms (Coniferophyta, Protozoa—others included Executive Summary 6 Pycnogonida (sea spiders) 28 Cycadophyta, Gnetophyta under fungi, algae, Myriapoda and Ginkgophyta) 45 Chromista, etc) 60 Detailed discussion by Group 12 (millipedes, centipedes) 29 Ferns and Allies 46 Chordates 13 Acknowledgements 63 Crustacea (crabs, lobsters, etc) 31 Bryophyta Mammalia (mammals) 13 Onychophora (velvet worms) 32 (mosses, liverworts, hornworts) 47 References 66 Aves (birds) 14 Hexapoda (proturans, springtails) 33 Plant Algae (including green Reptilia (reptiles) 15 Mollusca (molluscs, shellfish) 34 algae, red algae, glaucophytes) 49 Amphibia (frogs, etc) 16 Annelida (segmented worms) 35 Fungi 51 Pisces (fishes including Nematoda Fungi (excluding taxa Chondrichthyes and (nematodes, roundworms) 36 treated under Chromista Osteichthyes) 17 and Protoctista) 51 Acanthocephala Agnatha (hagfish, (thorny-headed worms) 37 Lichen-forming fungi 53 lampreys, slime eels) 18 Platyhelminthes (flat worms) 38 Others 54 Cephalochordata (lancelets) 19 Cnidaria (jellyfish, Prokaryota (Bacteria Tunicata or Urochordata sea anenomes, corals) 39 [Monera] of previous report) 54 (sea squirts, doliolids, salps) 20 Porifera (sponges) 40 Cyanophyta (Cyanobacteria) 55 Invertebrates 21 Other Invertebrates 41 Chromista (including some Hemichordata (hemichordates) 21 species previously included Echinodermata (starfish, under either algae or fungi) 56 sea cucumbers, etc) 22 FOREWORD In Australia and around the world, biodiversity is under huge Harnessing core science and knowledge bases, like and growing pressure. -
An Evolutionary Switch in the Specificity of an Endosomal CORVET Tether Underlies
bioRxiv preprint doi: https://doi.org/10.1101/210328; this version posted October 27, 2017. 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. Title: An evolutionary switch in the specificity of an endosomal CORVET tether underlies formation of regulated secretory vesicles in the ciliate Tetrahymena thermophila Daniela Sparvolia, Elisabeth Richardsonb*, Hiroko Osakadac*, Xun Land,e*, Masaaki Iwamotoc, Grant R. Bowmana,f, Cassandra Kontura,g, William A. Bourlandh, Denis H. Lynni,j, Jonathan K. Pritchardd,e,k, Tokuko Haraguchic,l, Joel B. Dacksb, and Aaron P. Turkewitza th a Department of Molecular Genetics and Cell Biology, The University of Chicago, 920 E 58 Street, Chicago IL USA b Department of Cell Biology, University of Alberta, Canada c Advanced ICT Research Institute, National Institute of Information and Communications Technology (NICT), Kobe 651-2492, Japan. d Department of Genetics, Stanford University, Stanford, CA, 94305 e Howard Hughes Medical Institute, Stanford University, Stanford, CA 94305 f current affiliation: Department of Molecular Biology, University of Wyoming, Laramie g current affiliation: Department of Genetics, Yale University School of Medicine, New Haven, CT 06510 h Department of Biological Sciences, Boise State University, Boise ID 83725-1515 I Department of Integrative Biology, University of Guelph, Guelph ON N1G 2W1, Canada j current affiliation: Department of Zoology, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada k Department of Biology, Stanford University, Stanford, CA, 94305 l Graduate School of Frontier Biosciences, Osaka University, Suita 565-0871, Japan. -
The Intestinal Protozoa
The Intestinal Protozoa A. Introduction 1. The Phylum Protozoa is classified into four major subdivisions according to the methods of locomotion and reproduction. a. The amoebae (Superclass Sarcodina, Class Rhizopodea move by means of pseudopodia and reproduce exclusively by asexual binary division. b. The flagellates (Superclass Mastigophora, Class Zoomasitgophorea) typically move by long, whiplike flagella and reproduce by binary fission. c. The ciliates (Subphylum Ciliophora, Class Ciliata) are propelled by rows of cilia that beat with a synchronized wavelike motion. d. The sporozoans (Subphylum Sporozoa) lack specialized organelles of motility but have a unique type of life cycle, alternating between sexual and asexual reproductive cycles (alternation of generations). e. Number of species - there are about 45,000 protozoan species; around 8000 are parasitic, and around 25 species are important to humans. 2. Diagnosis - must learn to differentiate between the harmless and the medically important. This is most often based upon the morphology of respective organisms. 3. Transmission - mostly person-to-person, via fecal-oral route; fecally contaminated food or water important (organisms remain viable for around 30 days in cool moist environment with few bacteria; other means of transmission include sexual, insects, animals (zoonoses). B. Structures 1. trophozoite - the motile vegetative stage; multiplies via binary fission; colonizes host. 2. cyst - the inactive, non-motile, infective stage; survives the environment due to the presence of a cyst wall. 3. nuclear structure - important in the identification of organisms and species differentiation. 4. diagnostic features a. size - helpful in identifying organisms; must have calibrated objectives on the microscope in order to measure accurately. -
Amoebozoa) and Peatland Mosses
Old Lineages in a New Ecosystem: Diversification of Arcellinid Amoebae (Amoebozoa) and Peatland Mosses Omar Fiz-Palacios1*., Brian S. Leander2, Thierry J. Heger2. 1 Systematic Biology Program, Department of Organismal Biology, Evolutionary Biology Centre, Uppsala, Sweden, 2 Biodiversity Research Center, Departments of Zoology and Botany, University of British Columbia, Vancouver, BC, Canada Abstract Arcellinid testate amoebae (Amoebozoa) form a group of free-living microbial eukaryotes with one of the oldest fossil records known, yet several aspects of their evolutionary history remain poorly understood. Arcellinids occur in a range of terrestrial, freshwater and even brackish habitats; however, many arcellinid morphospecies such as Hyalosphenia papilio are particularly abundant in Sphagnum-dominated peatlands, a relatively new ecosystem that appeared during the diversification of Sphagnum species in the Miocene (5–20 Myr ago). Here, we reconstruct divergence times in arcellinid testate amoebae after selecting several fossils for clock calibrations and then infer whether or not arcellinids followed a pattern of diversification that parallels the pattern described for Sphagnum. We found that the diversification of core arcellinids occurred during the Phanerozoic, which is congruent with most arcellinid fossils but not with the oldest known amoebozoan fossil (i.e. at ca. 662 or ca. 750 Myr). Overall, Sphagnum and the Hyalospheniidae exhibit different patterns of diversification. However, an extensive molecular phylogenetic analysis of distinct clades within H. papilio species complex demonstrated a correlation between the recent diversification of H. papilio, the recent diversification of Sphagnum mosses, and the establishment of peatlands. Citation: Fiz-Palacios O, Leander BS, Heger TJ (2014) Old Lineages in a New Ecosystem: Diversification of Arcellinid Amoebae (Amoebozoa) and Peatland Mosses. -
A Revised Classification of Naked Lobose Amoebae (Amoebozoa
Protist, Vol. 162, 545–570, October 2011 http://www.elsevier.de/protis Published online date 28 July 2011 PROTIST NEWS A Revised Classification of Naked Lobose Amoebae (Amoebozoa: Lobosa) Introduction together constitute the amoebozoan subphy- lum Lobosa, which never have cilia or flagella, Molecular evidence and an associated reevaluation whereas Variosea (as here revised) together with of morphology have recently considerably revised Mycetozoa and Archamoebea are now grouped our views on relationships among the higher-level as the subphylum Conosa, whose constituent groups of amoebae. First of all, establishing the lineages either have cilia or flagella or have lost phylum Amoebozoa grouped all lobose amoe- them secondarily (Cavalier-Smith 1998, 2009). boid protists, whether naked or testate, aerobic Figure 1 is a schematic tree showing amoebozoan or anaerobic, with the Mycetozoa and Archamoe- relationships deduced from both morphology and bea (Cavalier-Smith 1998), and separated them DNA sequences. from both the heterolobosean amoebae (Page and The first attempt to construct a congruent molec- Blanton 1985), now belonging in the phylum Per- ular and morphological system of Amoebozoa by colozoa - Cavalier-Smith and Nikolaev (2008), and Cavalier-Smith et al. (2004) was limited by the the filose amoebae that belong in other phyla lack of molecular data for many amoeboid taxa, (notably Cercozoa: Bass et al. 2009a; Howe et al. which were therefore classified solely on morpho- 2011). logical evidence. Smirnov et al. (2005) suggested The phylum Amoebozoa consists of naked and another system for naked lobose amoebae only; testate lobose amoebae (e.g. Amoeba, Vannella, this left taxa with no molecular data incertae sedis, Hartmannella, Acanthamoeba, Arcella, Difflugia), which limited its utility.