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Busch A, Gerbracht JV, Davies K, Hoecker U, Hess S. Comparative transcriptomics elucidates the cellular responses of an aeroterrestrial zygnematophyte to UV radiation. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:3624-3642. [PMID: 38520340 PMCID: PMC11156808 DOI: 10.1093/jxb/erae131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Accepted: 03/22/2024] [Indexed: 03/25/2024]
Abstract
The zygnematophytes are the closest relatives of land plants and comprise several lineages that adapted to a life on land. Species of the genus Serritaenia form colorful, mucilaginous capsules, which surround the cells and block harmful solar radiation, one of the major terrestrial stressors. In eukaryotic algae, this 'sunscreen mucilage' represents a unique photoprotective strategy, whose induction and chemical background are unknown. We generated a de novo transcriptome of Serritaenia testaceovaginata and studied its gene regulation under moderate UV radiation (UVR) that triggers sunscreen mucilage under experimental conditions. UVR induced the repair of DNA and the photosynthetic apparatus as well as the synthesis of aromatic specialized metabolites. Specifically, we observed pronounced expressional changes in the production of aromatic amino acids, phenylpropanoid biosynthesis genes, potential cross-membrane transporters of phenolics, and extracellular, oxidative enzymes. Interestingly, the most up-regulated enzyme was a secreted class III peroxidase, whose embryophyte homologs are involved in apoplastic lignin formation. Overall, our findings reveal a conserved, plant-like UVR perception system (UVR8 and downstream factors) in zygnematophyte algae and point to a polyphenolic origin of the sunscreen pigment of Serritaenia, whose synthesis might be extracellular and oxidative, resembling that of plant lignins.
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Affiliation(s)
- Anna Busch
- Department of Biology, University of Cologne, Zülpicher Str. 47b, D-50674 Cologne, Germany
| | - Jennifer V Gerbracht
- Department of Biology, University of Cologne, Zülpicher Str. 47b, D-50674 Cologne, Germany
| | - Kevin Davies
- The New Zealand Institute for Plant and Food Research Limited, Private Bag 11600, Palmerston North 4442, New Zealand
| | - Ute Hoecker
- Institute for Plant Sciences and Cluster of Excellence on Plant Sciences (CEPLAS), Biocenter, University of Cologne, Zülpicher Strasse 47b, D-50674, Cologne, Germany
| | - Sebastian Hess
- Department of Biology, University of Cologne, Zülpicher Str. 47b, D-50674 Cologne, Germany
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Bowles AMC, Williams TA, Donoghue PCJ, Campbell DA, Williamson CJ. Metagenome-assembled genome of the glacier alga Ancylonema yields insights into the evolution of streptophyte life on ice and land. THE NEW PHYTOLOGIST 2024. [PMID: 38840553 DOI: 10.1111/nph.19860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2024] [Accepted: 05/03/2024] [Indexed: 06/07/2024]
Abstract
Contemporary glaciers are inhabited by streptophyte algae that balance photosynthesis and growth with tolerance of low temperature, desiccation and UV radiation. These same environmental challenges have been hypothesised as the driving force behind the evolution of land plants from streptophyte algal ancestors in the Cryogenian (720-635 million years ago). We sequenced, assembled and analysed the metagenome-assembled genome of the glacier alga Ancylonema nordenskiöldii to investigate its adaptations to life in ice, and whether this represents a vestige of Cryogenian exaptations. Phylogenetic analysis confirms the placement of glacier algae within the sister lineage to land plants, Zygnematophyceae. The metagenome-assembled genome is characterised by an expansion of genes involved in tolerance of high irradiance and UV light, while lineage-specific diversification is linked to the novel screening pigmentation of glacier algae. We found no support for the hypothesis of a common genomic basis for adaptations to ice and to land in streptophytes. Comparative genomics revealed that the reductive morphological evolution in the ancestor of Zygnematophyceae was accompanied by reductive genome evolution. This first genome-scale data for glacier algae suggests an Ancylonema-specific adaptation to the cryosphere, and sheds light on the genome evolution of land plants and Zygnematophyceae.
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Affiliation(s)
- Alexander M C Bowles
- School of Geographical Sciences, University of Bristol, University Road, Bristol, BS8 1SS, UK
- Bristol Palaeobiology Group, School of Biological Sciences and School of Earth Sciences, Life Sciences Building, University of Bristol, Bristol, BS8 1TQ, UK
| | - Tom A Williams
- Bristol Palaeobiology Group, School of Biological Sciences and School of Earth Sciences, Life Sciences Building, University of Bristol, Bristol, BS8 1TQ, UK
| | - Philip C J Donoghue
- Bristol Palaeobiology Group, School of Biological Sciences and School of Earth Sciences, Life Sciences Building, University of Bristol, Bristol, BS8 1TQ, UK
| | - Douglas A Campbell
- Department of Biology, Mount Allison University, Sackville, NB, E4L 1H3, Canada
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3
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Domozych DS, LoRicco JG. The extracellular matrix of green algae. PLANT PHYSIOLOGY 2023; 194:15-32. [PMID: 37399237 PMCID: PMC10762512 DOI: 10.1093/plphys/kiad384] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 05/25/2023] [Accepted: 05/30/2023] [Indexed: 07/05/2023]
Abstract
Green algae display a wide range of extracellular matrix (ECM) components that include various types of cell walls (CW), scales, crystalline glycoprotein coverings, hydrophobic compounds, and complex gels or mucilage. Recently, new information derived from genomic/transcriptomic screening, advanced biochemical analyses, immunocytochemical studies, and ecophysiology has significantly enhanced and refined our understanding of the green algal ECM. In the later diverging charophyte group of green algae, the CW and other ECM components provide insight into the evolution of plants and the ways the ECM modulates during environmental stress. Chlorophytes produce diverse ECM components, many of which have been exploited for various uses in medicine, food, and biofuel production. This review highlights major advances in ECM studies of green algae.
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Affiliation(s)
- David S Domozych
- Department of Biology, Skidmore College, Saratoga Springs, NY 12866, USA
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4
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Feng X, Zheng J, Irisarri I, Yu H, Zheng B, Ali Z, de Vries S, Keller J, Fürst-Jansen JM, Dadras A, Zegers JM, Rieseberg TP, Ashok AD, Darienko T, Bierenbroodspot MJ, Gramzow L, Petroll R, Haas FB, Fernandez-Pozo N, Nousias O, Li T, Fitzek E, Grayburn WS, Rittmeier N, Permann C, Rümpler F, Archibald JM, Theißen G, Mower JP, Lorenz M, Buschmann H, von Schwartzenberg K, Boston L, Hayes RD, Daum C, Barry K, Grigoriev IV, Wang X, Li FW, Rensing SA, Ari JB, Keren N, Mosquna A, Holzinger A, Delaux PM, Zhang C, Huang J, Mutwil M, de Vries J, Yin Y. Chromosome-level genomes of multicellular algal sisters to land plants illuminate signaling network evolution. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.31.526407. [PMID: 36778228 PMCID: PMC9915684 DOI: 10.1101/2023.01.31.526407] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The filamentous and unicellular algae of the class Zygnematophyceae are the closest algal relatives of land plants. Inferring the properties of the last common ancestor shared by these algae and land plants allows us to identify decisive traits that enabled the conquest of land by plants. We sequenced four genomes of filamentous Zygnematophyceae (three strains of Zygnema circumcarinatum and one strain of Z. cylindricum) and generated chromosome-scale assemblies for all strains of the emerging model system Z. circumcarinatum. Comparative genomic analyses reveal expanded genes for signaling cascades, environmental response, and intracellular trafficking that we associate with multicellularity. Gene family analyses suggest that Zygnematophyceae share all the major enzymes with land plants for cell wall polysaccharide synthesis, degradation, and modifications; most of the enzymes for cell wall innovations, especially for polysaccharide backbone synthesis, were gained more than 700 million years ago. In Zygnematophyceae, these enzyme families expanded, forming co-expressed modules. Transcriptomic profiling of over 19 growth conditions combined with co-expression network analyses uncover cohorts of genes that unite environmental signaling with multicellular developmental programs. Our data shed light on a molecular chassis that balances environmental response and growth modulation across more than 600 million years of streptophyte evolution.
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Affiliation(s)
- Xuehuan Feng
- University of Nebraska-Lincoln, Department of Food Science and Technology, Lincoln, NE 68588, USA
| | - Jinfang Zheng
- University of Nebraska-Lincoln, Department of Food Science and Technology, Lincoln, NE 68588, USA
| | - Iker Irisarri
- University of Goettingen, Institute of Microbiology and Genetics, Department of Applied Bioinformatics, Goldschmidtstr. 1, 37077 Goettingen, Germany
- University of Goettingen, Campus Institute Data Science (CIDAS), Goldschmidstr. 1, 37077 Goettingen, Germany
- Section Phylogenomics, Centre for Molecular biodiversity Research, Leibniz Institute for the Analysis of Biodiversity Change (LIB), Zoological Museum Hamburg, Martin-Luther-King-Platz 3, 20146 Hamburg, Germany
| | - Huihui Yu
- University of Nebraska-Lincoln, Center for Plant Science Innovation, Lincoln, NE 68588, USA
| | - Bo Zheng
- University of Nebraska-Lincoln, Department of Food Science and Technology, Lincoln, NE 68588, USA
| | - Zahin Ali
- Nanyang Technological University, School of Biological Sciences, 60 Nanyang Drive, Singapore 637551, Singapore
| | - Sophie de Vries
- University of Goettingen, Institute of Microbiology and Genetics, Department of Applied Bioinformatics, Goldschmidtstr. 1, 37077 Goettingen, Germany
| | - Jean Keller
- Laboratoire de Recherche en Sciences Végétales (LRSV), Université de Toulouse, CNRS, UPS, INP Toulouse, Castanet-Tolosan, 31326, France
| | - Janine M.R. Fürst-Jansen
- University of Goettingen, Institute of Microbiology and Genetics, Department of Applied Bioinformatics, Goldschmidtstr. 1, 37077 Goettingen, Germany
| | - Armin Dadras
- University of Goettingen, Institute of Microbiology and Genetics, Department of Applied Bioinformatics, Goldschmidtstr. 1, 37077 Goettingen, Germany
| | - Jaccoline M.S. Zegers
- University of Goettingen, Institute of Microbiology and Genetics, Department of Applied Bioinformatics, Goldschmidtstr. 1, 37077 Goettingen, Germany
| | - Tim P. Rieseberg
- University of Goettingen, Institute of Microbiology and Genetics, Department of Applied Bioinformatics, Goldschmidtstr. 1, 37077 Goettingen, Germany
| | - Amra Dhabalia Ashok
- University of Goettingen, Institute of Microbiology and Genetics, Department of Applied Bioinformatics, Goldschmidtstr. 1, 37077 Goettingen, Germany
| | - Tatyana Darienko
- University of Goettingen, Institute of Microbiology and Genetics, Department of Applied Bioinformatics, Goldschmidtstr. 1, 37077 Goettingen, Germany
| | - Maaike J. Bierenbroodspot
- University of Goettingen, Institute of Microbiology and Genetics, Department of Applied Bioinformatics, Goldschmidtstr. 1, 37077 Goettingen, Germany
| | - Lydia Gramzow
- University of Jena, Matthias Schleiden Institute / Genetics, 07743, Jena, Germany
| | - Romy Petroll
- Plant Cell Biology, Department of Biology, University of Marburg, Marburg, Germany
- Department of Algal Development and Evolution, Max Planck Institute for Biology Tübingen, Tübingen, Germany
| | - Fabian B. Haas
- Plant Cell Biology, Department of Biology, University of Marburg, Marburg, Germany
- Department of Algal Development and Evolution, Max Planck Institute for Biology Tübingen, Tübingen, Germany
| | - Noe Fernandez-Pozo
- Plant Cell Biology, Department of Biology, University of Marburg, Marburg, Germany
- Institute for Mediterranean and Subtropical Horticulture “La Mayora” (UMA-CSIC)
| | - Orestis Nousias
- University of Nebraska-Lincoln, Department of Food Science and Technology, Lincoln, NE 68588, USA
| | - Tang Li
- University of Nebraska-Lincoln, Department of Food Science and Technology, Lincoln, NE 68588, USA
| | - Elisabeth Fitzek
- Computational Biology, Department of Biology, Center for Biotechnology, Bielefeld University, Bielefeld, Germany
| | - W. Scott Grayburn
- Northern Illinois University, Molecular Core Lab, Department of Biological Sciences, DeKalb, IL 60115, USA
| | - Nina Rittmeier
- University of Innsbruck, Department of Botany, Research Group Plant Cell Biology, Sternwartestraße 15, A-6020 Innsbruck, Austria
| | - Charlotte Permann
- University of Innsbruck, Department of Botany, Research Group Plant Cell Biology, Sternwartestraße 15, A-6020 Innsbruck, Austria
| | - Florian Rümpler
- University of Jena, Matthias Schleiden Institute / Genetics, 07743, Jena, Germany
| | - John M. Archibald
- Dalhousie University, Department of Biochemistry and Molecular Biology, 5850 College Street, Halifax NS B3H 4R2, Canada
| | - Günter Theißen
- University of Jena, Matthias Schleiden Institute / Genetics, 07743, Jena, Germany
| | - Jeffrey P. Mower
- University of Nebraska-Lincoln, Center for Plant Science Innovation, Lincoln, NE 68588, USA
| | - Maike Lorenz
- University of Goettingen, Albrecht-von-Haller-Institute for Plant Sciences, Experimental Phycology and Culture Collection of Algae at Goettingen University (EPSAG), Nikolausberger Weg 18, 37073 Goettingen, Germany
| | - Henrik Buschmann
- University of Applied Sciences Mittweida, Faculty of Applied Computer Sciences and Biosciences, Section Biotechnology and Chemistry, Molecular Biotechnology, Technikumplatz 17, 09648 Mittweida, Germany
| | - Klaus von Schwartzenberg
- Universität Hamburg, Institute of Plant Science and Microbiology, Microalgae and Zygnematophyceae Collection Hamburg (MZCH) and Aquatic Ecophysiology and Phycology, Ohnhorststr. 18, 22609, Hamburg, Germany
| | - Lori Boston
- Genome Sequencing Center, HudsonAlpha Institute for Biotechnology, Huntsville, AL, USA
| | - Richard D. Hayes
- Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Chris Daum
- Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Kerrie Barry
- Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Igor V. Grigoriev
- Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- Department of Plant and Microbial Biology, University of California Berkeley, Berkeley, CA 94720, USA
| | - Xiyin Wang
- North China University of Science and Technology
| | - Fay-Wei Li
- Boyce Thompson Institute, Ithaca, NY, USA
- Cornell University, Plant Biology Section, Ithaca, NY, USA
| | - Stefan A. Rensing
- Plant Cell Biology, Department of Biology, University of Marburg, Marburg, Germany
- University of Freiburg, Centre for Biological Signalling Studies (BIOSS), Freiburg, Germany
| | - Julius Ben Ari
- The Hebrew University of Jerusalem, The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, Rehovot 7610000, Israel
| | - Noa Keren
- The Hebrew University of Jerusalem, The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, Rehovot 7610000, Israel
| | - Assaf Mosquna
- The Hebrew University of Jerusalem, The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, Rehovot 7610000, Israel
| | - Andreas Holzinger
- University of Innsbruck, Department of Botany, Research Group Plant Cell Biology, Sternwartestraße 15, A-6020 Innsbruck, Austria
| | - Pierre-Marc Delaux
- Laboratoire de Recherche en Sciences Végétales (LRSV), Université de Toulouse, CNRS, UPS, INP Toulouse, Castanet-Tolosan, 31326, France
| | - Chi Zhang
- University of Nebraska-Lincoln, Center for Plant Science Innovation, Lincoln, NE 68588, USA
- University of Nebraska-Lincoln, School of Biological Sciences, Lincoln, NE 68588, USA
| | - Jinling Huang
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, China
- Department of Biology, East Carolina University, Greenville, NC, USA
| | - Marek Mutwil
- Nanyang Technological University, School of Biological Sciences, 60 Nanyang Drive, Singapore 637551, Singapore
| | - Jan de Vries
- University of Goettingen, Institute of Microbiology and Genetics, Department of Applied Bioinformatics, Goldschmidtstr. 1, 37077 Goettingen, Germany
- University of Goettingen, Campus Institute Data Science (CIDAS), Goldschmidstr. 1, 37077 Goettingen, Germany
- University of Goettingen, Goettingen Center for Molecular Biosciences (GZMB), Justus-von-Liebig-Weg 11, 37077 Goettingen, Germany
| | - Yanbin Yin
- University of Nebraska-Lincoln, Department of Food Science and Technology, Lincoln, NE 68588, USA
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5
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Rieseberg TP, Dadras A, Fürst-Jansen JMR, Dhabalia Ashok A, Darienko T, de Vries S, Irisarri I, de Vries J. Crossroads in the evolution of plant specialized metabolism. Semin Cell Dev Biol 2023; 134:37-58. [PMID: 35292191 DOI: 10.1016/j.semcdb.2022.03.004] [Citation(s) in RCA: 27] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 02/17/2022] [Accepted: 03/04/2022] [Indexed: 12/25/2022]
Abstract
The monophyletic group of embryophytes (land plants) stands out among photosynthetic eukaryotes: they are the sole constituents of the macroscopic flora on land. In their entirety, embryophytes account for the majority of the biomass on land and constitute an astounding biodiversity. What allowed for the massive radiation of this particular lineage? One of the defining features of all land plants is the production of an array of specialized metabolites. The compounds that the specialized metabolic pathways of embryophytes produce have diverse functions, ranging from superabundant structural polymers and compounds that ward off abiotic and biotic challenges, to signaling molecules whose abundance is measured at the nanomolar scale. These specialized metabolites govern the growth, development, and physiology of land plants-including their response to the environment. Hence, specialized metabolites define the biology of land plants as we know it. And they were likely a foundation for their success. It is thus intriguing to find that the closest algal relatives of land plants, freshwater organisms from the grade of streptophyte algae, possess homologs for key enzymes of specialized metabolic pathways known from land plants. Indeed, some studies suggest that signature metabolites emerging from these pathways can be found in streptophyte algae. Here we synthesize the current understanding of which routes of the specialized metabolism of embryophytes can be traced to a time before plants had conquered land.
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Affiliation(s)
- Tim P Rieseberg
- University of Goettingen, Institute for Microbiology and Genetics, Department of Applied Bioinformatics, Goldschmidtstr. 1, 37077 Goettingen, Germany
| | - Armin Dadras
- University of Goettingen, Institute for Microbiology and Genetics, Department of Applied Bioinformatics, Goldschmidtstr. 1, 37077 Goettingen, Germany
| | - Janine M R Fürst-Jansen
- University of Goettingen, Institute for Microbiology and Genetics, Department of Applied Bioinformatics, Goldschmidtstr. 1, 37077 Goettingen, Germany
| | - Amra Dhabalia Ashok
- University of Goettingen, Institute for Microbiology and Genetics, Department of Applied Bioinformatics, Goldschmidtstr. 1, 37077 Goettingen, Germany
| | - Tatyana Darienko
- University of Goettingen, Institute for Microbiology and Genetics, Department of Applied Bioinformatics, Goldschmidtstr. 1, 37077 Goettingen, Germany
| | - Sophie de Vries
- University of Goettingen, Institute for Microbiology and Genetics, Department of Applied Bioinformatics, Goldschmidtstr. 1, 37077 Goettingen, Germany
| | - Iker Irisarri
- University of Goettingen, Institute for Microbiology and Genetics, Department of Applied Bioinformatics, Goldschmidtstr. 1, 37077 Goettingen, Germany; University of Goettingen, Campus Institute Data Science (CIDAS), Goldschmidstr. 1, 37077 Goettingen, Germany
| | - Jan de Vries
- University of Goettingen, Institute for Microbiology and Genetics, Department of Applied Bioinformatics, Goldschmidtstr. 1, 37077 Goettingen, Germany; University of Goettingen, Campus Institute Data Science (CIDAS), Goldschmidstr. 1, 37077 Goettingen, Germany; University of Goettingen, Goettingen Center for Molecular Biosciences (GZMB), Department of Applied Bioinformatics, Goldschmidtsr. 1, 37077 Goettingen, Germany.
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6
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Davies KM, Landi M, van Klink JW, Schwinn KE, Brummell DA, Albert NW, Chagné D, Jibran R, Kulshrestha S, Zhou Y, Bowman JL. Evolution and function of red pigmentation in land plants. ANNALS OF BOTANY 2022; 130:613-636. [PMID: 36070407 PMCID: PMC9670752 DOI: 10.1093/aob/mcac109] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2022] [Accepted: 09/05/2022] [Indexed: 05/10/2023]
Abstract
BACKGROUND Land plants commonly produce red pigmentation as a response to environmental stressors, both abiotic and biotic. The type of pigment produced varies among different land plant lineages. In the majority of species they are flavonoids, a large branch of the phenylpropanoid pathway. Flavonoids that can confer red colours include 3-hydroxyanthocyanins, 3-deoxyanthocyanins, sphagnorubins and auronidins, which are the predominant red pigments in flowering plants, ferns, mosses and liverworts, respectively. However, some flowering plants have lost the capacity for anthocyanin biosynthesis and produce nitrogen-containing betalain pigments instead. Some terrestrial algal species also produce red pigmentation as an abiotic stress response, and these include both carotenoid and phenolic pigments. SCOPE In this review, we examine: which environmental triggers induce red pigmentation in non-reproductive tissues; theories on the functions of stress-induced pigmentation; the evolution of the biosynthetic pathways; and structure-function aspects of different pigment types. We also compare data on stress-induced pigmentation in land plants with those for terrestrial algae, and discuss possible explanations for the lack of red pigmentation in the hornwort lineage of land plants. CONCLUSIONS The evidence suggests that pigment biosynthetic pathways have evolved numerous times in land plants to provide compounds that have red colour to screen damaging photosynthetically active radiation but that also have secondary functions that provide specific benefits to the particular land plant lineage.
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Affiliation(s)
| | - Marco Landi
- Department of Agriculture, Food and Environment, University of Pisa, Italy
| | - John W van Klink
- The New Zealand Institute for Plant and Food Research Limited, Department of Chemistry, Otago University, Dunedin, New Zealand
| | - Kathy E Schwinn
- The New Zealand Institute for Plant and Food Research Limited, Private Bag 11600, Palmerston North 4442, New Zealand
| | - David A Brummell
- The New Zealand Institute for Plant and Food Research Limited, Private Bag 11600, Palmerston North 4442, New Zealand
| | - Nick W Albert
- The New Zealand Institute for Plant and Food Research Limited, Private Bag 11600, Palmerston North 4442, New Zealand
| | - David Chagné
- The New Zealand Institute for Plant and Food Research Limited, Private Bag 11600, Palmerston North 4442, New Zealand
| | - Rubina Jibran
- The New Zealand Institute for Plant and Food Research Limited, Private Bag 92169, Auckland Mail Centre, Auckland 1142, New Zealand
| | - Samarth Kulshrestha
- The New Zealand Institute for Plant and Food Research Limited, Private Bag 11600, Palmerston North 4442, New Zealand
| | - Yanfei Zhou
- The New Zealand Institute for Plant and Food Research Limited, Private Bag 11600, Palmerston North 4442, New Zealand
| | - John L Bowman
- School of Biological Sciences, Monash University, Melbourne, VIC, Australia
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7
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Domozych DS, Bagdan K. The cell biology of charophytes: Exploring the past and models for the future. PLANT PHYSIOLOGY 2022; 190:1588-1608. [PMID: 35993883 PMCID: PMC9614468 DOI: 10.1093/plphys/kiac390] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 07/26/2022] [Indexed: 06/15/2023]
Abstract
Charophytes (Streptophyta) represent a diverse assemblage of extant green algae that are the sister lineage to land plants. About 500-600+ million years ago, a charophyte progenitor successfully colonized land and subsequently gave rise to land plants. Charophytes have diverse but relatively simple body plans that make them highly attractive organisms for many areas of biological research. At the cellular level, many charophytes have been used for deciphering cytoskeletal networks and their dynamics, membrane trafficking, extracellular matrix secretion, and cell division mechanisms. Some charophytes live in challenging habitats and have become excellent models for elucidating the cellular and molecular effects of various abiotic stressors on plant cells. Recent sequencing of several charophyte genomes has also opened doors for the dissection of biosynthetic and signaling pathways. While we are only in an infancy stage of elucidating the cell biology of charophytes, the future application of novel analytical methodologies in charophyte studies that include a broader survey of inclusive taxa will enhance our understanding of plant evolution and cell dynamics.
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Affiliation(s)
| | - Kaylee Bagdan
- Department of Biology, Skidmore Microscopy Imaging Center, Skidmore College, Saratoga Springs, New York 12866, USA
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8
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Hess S, Williams SK, Busch A, Irisarri I, Delwiche CF, de Vries S, Darienko T, Roger AJ, Archibald JM, Buschmann H, von Schwartzenberg K, de Vries J. A phylogenomically informed five-order system for the closest relatives of land plants. Curr Biol 2022; 32:4473-4482.e7. [PMID: 36055238 PMCID: PMC9632326 DOI: 10.1016/j.cub.2022.08.022] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 08/01/2022] [Accepted: 08/10/2022] [Indexed: 12/15/2022]
Abstract
The evolution of streptophytes had a profound impact on life on Earth. They brought forth those photosynthetic eukaryotes that today dominate the macroscopic flora: the land plants (Embryophyta).1 There is convincing evidence that the unicellular/filamentous Zygnematophyceae-and not the morphologically more elaborate Coleochaetophyceae or Charophyceae-are the closest algal relatives of land plants.2-6 Despite the species richness (>4,000), wide distribution, and key evolutionary position of the zygnematophytes, their internal phylogeny remains largely unresolved.7,8 There are also putative zygnematophytes with interesting body plan modifications (e.g., filamentous growth) whose phylogenetic affiliations remain unknown. Here, we studied a filamentous green alga (strain MZCH580) from an Austrian peat bog with central or parietal chloroplasts that lack discernible pyrenoids. It represents Mougeotiopsis calospora PALLA, an enigmatic alga that was described more than 120 years ago9 but never subjected to molecular analyses. We generated transcriptomic data of M. calospora strain MZCH580 and conducted comprehensive phylogenomic analyses (326 nuclear loci) for 46 taxonomically diverse zygnematophytes. Strain MZCH580 falls in a deep-branching zygnematophycean clade together with some unicellular species and thus represents a formerly unknown zygnematophycean lineage with filamentous growth. Our well-supported phylogenomic tree lets us propose a new five-order system for the Zygnematophyceae and provides evidence for at least five independent origins of true filamentous growth in the closest algal relatives of land plants. This phylogeny provides a robust and comprehensive framework for performing comparative analyses and inferring the evolution of cellular traits and body plans in the closest relatives of land plants.
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Affiliation(s)
- Sebastian Hess
- Institute for Zoology, University of Cologne, Zülpicher Str. 47b, 50674 Cologne, Germany.
| | - Shelby K Williams
- Department of Biochemistry and Molecular Biology, Dalhousie University, 5850 College St., Halifax NS B3H 4R2, Canada
| | - Anna Busch
- Institute for Zoology, University of Cologne, Zülpicher Str. 47b, 50674 Cologne, Germany
| | - Iker Irisarri
- University of Goettingen, Institute for Microbiology and Genetics, Department of Applied Bioinformatics, Goldschmidtstr. 1, 37077 Goettingen, Germany; University of Goettingen, Campus Institute Data Science (CIDAS), Goldschmidstr. 1, 37077 Goettingen, Germany
| | - Charles F Delwiche
- Cell Biology and Molecular Genetics, University of Maryland-College Park, College Park, MD, USA
| | - Sophie de Vries
- University of Goettingen, Institute for Microbiology and Genetics, Department of Applied Bioinformatics, Goldschmidtstr. 1, 37077 Goettingen, Germany
| | - Tatyana Darienko
- University of Goettingen, Institute for Microbiology and Genetics, Department of Applied Bioinformatics, Goldschmidtstr. 1, 37077 Goettingen, Germany
| | - Andrew J Roger
- Department of Biochemistry and Molecular Biology, Dalhousie University, 5850 College St., Halifax NS B3H 4R2, Canada
| | - John M Archibald
- Department of Biochemistry and Molecular Biology, Dalhousie University, 5850 College St., Halifax NS B3H 4R2, Canada
| | - Henrik Buschmann
- University of Applied Sciences Mittweida, Faculty of Applied Computer Sciences and Biosciences, Section Biotechnology and Chemistry, Molecular Biotechnology, Technikumplatz 17, 09648 Mittweida, Germany
| | - Klaus von Schwartzenberg
- Universität Hamburg, Institute of Plant Science and Microbiology, Microalgae and Zygnematophyceae Collection Hamburg (MZCH) and Aquatic Ecophysiology and Phycology, Ohnhorststr. 18, 22609 Hamburg, Germany
| | - Jan de Vries
- University of Goettingen, Institute for Microbiology and Genetics, Department of Applied Bioinformatics, Goldschmidtstr. 1, 37077 Goettingen, Germany; University of Goettingen, Campus Institute Data Science (CIDAS), Goldschmidstr. 1, 37077 Goettingen, Germany; University of Goettingen, Goettingen Center for Molecular Biosciences (GZMB), Department of Applied Bioinformatics, Goldschmidtstr. 1, 37077 Goettingen, Germany.
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9
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Pigment signatures of algal communities and their implications for glacier surface darkening. Sci Rep 2022; 12:17643. [PMID: 36271236 PMCID: PMC9587043 DOI: 10.1038/s41598-022-22271-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 10/12/2022] [Indexed: 01/18/2023] Open
Abstract
Blooms of pigmented algae darken the surface of glaciers and ice sheets, thereby enhancing solar energy absorption and amplifying ice and snow melt. The impacts of algal pigment and community composition on surface darkening are still poorly understood. Here, we characterise glacier ice and snow algal pigment signatures on snow and bare ice surfaces and study their role in photophysiology and energy absorption on three glaciers in Southeast Greenland. Purpurogallin and astaxanthin esters dominated the glacier ice and snow algal pigment pools (mass ratios to chlorophyll a of 32 and 56, respectively). Algal biomass and pigments impacted chromophoric dissolved organic matter concentrations. Despite the effective absorption of astaxanthin esters at wavelengths where incoming irradiance peaks, the cellular energy absorption of snow algae was 95% lower than anticipated from their pigmentation, due to pigment packaging. The energy absorption of glacier ice algae was consequently ~ 5 × higher. On bare ice, snow algae may have locally contributed up to 13% to total biological radiative forcing, despite contributing 44% to total biomass. Our results give new insights into the impact of algal community composition on bare ice energy absorption and biomass accumulation during snow melt.
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10
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Trumhová K, Klimešová V, Pichrtová M. Seasonal Dynamics of Zygnema (Zygnematophyceae) Mats from the Austrian Alps. MICROBIAL ECOLOGY 2022:10.1007/s00248-022-02105-6. [PMID: 36053304 DOI: 10.1007/s00248-022-02105-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 08/24/2022] [Indexed: 06/15/2023]
Abstract
Filamentous green algae of the genus Zygnema are an essential part of hydro-terrestrial ecosystems. Despite several studies on their resistance to natural stresses, little is known about the composition of their assemblages and the changes they undergo over time. Two sites at altitudes above 2200 m a.s.l. in the Austrian Alps were selected for a 2-year observation period and sampled five times. Molecular phylogenetic analysis of the 152 isolated strains of Zygnema sp. was performed based on the rbcL and trnG sequences. Seven genotypes were found at these sites during the samplings, but their proportion varied throughout the seasons. The site with a more stable water regime also had a more stable representation of genotypes, in contrast to the site with fluctuating water availability. The mats formed resistant pre-akinetes at the end of the season with reduced photosynthetic activity. Contrary to expectations, the mats were not exposed to extremely cold temperatures in winter due to snow cover. Some genotypes have been previously observed at this site, indicating that the population composition is stable. This work highlights the importance of resistant pre-akinetes in surviving winter conditions, the ability of algae to re-establish mats, and the need to address the hidden diversity of the genus Zygnema.
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Affiliation(s)
- Kateřina Trumhová
- Faculty of Science, Department of Botany, Charles University, Benátská 2, 128 00, Prague, Czech Republic.
| | - Vanda Klimešová
- Institute of Criminalistics Prague, Strojnická 27, 170 89, Prague, Czech Republic
| | - Martina Pichrtová
- Faculty of Science, Department of Botany, Charles University, Benátská 2, 128 00, Prague, Czech Republic
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11
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Permann C, Becker B, Holzinger A. Temperature- and light stress adaptations in Zygnematophyceae: The challenges of a semi-terrestrial lifestyle. FRONTIERS IN PLANT SCIENCE 2022; 13:945394. [PMID: 35928713 PMCID: PMC9343959 DOI: 10.3389/fpls.2022.945394] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 06/29/2022] [Indexed: 06/15/2023]
Abstract
Streptophyte green algae comprise the origin of land plants and therefore life on earth as we know it today. While terrestrialization opened new habitats, leaving the aquatic environment brought additional abiotic stresses. More-drastic temperature shifts and high light levels are major abiotic stresses in semi-terrestrial habitats, in addition to desiccation, which has been reviewed elsewhere. Zygnematophyceae, a species-rich class of streptophyte green algae, is considered a sister-group to embryophytes. They have developed a variety of avoidance and adaptation mechanisms to protect against temperature extremes and high radiation in the form of photosynthetically active and ultraviolet radiation (UV) radiation occurring on land. Recently, knowledge of transcriptomic and metabolomic changes as consequences of these stresses has become available. Land-plant stress-signaling pathways producing homologs of key enzymes have been described in Zygnematophyceae. An efficient adaptation strategy is their mat-like growth habit, which provides self-shading and protects lower layers from harmful radiation. Additionally, Zygnematophyceae possess phenolic compounds with UV-screening ability. Resting stages such as vegetative pre-akinetes tolerate freezing to a much higher extent than do young cells. Sexual reproduction occurs by conjugation without the formation of flagellated male gametes, which can be seen as an advantage in water-deficient habitats. The resulting zygospores possess a multilayer cell wall, contributing to their resistance to terrestrial conditions. Especially in the context of global change, understanding temperature and light tolerance is crucial.
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Affiliation(s)
- Charlotte Permann
- Department of Botany, Functional Plant Biology, University of Innsbruck, Innsbruck, Austria
| | - Burkhard Becker
- Department of Biology, Institute for Plant Sciences, University of Cologne, Cologne, Germany
| | - Andreas Holzinger
- Department of Botany, Functional Plant Biology, University of Innsbruck, Innsbruck, Austria
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12
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Oliveira MF, Maciel-Silva AS. Biological soil crusts and how they might colonize other worlds: insights from these Brazilian ecosystem engineers. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:4362-4379. [PMID: 35522077 DOI: 10.1093/jxb/erac162] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 04/17/2022] [Indexed: 06/14/2023]
Abstract
When bryophytes, lichens, eukaryotic algae, cyanobacteria, bacteria, and fungi live interacting intimately with the most superficial particles of the soil, they form a complex community of organisms called the biological soil crust (BSC or biocrust). These biocrusts occur predominantly in drylands, where they provide important ecological services such as soil aggregation, moisture retention, and nitrogen fixation. Unfortunately, many BSC communities remain poorly explored, especially in the tropics. This review summarizes studies about BSCs in Brazil, a tropical megadiverse country, and shows the importance of ecological, physiological, and taxonomic knowledge of biocrusts. We also compare Brazilian BSC communities with others around the world, describe why BSCs can be considered ecosystem engineers, and propose their use in the colonization of other worlds.
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Affiliation(s)
- Mateus Fernandes Oliveira
- Universidade Federal de Minas Gerais, Laboratório de Sistemática Vegetal, Departamento de Botânica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Pampulha, Belo Horizonte, MG, 31270-901, Brazil
| | - Adaíses Simone Maciel-Silva
- Universidade Federal de Minas Gerais, Laboratório de Sistemática Vegetal, Departamento de Botânica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Pampulha, Belo Horizonte, MG, 31270-901, Brazil
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13
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Del Mondo A, Sansone C, Brunet C. Insights into the biosynthesis pathway of phenolic compounds in microalgae. Comput Struct Biotechnol J 2022; 20:1901-1913. [PMID: 35521550 PMCID: PMC9052079 DOI: 10.1016/j.csbj.2022.04.019] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 04/04/2022] [Accepted: 04/14/2022] [Indexed: 01/18/2023] Open
Abstract
Microalgal PCs are important bioactive molecules beneficial for human health. Bioinformatic comparative exploration predicts PCs synthesis in microalgae. Ten groups of prokaryotic and eukaryotic microalgae reveal a conserved pathway core. Featured PCs can be restricted to diverse microalgae due to ecological implications.
Among the most relevant bioactive molecules family, phenolic compounds (PCs) are well known in higher plants, while their knowledge in microalgae is still scarce. Microalgae represent a novel and promising source of human health benefit compounds to be involved, for instance, in nutraceutical composition. This study aims to investigate the PCs biosynthetic pathway in the microalgal realm, exploring its potential variability over the microalgal biodiversity axis. A multistep in silico analysis was carried out using a selection of core enzymes from the pathway described in land plants. This study explores their presence in ten groups of prokaryotic and eukaryotic microalgae.. Analyses were carried out taking into account a wide selection of algal protein homologs, functional annotation of conserved domains and motifs, and maximum-likelihood tree construction. Results showed that a conserved core of the pathway for PCs biosynthesis is shared horizontally in all microalgae. Conversely, the ability to synthesize some subclasses of phenolics may be restricted to only some microalgal groups (i.e., Chlorophyta) depending on featured enzymes, such as the flavanone naringenin and other related chalcone isomerase dependent compounds.
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Affiliation(s)
- Angelo Del Mondo
- Stazione zoologica Anton Dohrn, sede Molosiglio Marina Acton, via ammiraglio F. Acton, 55., 80133 Napoli, Italy
- Corresponding author.
| | - Clementina Sansone
- Stazione zoologica Anton Dohrn, sede Molosiglio Marina Acton, via ammiraglio F. Acton, 55., 80133 Napoli, Italy
- Institute of Biomolecular Chemistry, CNR, via Campi Flegrei 34, Pozzuoli 80078, Na, Italy
| | - Christophe Brunet
- Stazione zoologica Anton Dohrn, sede Molosiglio Marina Acton, via ammiraglio F. Acton, 55., 80133 Napoli, Italy
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14
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Kapoor S, Singh M, Srivastava A, Chavali M, Chandrasekhar K, Verma P. Extraction and characterization of microalgae-derived phenolics for pharmaceutical applications: A systematic review. J Basic Microbiol 2021; 62:1044-1063. [PMID: 34766645 DOI: 10.1002/jobm.202100458] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 10/18/2021] [Accepted: 10/31/2021] [Indexed: 12/11/2022]
Abstract
Microalgae are regarded as a rich trove of diverse secondary metabolites that exert remarkable biological activities. In particular, microalgae-derived bioactive phenolic compounds (MBPCs) are a boon to biopharmaceutical and nutraceutical industries due to their diverse bioactivities, including antimicrobial, anticancer, antiviral, and immunomodulatory activities. The state-of-the-art green technologies for extraction and purification of MBPCs, along with the modern progress in the identification and characterization of MBPCs, have accelerated the discovery of novel active pharmaceutical compounds. However, several factors regulate the production of these bioactive phenolic compounds in microalgae. Furthermore, some microalgae species produce toxic phenolic compounds that negatively impact the aquatic ecosystem, animal, and human life. Therefore, the focus of this review paper is to bring into light the current innovations in bioprospection, extraction, purification, and characterization of MBPCs. This review is also aimed at a better understanding of the physicochemical factors regulating the production of MBPCs at an industrial scale. Finally, the present review covers the recent advances in toxicological evaluation, diverse applications, and future prospects of MBPCs in biopharmaceutical industries.
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Affiliation(s)
- Sahil Kapoor
- Department of Botany, MS University of Baroda, Vadodara, Gujarat, India.,Department of Botany, Goswami Ganesh Dutta S.D. College, Chandigarh, India
| | - Meenakshi Singh
- Department of Botany, MS University of Baroda, Vadodara, Gujarat, India.,Department of Ecology & Biodiversity, Terracon Ecotech Pvt. Ltd., Mumbai, Maharashtra, India
| | - Atul Srivastava
- Department of Botany, MS University of Baroda, Vadodara, Gujarat, India
| | - Murthy Chavali
- Office of the Dean (Research) & Department of Chemistry, Faculty of Science & Technology, Alliance University (Central Campus), Bengaluru, Karnataka, India.,NTRC-MCETRC and Aarshanano Composite Technologies Pvt. Ltd., Guntur, Andhra Pradesh, India
| | - K Chandrasekhar
- School of Civil and Environmental Engineering, Yonsei University, Seoul, Republic of Korea
| | - Pradeep Verma
- Bioprocess and Bioenergy Laboratory, Department of Microbiology, Central University of Rajasthan, Ajmer, Rajasthan, India
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15
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Oliver MJ, Farrant JM, Hilhorst HWM, Mundree S, Williams B, Bewley JD. Desiccation Tolerance: Avoiding Cellular Damage During Drying and Rehydration. ANNUAL REVIEW OF PLANT BIOLOGY 2020; 71:435-460. [PMID: 32040342 DOI: 10.1146/annurev-arplant-071219-105542] [Citation(s) in RCA: 112] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Desiccation of plants is often lethal but is tolerated by the majority of seeds and by vegetative tissues of only a small number of land plants. Desiccation tolerance is an ancient trait, lost from vegetative tissues following the appearance of tracheids but reappearing in several lineages when selection pressures favored its evolution. Cells of all desiccation-tolerant plants and seeds must possess a core set of mechanisms to protect them from desiccation- and rehydration-induced damage. This review explores how desiccation generates cell damage and how tolerant cells assuage the complex array of mechanical, structural, metabolic, and chemical stresses and survive.Likewise, the stress of rehydration requires appropriate mitigating cellular responses. We also explore what comparative genomics, both structural and responsive, have added to our understanding of cellular protection mechanisms induced by desiccation, and how vegetative desiccation tolerance circumvents destructive, stress-induced cell senescence.
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Affiliation(s)
- Melvin J Oliver
- Plant Genetics Research Unit, US Department of Agriculture, Agricultural Research Service, Columbia, Missouri 65211, USA
- Current affiliation: Division of Plant Sciences, Interdisciplinary Plant Group, University of Missouri, Columbia, Missouri 65211, USA;
| | - Jill M Farrant
- Department of Molecular and Cell Biology, University of Cape Town, Cape Town 7700, South Africa;
| | - Henk W M Hilhorst
- Laboratory of Plant Physiology, Wageningen University, 6706 PB Wageningen, The Netherlands;
| | - Sagadevan Mundree
- Centre for Tropical Crops and Biocommodities, Queensland University of Technology, Gardens Point Campus, Brisbane, 4001 Queensland, Australia; ,
| | - Brett Williams
- Centre for Tropical Crops and Biocommodities, Queensland University of Technology, Gardens Point Campus, Brisbane, 4001 Queensland, Australia; ,
| | - J Derek Bewley
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada;
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16
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Hartmann A, Glaser K, Holzinger A, Ganzera M, Karsten U. Klebsormidin A and B, Two New UV-Sunscreen Compounds in Green Microalgal Interfilum and Klebsormidium Species (Streptophyta) From Terrestrial Habitats. Front Microbiol 2020; 11:499. [PMID: 32292396 PMCID: PMC7118736 DOI: 10.3389/fmicb.2020.00499] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Accepted: 03/09/2020] [Indexed: 01/16/2023] Open
Abstract
The terrestrial green algal members of the genera Interfilum and Klebsormidium (Klebsormidiophyceae, Streptophyta) are found in biological soil crusts of extreme habitats around the world where they are regularly exposed, among other abiotic stress factors, to high levels of ultraviolet radiation (UVR). As a consequence those species synthesize and accumulate either one or two mycosporine-like amino acids (MAAs), but with a missing structural elucidation up to now. Therefore, in the present study both MAAs were chemically isolated and structurally elucidated. The two new compounds exhibit absorption maxima of 324 nm. MAA 1 has a molecular weight of 467 and MAA 2 of 305, and the latter (MAA 2) was identified as N-(4,5-dihydroxy-5-(hydroxymethyl)-2-methoxy-3-oxocyclohex-1-en-1-yl)-N-methylserine using one- and two-dimensional 1H and 13C-NMR spectroscopy. MAA 1 contains an additional sugar moiety. As trivial names for these two novel MAAs we suggest klebsormidin A and klebsormidin B. Different species from all previously described phylogenetic clades of Klebsormidiophyceae were chemically screened for their MAA composition in aqueous extracts using RP-HPLC and LC-MS. The novel klebsormidin A was present throughout all clades and hence could be suitable as a chemotaxonomic marker. Additionally, controlled UVR-exposure experiments with all investigated species showed that MAA biosynthesis and intracellular enrichment is strongly induced by short wavelengths, supporting the function of these compounds as natural UV-sunscreen as well as explaining the cosmopolitan distribution and ecological success of Interfilum and Klebsormidium in terrestrial habitats.
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Affiliation(s)
- Anja Hartmann
- Department of Pharmacognosy, Institute of Pharmacy, University of Innsbruck, Innsbruck, Austria
| | - Karin Glaser
- Institute of Biological Sciences, University of Rostock, Rostock, Germany
| | | | - Markus Ganzera
- Department of Pharmacognosy, Institute of Pharmacy, University of Innsbruck, Innsbruck, Austria
| | - Ulf Karsten
- Institute of Biological Sciences, University of Rostock, Rostock, Germany
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17
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Davies KM, Jibran R, Zhou Y, Albert NW, Brummell DA, Jordan BR, Bowman JL, Schwinn KE. The Evolution of Flavonoid Biosynthesis: A Bryophyte Perspective. FRONTIERS IN PLANT SCIENCE 2020; 11:7. [PMID: 32117358 PMCID: PMC7010833 DOI: 10.3389/fpls.2020.00007] [Citation(s) in RCA: 92] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Accepted: 01/07/2020] [Indexed: 05/04/2023]
Abstract
The flavonoid pathway is one of the best characterized specialized metabolite pathways of plants. In angiosperms, the flavonoids have varied roles in assisting with tolerance to abiotic stress and are also key for signaling to pollinators and seed dispersal agents. The pathway is thought to be specific to land plants and to have arisen during the period of land colonization around 550-470 million years ago. In this review we consider current knowledge of the flavonoid pathway in the bryophytes, consisting of the liverworts, hornworts, and mosses. The pathway is less characterized for bryophytes than angiosperms, and the first genetic and molecular studies on bryophytes are finding both commonalities and significant differences in flavonoid biosynthesis and pathway regulation between angiosperms and bryophytes. This includes biosynthetic pathway branches specific to each plant group and the apparent complete absence of flavonoids from the hornworts.
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Affiliation(s)
- Kevin M. Davies
- The New Zealand Institute for Plant and Food Research Limited, Palmerston North, New Zealand
| | - Rubina Jibran
- The New Zealand Institute for Plant and Food Research Limited, Palmerston North, New Zealand
| | - Yanfei Zhou
- The New Zealand Institute for Plant and Food Research Limited, Palmerston North, New Zealand
| | - Nick W. Albert
- The New Zealand Institute for Plant and Food Research Limited, Palmerston North, New Zealand
| | - David A. Brummell
- The New Zealand Institute for Plant and Food Research Limited, Palmerston North, New Zealand
| | - Brian R. Jordan
- Faculty of Agriculture and Life Sciences, Lincoln University, Christchurch, New Zealand
| | - John L. Bowman
- School of Biological Sciences, Monash University, Melbourne, VIC, Australia
| | - Kathy E. Schwinn
- The New Zealand Institute for Plant and Food Research Limited, Palmerston North, New Zealand
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18
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Cruces E, Rautenberger R, Cubillos VM, Ramírez-Kushel E, Rojas-Lillo Y, Lara C, Montory JA, Gómez I. Interaction of Photoprotective and Acclimation Mechanisms in Ulva rigida (Chlorophyta) in Response to Diurnal Changes in Solar Radiation in Southern Chile. JOURNAL OF PHYCOLOGY 2019; 55:1011-1027. [PMID: 31222742 DOI: 10.1111/jpy.12894] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Accepted: 05/24/2019] [Indexed: 06/09/2023]
Abstract
Species of the genus Ulva (Chlorophyta) are regarded as opportunistic organisms, which efficiently adjust their metabolism to the prevailing environmental conditions. In this study, changes in chlorophyll-a fluorescence-based photoinhibition of photosynthesis, electron transport rates, photosynthetic pigments, lipid peroxidation, total phenolic compounds, and antioxidant metabolism were investigated during a diurnal cycle of natural solar radiation in summer (for 12 h) under two treatments: photosynthetically active radiation (PAR: 400-700 nm) and PAR+ ultraviolet (UV) radiation (280-700 nm). In the presence of PAR alone, Ulva rigida showed dynamic photoinhibition, and photosynthetic parameters and pigment concentrations decreased with the intensification of the radiation. On the other hand, under PAR+UV conditions a substantial decline up to 43% was detected and an incomplete fluorescence recovery, also, P-I curve values remained low in relation to the initial condition. The phenolic compounds increased their concentration only in UV radiation treatments without showing a correlation with the antioxidant activity. The enzimatic activity of superoxide dismutase (SOD) and ascorbate peroxidase (APX) increased over 2-fold respect at initial values during the onset of light intensity. In contrast, catalase (CAT) increased its activity rapidly in response to the radiation stress to reach maxima at 10 a.m. and decreasing during solar. The present study suggests that U. rigida is capable of acclimating to natural radiation stress relies on a concerted action of various physiological mechanisms that act at different times of the day and under different levels of environmental stress.
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Affiliation(s)
- Edgardo Cruces
- Centro Integrativo de Biología y Química Aplicada (CIBQA), Universidad Bernardo O'Higgins, General Gana 1780, Santiago, 8370854, Chile
- Centro de Investigaciones Costeras-Universidad de Atacama (CIC-UDA), Universidad de Atacama, Avenida Copayapu 485, Copiapó, Atacama, Chile
| | - Ralf Rautenberger
- Division of Biotechnology and Plant Health, Department of Algae Production, Norwegian Institute for Bioeconomy Research (NIBIO), Kudalsveien 6, 8027, Bodø, Norway
| | - Víctor Mauricio Cubillos
- Instituto de Ciencias Marinas y Limnológicas, Universidad Austral de Chile, Valdivia, Chile
- Laboratorio Costero de Recursos Acuáticos de Calfuco, Universidad Austral de Chile, Valdivia, Chile
| | - Eduardo Ramírez-Kushel
- Instituto de Ciencias Marinas y Limnológicas, Universidad Austral de Chile, Valdivia, Chile
| | - Yesenia Rojas-Lillo
- Centro Integrativo de Biología y Química Aplicada (CIBQA), Universidad Bernardo O'Higgins, General Gana 1780, Santiago, 8370854, Chile
| | - Carlos Lara
- Centro de Investigación en Recursos Naturales y Sustentabilidad (CIRENYS), Universidad Bernardo O'Higgins, Santiago, 8370993, Chile
| | | | - Iván Gómez
- Instituto de Ciencias Marinas y Limnológicas, Universidad Austral de Chile, Valdivia, Chile
- Research Center FONDAP Dynamic of High Latitude Marine Ecosystems de (IDEAL), Valdivia, Chile
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19
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Brunetti C, Sebastiani F, Tattini M. Review: ABA, flavonols, and the evolvability of land plants. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2019; 280:448-454. [PMID: 30824025 DOI: 10.1016/j.plantsci.2018.12.010] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 11/26/2018] [Accepted: 12/12/2018] [Indexed: 05/03/2023]
Abstract
There is evidence that the ABA signaling pathway has greatly contributed to increase the complexity of land plants, thereby sustaining their ability to adapt in an ever-changing environment. The regulatory functions of the ABA signaling pathway go well beyond the movements of stomata and the dormancy of seeds. For instance, the ABA signaling regulates the flavonoid biosynthesis, consistent with the high integration of ABA and light signaling pathways, which occurs at the level of key signaling components, such as the bZIP transcription factors HY5 and ABI5. Here we focus on the regulation of 'colorless' (UV-absorbing) flavonol biosynthesis by the ABA signaling and, about how flavonols may regulate, in turn, the ABA signaling network. We discuss very recent findings that quercetin regulates the ABA signaling pathway, and hypothesize this might occur at the level of second messenger and perhaps of primary signaling components as well. We critically review old and recent suggestions of the primary roles played by flavonols, the ancient class of flavonoids already present in bryophytes, in the evolution of terrestrial plants. Our reasoning strongly supports the view that the ABA-flavonol relationship may represent a robust trait of land plants, and might have contributed to their adaptation on land.
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Affiliation(s)
- Cecilia Brunetti
- National Research Council of Italy, Trees and Timber Institute, Via Madonna del Piano 10, Sesto Fiorentino, I-50019, Florence, Italy; Department of Agri-Food Production and Environmental Sciences, University of Florence, Viale delle Idee 30, Sesto Fiorentino, I-50019, Florence, Italy
| | - Federico Sebastiani
- National Research Council of Italy, Institute for Sustainable Plant Protection, Via Madonna del Piano 10, Sesto Fiorentino, I-50019, Florence, Italy
| | - Massimiliano Tattini
- National Research Council of Italy, Institute for Sustainable Plant Protection, Via Madonna del Piano 10, Sesto Fiorentino, I-50019, Florence, Italy.
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20
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O'Neal SW, Hoover AM. Comparison of UVB effects on growth and induction of UVB screening compounds in isolates of metaphytic algae from temperate zone streams and ponds. JOURNAL OF PHYCOLOGY 2018; 54:818-828. [PMID: 30229900 DOI: 10.1111/jpy.12786] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Accepted: 07/18/2018] [Indexed: 06/08/2023]
Abstract
Filaments in the surface layers of metaphytic mats are exposed to high photon flux densities of PAR and UVBR. We investigated the effect of UVBR exposure on growth of eight isolates of common metaphytic algae (Cladophora, Mougeotia, Oedogonium, Pithophora, Spirogyra, and Zygnema) acclimated to either high or low PAR levels prior to UVBR exposure. All isolates acclimated to low PAR exhibited significant reductions in growth rate caused by the UVBR exposure (P < 0.05). Acclimation to high PAR resulted in seven of the isolates being more tolerant of the UVB exposure. The two Zygnema isolates exhibited the most pronounced effect of high PAR acclimation with growth rates of UVB exposed treatments being equal to that of controls (P > 0.05). High PAR acclimation also protected chlorophyll a levels in the Zygnema isolates. Absorption of UVB by methanol extracts increased 322%-381% for the two Zygnema isolates when high PAR acclimated. The broad absorption peak at 270 nm suggests that phenolic compounds were responsible. Previous studies have shown that Zygnema isolates from extreme environments tolerate UVBR and contain UVB screening compounds, but our results extend these adaptions to Zygnema from typical temperate zone habitats. Although none of the other metaphytic algae produced UVB absorbing compounds, they all exhibited higher growth rates under UVBR exposure following high PAR acclimation. This suggests that the algae evaluated have inducible defenses against UVBR exposure that coupled with their mat structure would provide an adaption to the challenging light environment in shallow-water habitats.
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Affiliation(s)
- Steven W O'Neal
- Department of Biological Sciences, Southwestern Oklahoma State University, 100 Campus Drive, Weatherford, Oklahoma, 73096, USA
| | - Angie M Hoover
- Division of Coastal Sciences Study, Gulf Coast Research Laboratory, 703 East Beach Drive, Ocean Springs, Mississippi, 39564, USA
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21
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Clayton WA, Albert NW, Thrimawithana AH, McGhie TK, Deroles SC, Schwinn KE, Warren BA, McLachlan ARG, Bowman JL, Jordan BR, Davies KM. UVR8-mediated induction of flavonoid biosynthesis for UVB tolerance is conserved between the liverwort Marchantia polymorpha and flowering plants. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2018; 96:503-517. [PMID: 30044520 DOI: 10.1111/tpj.14044] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Revised: 07/04/2018] [Accepted: 07/06/2018] [Indexed: 05/21/2023]
Abstract
Damaging UVB radiation is a major abiotic stress facing land plants. In angiosperms the UV RESISTANCE LOCUS8 (UVR8) photoreceptor coordinates UVB responses, including inducing biosynthesis of protective flavonoids. We characterised the UVB responses of Marchantia polymorpha (marchantia), the model species for the liverwort group of basal plants. Physiological, chemical and transcriptomic analyses were conducted on wild-type marchantia exposed to three different UVB regimes. CRISPR/Cas9 was used to obtain plant lines with mutations for components of the UVB signal pathway or the flavonoid biosynthetic pathway, and transgenics overexpressing the marchantia UVR8 sequence were generated. The mutant and transgenic lines were analysed for changes in flavonoid content, their response to UVB exposure, and transcript abundance of a set of 48 genes that included components of the UVB response pathway characterised for angiosperms. The marchantia UVB response included many components in common with Arabidopsis, including production of UVB-absorbing flavonoids, the central activator role of ELONGATED HYPOCOTYL5 (HY5), and negative feedback regulation by REPRESSOR OF UV-B PHOTOMORPHOGENESIS1 (RUP1). Notable differences included the greater importance of CHALCONE ISOMERASE-LIKE (CHIL). Mutants disrupted in the response pathway (hy5) or flavonoid production (chalcone isomerase, chil) were more easily damaged by UVB. Mutants (rup1) or transgenics (35S:MpMYB14) with increased flavonoid content had increased UVB tolerance. The results suggest that UVR8-mediated flavonoid induction is a UVB tolerance character conserved across land plants and may have been an early adaptation to life on land.
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Affiliation(s)
- William A Clayton
- The New Zealand Institute for Plant & Food Research Limited, Private Bag 11600, Palmerston North, 4442, New Zealand
- Faculty of Agriculture and Life Sciences, Lincoln University, Christchurch, 7647, New Zealand
| | - Nick W Albert
- The New Zealand Institute for Plant & Food Research Limited, Private Bag 11600, Palmerston North, 4442, New Zealand
| | - Amali H Thrimawithana
- The New Zealand Institute for Plant & Food Research Limited, Private Bag 92169, Auckland Mail Centre, Auckland, 1142, New Zealand
| | - Tony K McGhie
- The New Zealand Institute for Plant & Food Research Limited, Private Bag 11600, Palmerston North, 4442, New Zealand
| | - Simon C Deroles
- The New Zealand Institute for Plant & Food Research Limited, Private Bag 11600, Palmerston North, 4442, New Zealand
| | - Kathy E Schwinn
- The New Zealand Institute for Plant & Food Research Limited, Private Bag 11600, Palmerston North, 4442, New Zealand
| | - Ben A Warren
- The New Zealand Institute for Plant & Food Research Limited, Private Bag 92169, Auckland Mail Centre, Auckland, 1142, New Zealand
| | - Andrew R G McLachlan
- The New Zealand Institute for Plant & Food Research Limited, Private Bag 11600, Palmerston North, 4442, New Zealand
| | - John L Bowman
- School of Biological Sciences, Monash University, Melbourne, Victoria, 3800, Australia
| | - Brian R Jordan
- Faculty of Agriculture and Life Sciences, Lincoln University, Christchurch, 7647, New Zealand
| | - Kevin M Davies
- The New Zealand Institute for Plant & Food Research Limited, Private Bag 11600, Palmerston North, 4442, New Zealand
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Holzinger A, Albert A, Aigner S, Uhl J, Schmitt-Kopplin P, Trumhová K, Pichrtová M. Arctic, Antarctic, and temperate green algae Zygnema spp. under UV-B stress: vegetative cells perform better than pre-akinetes. PROTOPLASMA 2018; 255:1239-1252. [PMID: 29470709 PMCID: PMC5994220 DOI: 10.1007/s00709-018-1225-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Accepted: 02/08/2018] [Indexed: 05/13/2023]
Abstract
Species of Zygnema form macroscopically visible mats in polar and temperate terrestrial habitats, where they are exposed to environmental stresses. Three previously characterized isolates (Arctic Zygnema sp. B, Antarctic Zygnema sp. C, and temperate Zygnema sp. S) were tested for their tolerance to experimental UV radiation. Samples of young vegetative cells (1 month old) and pre-akinetes (6 months old) were exposed to photosynthetically active radiation (PAR, 400-700 nm, 400 μmol photons m-2 s-1) in combination with experimental UV-A (315-400 nm, 5.7 W m-2, no UV-B), designated as PA, or UV-A (10.1 W m-2) + UV-B (280-315 nm, 1.0 W m-2), designated as PAB. The experimental period lasted for 74 h; the radiation period was 16 h PAR/UV-A per day, or with additional UV-B for 14 h per day. The effective quantum yield, generally lower in pre-akinetes, was mostly reduced during the UV treatment, and recovery was significantly higher in young vegetative cells vs. pre-akinetes during the experiment. Analysis of the deepoxidation state of the xanthophyll-cycle pigments revealed a statistically significant (p < 0.05) increase in Zygnema spp. C and S. The content of UV-absorbing phenolic compounds was significantly higher (p < 0.05) in young vegetative cells compared to pre-akinetes. In young vegetative Zygnema sp. S, these phenolic compounds significantly increased (p < 0.05) upon PA and PAB. Transmission electron microscopy showed an intact ultrastructure with massive starch accumulations at the pyrenoids under PA and PAB. A possible increase in electron-dense bodies in PAB-treated cells and the occurrence of cubic membranes in the chloroplasts are likely protection strategies. Metabolite profiling by non-targeted RP-UHPLC-qToF-MS allowed a clear separation of the strains, but could not detect changes due to the PA and PAB treatments. Six hundred seventeen distinct molecular masses were detected, of which around 200 could be annotated from databases. These results indicate that young vegetative cells can adapt better to the experimental UV-B stress than pre-akinetes.
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Affiliation(s)
- Andreas Holzinger
- Department of Botany, Functional Plant Biology, University of Innsbruck, Sternwartestraße 15, 6020, Innsbruck, Austria.
| | - Andreas Albert
- Research Unit Environmental Simulation, Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt GmbH, Ingolstaedter Landstr. 1, 85764, Neuherberg, Germany
| | - Siegfried Aigner
- Department of Botany, Functional Plant Biology, University of Innsbruck, Sternwartestraße 15, 6020, Innsbruck, Austria
| | - Jenny Uhl
- Research Unit Analytical BioGeoChemistry, Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt GmbH, Ingolstaedter Landstr. 1, 85764, Neuherberg, Germany
| | - Philippe Schmitt-Kopplin
- Research Unit Analytical BioGeoChemistry, Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt GmbH, Ingolstaedter Landstr. 1, 85764, Neuherberg, Germany
| | - Kateřina Trumhová
- Faculty of Science, Department of Botany, Charles University, Benátská 2, 128 01, Prague, Czech Republic
| | - Martina Pichrtová
- Faculty of Science, Department of Botany, Charles University, Benátská 2, 128 01, Prague, Czech Republic
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Aigner S, Herburger K, Holzinger A, Karsten U. Epilithic Chamaesiphon (Synechococcales, Cyanobacteria) species in mountain streams of the Alps-interspecific differences in photo-physiological traits. JOURNAL OF APPLIED PHYCOLOGY 2017; 30:1125-1134. [PMID: 29755206 PMCID: PMC5928177 DOI: 10.1007/s10811-017-1328-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Revised: 10/19/2017] [Accepted: 10/19/2017] [Indexed: 06/08/2023]
Abstract
Many alpine streams inhabit conspicuous epilithic biofilms on pebbles and rocks that are formed by members of the cyanobacterial genus Chamaesiphon (Synechococcales). In the Austrian Alps, some Chamaesiphon species can even overgrow up to 70% of the surface of river rocks, and hence they must play an important but still unstudied ecological role in the organic matter flux. Since photo-biological traits have not been investigated so far, photosynthetic features, pigments, and UV-sunscreen compounds were studied in three Chamaesiphon morphospecies (C. geitleri, C. polonicus, C. starmachii). These species form conspicuously differently colored spots on cobbles and boulders in the alpine streams. While C. polonicus typically forms red crusts on flat pebble conglomerate, C. geitleri and C. starmachii are characterized by dark brown and black biofilms in the field, respectively. Photosynthesis-irradiance (PE) curves indicate that all three Chamaesiphon species have different light requirements for photosynthesis, with C. starmachii and C. polonicus preferring high and low photon fluence rates, respectively, while C. geitleri takes a position in between. This low-light requirement of C. polonicus is also reflected in ca. ten-times lower chlorophyll a, zeaxanthin, and ß-carotene concentrations, as well as in a lack of the UV-sunscreen scytonemin. All Chamaesiphon morphospecies exhibit the mycosporine-like amino acid porphyra-334. The physiological and biochemical data indicate strong intraspecific differences in photosynthetic activity and pigment patterns, which explain well the distinct preferences of the three studied Chamaesiphon morphospecies for sun-exposed or shaded habitats.
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Affiliation(s)
- Siegfried Aigner
- Institute of Botany, University of Innsbruck, Sternwarte Strasse 15, A-6020 Innsbruck, Austria
| | - Klaus Herburger
- Institute of Botany, University of Innsbruck, Sternwarte Strasse 15, A-6020 Innsbruck, Austria
| | - Andreas Holzinger
- Institute of Botany, University of Innsbruck, Sternwarte Strasse 15, A-6020 Innsbruck, Austria
| | - Ulf Karsten
- Institute of Biological Sciences, University of Rostock, Albert-Einstein-Strasse 3, D-18057 Rostock, Germany
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Donner A, Glaser K, Borchhardt N, Karsten U. Ecophysiological Response on Dehydration and Temperature in Terrestrial Klebsormidium (Streptophyta) Isolated from Biological Soil Crusts in Central European Grasslands and Forests. MICROBIAL ECOLOGY 2017; 73:850-864. [PMID: 28011994 DOI: 10.1007/s00248-016-0917-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Accepted: 12/09/2016] [Indexed: 05/22/2023]
Abstract
The green algal genus Klebsormidium (Klebsormidiophyceae, Streptophyta) is a typical member of biological soil crusts (BSCs) worldwide. Ecophysiological studies focused so far on individual strains and thus gave only limited insight on the plasticity of this genus. In the present study, 21 Klebsormidium strains (K. dissectum, K. flaccidum, K. nitens, K. subtile) from temperate BSCs in Central European grassland and forest sites were investigated. Photosynthetic performance under desiccation and temperature stress was measured under identical controlled conditions. Photosynthesis decreased during desiccation within 335-505 min. After controlled rehydration, most isolates recovered, but with large variances between single strains and species. However, all K. dissectum strains had high recovery rates (>69%). All 21 Klebsormidium isolates exhibited the capability to grow under a wide temperature range. Except one strain, all others grew at 8.5 °C and four strains were even able to grow at 6.2 °C. Twenty out of 21 Klebsormidium isolates revealed an optimum growth temperature >17 °C, indicating psychrotrophic features. Growth rates at optimal temperatures varied between strains from 0.26 to 0.77 μ day-1. Integrating phylogeny and ecophysiological traits, we found no phylogenetic signal in the traits investigated. However, multivariate statistical analysis indicated an influence of the recovery rate and growth rate. The results demonstrate a high infraspecific and interspecific physiological plasticity, and thus wide ecophysiological ability to cope with strong environmental gradients. This might be the reason why members of the genus Klebsormidium successfully colonize terrestrial habitats worldwide.
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Affiliation(s)
- Antje Donner
- Institute of Biological Sciences, Applied Ecology and Phycology, University of Rostock, Albert-Einstein-Strasse 3, 18059, Rostock, Germany.
| | - Karin Glaser
- Institute of Biological Sciences, Applied Ecology and Phycology, University of Rostock, Albert-Einstein-Strasse 3, 18059, Rostock, Germany
| | - Nadine Borchhardt
- Institute of Biological Sciences, Applied Ecology and Phycology, University of Rostock, Albert-Einstein-Strasse 3, 18059, Rostock, Germany
| | - Ulf Karsten
- Institute of Biological Sciences, Applied Ecology and Phycology, University of Rostock, Albert-Einstein-Strasse 3, 18059, Rostock, Germany
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25
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Terrestrial Microalgae: Novel Concepts for Biotechnology and Applications. PROGRESS IN BOTANY VOL. 79 2017. [DOI: 10.1007/124_2017_10] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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26
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Aigner S, Holzinger A, Karsten U, Kranner I. The freshwater red alga Batrachospermum turfosum (Florideophyceae) can acclimate to a wide range of light and temperature conditions. PHYCOLOGIA 2017; 52:238-249. [PMID: 28413232 PMCID: PMC5390863 DOI: 10.1080/09670262.2016.1274430] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Revised: 11/11/2016] [Accepted: 12/03/2016] [Indexed: 05/22/2023]
Abstract
Batrachospermum turfosum Bory is one of the generalists among the few red algae that have adapted to freshwater habitats, occurring in a variety of primarily shaded, nutrient-poor micro-habitats with lotic (running) or lentic (standing) waters. Seasonal variations in water level and canopy cover can expose this sessile alga to widely fluctuating temperatures, solar irradiation and nutrient availability. Here we report on the ecophysiology of B. turfosum collected from an ultra-oligotrophic bog pool in the Austrian Alps. Photosynthesis as a function of photon fluence density (PFD) and temperature was studied by measuring oxygen evolution in combination with chlorophyll fluorescence. In addition, the effects of ultraviolet radiation (UVR) on photosynthetic pigments were analysed using HPLC and spectrophotometric methods, and cellular ultrastructure was studied using transmission electron microscopy. We found that B. turfosum is adapted to low light, with a light compensation point (Ic) and a light saturation point (Ik) of 8.4 and 29.7 μmol photons m- 2 s-1, respectively, but also tolerates higher PFDs of ~1000 μmol photons m-2 s-1, and is capable of net photosynthesis at temperatures between 5°C and 35°C. Exposure to either UV-A or UV-AB for 102 h led to a strong transient drop in effective quantum yield (ΔF/FM'), followed by an acclimation to about 70% of initial ΔF/FM' values. Ultrastructural changes included the accumulation of plastoglobules and dilated membranes after UVR treatment. Although all photosynthetic pigments strongly decreased upon UVR exposure and no UV-photoprotectants (e.g. mycosporine-like amino acids) could be detected, the alga was capable of recovering ΔF/FM' and phycobiliproteins after UVR treatment. In summary, B. turfosum tolerates a wide range of irradiation and temperature regimes, and these traits may be the basis for its successful adaptation to challenging environments.
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Affiliation(s)
- Siegfried Aigner
- University of Innsbruck, Institute of Botany, Functional Plant Biology, Sternwartestraße 15, 6020 Innsbruck, Austria
| | - Andreas Holzinger
- University of Innsbruck, Institute of Botany, Functional Plant Biology, Sternwartestraße 15, 6020 Innsbruck, Austria
| | - Ulf Karsten
- University of Rostock, Institute of Biological Sciences, Applied Ecology, Albert-Einstein-Straße 3, D-18057 Rostock, Germany
| | - Ilse Kranner
- University of Innsbruck, Institute of Botany, Functional Plant Biology, Sternwartestraße 15, 6020 Innsbruck, Austria
- Corresponding author: Ilse Kranner, Fax: +43-0512-507-2715,
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Herburger K, Karsten U, Holzinger A. Entransia and Hormidiella, sister lineages of Klebsormidium (Streptophyta), respond differently to light, temperature, and desiccation stress. PROTOPLASMA 2016; 253:1309-23. [PMID: 26439247 PMCID: PMC4710678 DOI: 10.1007/s00709-015-0889-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Accepted: 09/21/2015] [Indexed: 05/22/2023]
Abstract
The green-algal class Klebsormidiophyceae (Streptophyta), which occurs worldwide, comprises the genera Klebsormidium, Interfilum, Entransia, and Hormidiella. Ecophysiological research has so far focused on the first two genera because they are abundant in biological soil crust communities. The present study investigated the photosynthetic performances of Hormidiella attenuata and two strains of Entransia fimbriata under light, temperature, and desiccation stress. Their ultrastructure was compared using transmission electron microscopy. The two Entransia strains showed similar physiological responses. They used light more efficiently than Hormidiella, as indicated by higher oxygen production and relative electron transport rate under low light conditions, lower light saturation and compensation points, and higher maximum oxygen production during light saturation. Their requirement for low light levels explains the restriction of Entransia to dim limnetic habitats. In contrast, Hormidiella, which prefers drier soil habitats, responded to light gradients similarly to other aero-terrestrial green algae. Compared to Entransia, Hormidiella was less affected by short-term desiccation, and rehydration allowed full recovery of the photosynthetic performance. Nevertheless, both strains of Entransia coped with low water availability better than other freshwater algae. Photosynthetic oxygen production in relation to respiratory consumption was higher in low temperatures (Entransia: 5 °C, Hormidiella: 10 °C) and the ratio decreased with increasing temperatures. Hormidiella exhibited conspicuous triangular spaces in the cell wall corners, which were filled either with undulating cell wall material or with various inclusions. These structures are commonly seen in various members of Klebsormidiophyceae. The data revealed significant differences between Hormidiella and Entransia, but appropriate adaptations to their respective habitats.
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Affiliation(s)
- Klaus Herburger
- Institute of Botany, Functional Plant Biology, University of Innsbruck, Sternwartestraße 15, A-6020, Innsbruck, Austria
| | - Ulf Karsten
- Institute of Biological Sciences, Applied Ecology and Phycology, University of Rostock, Albert-Einstein-Straße 3, D-18059, Rostock, Germany
| | - Andreas Holzinger
- Institute of Botany, Functional Plant Biology, University of Innsbruck, Sternwartestraße 15, A-6020, Innsbruck, Austria.
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Herburger K, Remias D, Holzinger A. The green alga Zygogonium ericetorum (Zygnematophyceae, Charophyta) shows high iron and aluminium tolerance: protection mechanisms and photosynthetic performance. FEMS Microbiol Ecol 2016; 92:fiw103. [PMID: 27178434 PMCID: PMC4909054 DOI: 10.1093/femsec/fiw103] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Revised: 01/21/2016] [Accepted: 04/27/2016] [Indexed: 12/27/2022] Open
Abstract
Streptophyte green algae, ancestors of Embryophytes, occur frequently in terrestrial habitats being exposed to high light intensities, water scarcity and potentially toxic metal cations under acidic conditions. The filamentous Zygogonium ericetorum synthesizes a purple vacuolar ferrous pigment, which is lost after aplanospore formation. However, it is unknown whether this cellular reorganization also removes excessive iron from the protoplast and how Z. ericetorum copes with high concentrations of aluminium. Here we show that aplanospore formation shifts iron into the extracellular space of the algal filament. Upon germination of aplanospores, aluminium is bound in the parental cell wall. Both processes reduce iron and aluminium in unpigmented filaments. Comparison of the photosynthetic oxygen production in response to light and temperature gradients in two different Z. ericetorum strains from an Austrian alpine and a Scottish highland habitat revealed lower values in the latter strain. In contrast, the Scottish strain showed a higher optimum quantum yield of PSII during desiccation stress followed by rehydration. Furthermore, pigmented filaments of both strains exhibited a higher light and temperature dependent oxygen production when compared to the unpigmented phenotype. Our results demonstrate a high metal tolerance of Z. ericetorum, which is crucial for surviving in acidic terrestrial habitats.
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Affiliation(s)
- Klaus Herburger
- Institute of Botany, Functional Plant Biology, University of Innsbruck, Sternwartestraße 15, A-6020 Innsbruck, Austria
| | - Daniel Remias
- University of Applied Sciences Upper Austria, School of Engineering, Stelzhamerstraße 23, A-4600 Wels, Austria
| | - Andreas Holzinger
- Institute of Botany, Functional Plant Biology, University of Innsbruck, Sternwartestraße 15, A-6020 Innsbruck, Austria
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Holzinger A, Allen MC, Deheyn DD. Hyperspectral imaging of snow algae and green algae from aeroterrestrial habitats. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2016; 162:412-420. [PMID: 27442511 DOI: 10.1016/j.jphotobiol.2016.07.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Revised: 07/01/2016] [Accepted: 07/03/2016] [Indexed: 10/21/2022]
Abstract
Snow algae and green algae living in aeroterrestrial habitats are ideal objects to study adaptation to high light irradiation. Here, we used a detailed description of the spectral properties as a proxy for photo-acclimation/protection in snow algae (Chlamydomonas nivalis, Chlainomonas sp. and Chloromonas sp.) and charophyte green algae (Zygnema sp., Zygogonium ericetorum and Klebsormidium crenulatum). The hyperspectral microscopic mapping and imaging technique allowed us to acquire total absorption spectra of these microalgae in the waveband of 400-900nm. Particularly in Chlamydomonas nivalis and Chlainomonas sp., a high absorbance between 400-550nm was observed, due to naturally occurring secondary carotenoids; in Chloromonas sp. and in the charopyhte algae this high absorbance was missing, the latter being close relatives to land plants. To investigate if cellular water loss has an influence on the spectral properties, the cells were plasmolysed in sorbitol or desiccated at ambient air. While in snow algae, these treatments did hardly change the spectral properties, in the charopyhte algae the condensation of the cytoplasm and plastids increased the absorbance in the lower waveband of 400-500nm. These changes might be ecologically relevant and photoprotective, as aeroterrestrial algae are naturally exposed to occasional water limitation, leading to desiccation, which are conditions usually occurring together with higher irradiation.
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Affiliation(s)
- Andreas Holzinger
- Institute of Botany, Functional Plant Biology, University of Innsbruck, Sternwartestrasse 15, 6020 Innsbruck, Austria.
| | - Michael C Allen
- Marine Biology Research Division, Scripps Institution of Oceanography, University of California San Diego, 9500 Gilman Dr., La Jolla, CA 92093-0202, USA
| | - Dimitri D Deheyn
- Marine Biology Research Division, Scripps Institution of Oceanography, University of California San Diego, 9500 Gilman Dr., La Jolla, CA 92093-0202, USA.
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Stancheva R, Herburger K, Sheath RG, Holzinger A. Conjugation morphology of Zygogonium ericetorum (Zygnematophyceae, Charophyta) from a high alpine habitat. JOURNAL OF PHYCOLOGY 2016; 52:131-134. [PMID: 26869733 PMCID: PMC4747114 DOI: 10.1111/jpy.12363] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 10/13/2015] [Indexed: 05/29/2023]
Abstract
Reproductive characteristics are important for defining taxonomic groups of filamentous Zygnematophyceae, but they have not been fully observed in the genus Zygogonium. Specimens of Z. ericetorum previously studied and used to clarify the generic concept lacked fertile material, which was obtained recently. This study illustrates for the first time, using color light microscopic and fluorescence images, a consequent conjugation stage in Z. ericetorum, including completely developed zygospores and purple cytoplasmic residue content left outside the zygospores, similar to aplanospore formation. Structures confirmed earlier reports and provided new observation informative regarding phylogenetically relevant reproductive characters of Z. ericetorum.
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Holzinger A, Pichrtová M. Abiotic Stress Tolerance of Charophyte Green Algae: New Challenges for Omics Techniques. FRONTIERS IN PLANT SCIENCE 2016; 7:678. [PMID: 27242877 PMCID: PMC4873514 DOI: 10.3389/fpls.2016.00678] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Accepted: 05/02/2016] [Indexed: 05/20/2023]
Abstract
Charophyte green algae are a paraphyletic group of freshwater and terrestrial green algae, comprising the classes of Chlorokybophyceae, Coleochaetophyceae, Klebsormidiophyceae, Zygnematophyceae, Mesostigmatophyceae, and Charo- phyceae. Zygnematophyceae (Conjugating green algae) are considered to be closest algal relatives to land plants (Embryophyta). Therefore, they are ideal model organisms for studying stress tolerance mechanisms connected with transition to land, one of the most important events in plant evolution and the Earth's history. In Zygnematophyceae, but also in Coleochaetophyceae, Chlorokybophyceae, and Klebsormidiophyceae terrestrial members are found which are frequently exposed to naturally occurring abiotic stress scenarios like desiccation, freezing and high photosynthetic active (PAR) as well as ultraviolet (UV) irradiation. Here, we summarize current knowledge about various stress tolerance mechanisms including insight provided by pioneer transcriptomic and proteomic studies. While formation of dormant spores is a typical strategy of freshwater classes, true terrestrial groups are stress tolerant in vegetative state. Aggregation of cells, flexible cell walls, mucilage production and accumulation of osmotically active compounds are the most common desiccation tolerance strategies. In addition, high photophysiological plasticity and accumulation of UV-screening compounds are important protective mechanisms in conditions with high irradiation. Now a shift from classical chemical analysis to next-generation genome sequencing, gene reconstruction and annotation, genome-scale molecular analysis using omics technologies followed by computer-assisted analysis will give new insights in a systems biology approach. For example, changes in transcriptome and role of phytohormone signaling in Klebsormidium during desiccation were recently described. Application of these modern approaches will deeply enhance our understanding of stress reactions in an unbiased non-targeted view in an evolutionary context.
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Affiliation(s)
- Andreas Holzinger
- Unit of Functional Plant Biology, Institute of Botany, University of Innsbruck, InnsbruckAustria
- *Correspondence: Andreas Holzinger,
| | - Martina Pichrtová
- Unit of Functional Plant Biology, Institute of Botany, University of Innsbruck, InnsbruckAustria
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Herburger K, Holzinger A. Localization and Quantification of Callose in the Streptophyte Green Algae Zygnema and Klebsormidium: Correlation with Desiccation Tolerance. PLANT & CELL PHYSIOLOGY 2015; 56:2259-70. [PMID: 26412780 PMCID: PMC4650865 DOI: 10.1093/pcp/pcv139] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Accepted: 09/18/2015] [Indexed: 05/20/2023]
Abstract
Freshwater green algae started to colonize terrestrial habitats about 460 million years ago, giving rise to the evolution of land plants. Today, several streptophyte green algae occur in aero-terrestrial habitats with unpredictable fluctuations in water availability, serving as ideal models for investigating desiccation tolerance. We tested the hypothesis that callose, a β-d-1,3-glucan, is incorporated specifically in strained areas of the cell wall due to cellular water loss, implicating a contribution to desiccation tolerance. In the early diverging genus Klebsormidium, callose was drastically increased already after 30 min of desiccation stress. Localization studies demonstrated an increase in callose in the undulating cross cell walls during cellular water loss, allowing a regulated shrinkage and expansion after rehydration. This correlates with a high desiccation tolerance demonstrated by a full recovery of the photosynthetic yield visualized at the subcellular level by Imaging-PAM. Furthermore, abundant callose in terminal cell walls might facilitate cell detachment to release dispersal units. In contrast, in the late diverging Zygnema, the callose content did not change upon desiccation for up to 3.5 h and was primarily localized in the corners between individual cells and at terminal cells. While these callose deposits still imply reduction of mechanical damage, the photosynthetic yield did not recover fully in the investigated young cultures of Zygnema upon rehydration. The abundance and specific localization of callose correlates with the higher desiccation tolerance in Klebsormidium when compared with Zygnema.
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Affiliation(s)
- Klaus Herburger
- University of Innsbruck, Institute of Botany, Functional Plant Biology, Sternwartestrasse 15, 6020 Innsbruck, Austria
| | - Andreas Holzinger
- University of Innsbruck, Institute of Botany, Functional Plant Biology, Sternwartestrasse 15, 6020 Innsbruck, Austria
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Herburger K, Lewis LA, Holzinger A. Photosynthetic efficiency, desiccation tolerance and ultrastructure in two phylogenetically distinct strains of alpine Zygnema sp. (Zygnematophyceae, Streptophyta): role of pre-akinete formation. PROTOPLASMA 2015; 252:571-89. [PMID: 25269628 PMCID: PMC4335129 DOI: 10.1007/s00709-014-0703-3] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Accepted: 09/12/2014] [Indexed: 05/20/2023]
Abstract
Two newly isolated strains of green algae from alpine regions were compared physiologically at different culture ages (1, 6, 9 and 15 months). The strains of Zygnema sp. were from different altitudes ('Saalach' (S), 440 m above sea level (a.s.l.), SAG 2419 and 'Elmau-Alm' (E-A), 1,500 m a.s.l., SAG 2418). Phylogenetic analysis of rbcL sequences grouped the strains into different major subclades of the genus. The mean diameters of the cells were 23.2 μm (Zygnema S) and 18.7 μm (Zygnema E-A) but were reduced significantly with culture age. The photophysiological response between the strains differed significantly; Zygnema S had a maximal relative electron transport rate (rETR max) of 103.4 μmol electrons m(-2) s(-1), Zygnema E-A only 61.7 μmol electrons m(-2) s(-1), and decreased significantly with culture age. Both strains showed a low-light adaption and the absence of strong photoinhibition up to 2,000 μmol photons m(-2) s(-1). Photosynthetic oxygen production showed similar results (P max Zygnema S, 527.2 μmol O2 h(-1) mg(-1) chlorophyll (chl.) a, Zygnema E-A, 390.7 μmol O2 h(-1) mg(-1) chl. a); the temperature optimum was at 35 °C for Zygnema S and 30 °C for Zygnema E-A. Increasing culture age moreover leads to the formation of pre-akinetes, which accumulate storage products as revealed by light and transmission electron microscopy. Desiccation at 84 % relative air humidity (RH) lead to a reduction of the effective quantum yield of photosystem II (PSII) (ΔFv/Fm') to zero between 90 to 120 min (Zygnema S) and between 30 to 60 min (Zygnema E-A), depending on the culture age. A partial recovery of ΔFv/Fm' was only observed in older cultures. We conclude that pre-akinetes are crucial for the aeroterrestrial lifestyle of Zygnema.
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Affiliation(s)
- K. Herburger
- Institute of Botany, Functional Plant Biology, University of Innsbruck, Sternwartestrasse 15, 6020 Innsbruck, Austria
| | - L. A. Lewis
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT 06269-3043 USA
| | - A. Holzinger
- Institute of Botany, Functional Plant Biology, University of Innsbruck, Sternwartestrasse 15, 6020 Innsbruck, Austria
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Pichrtová M, Kulichová J, Holzinger A. Nitrogen limitation and slow drying induce desiccation tolerance in conjugating green algae (Zygnematophyceae, Streptophyta) from polar habitats. PLoS One 2014; 9:e113137. [PMID: 25398135 PMCID: PMC4232603 DOI: 10.1371/journal.pone.0113137] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Accepted: 10/21/2014] [Indexed: 01/14/2023] Open
Abstract
Background Filamentous Zygnematophyceae are typical components of algal mats in the polar hydro-terrestrial environment. Under field conditions, they form senescent vegetative cells, designated as pre-akinetes, which are tolerant to desiccation and osmotic stress. Key Findings Pre-akinete formation and desiccation tolerance was investigated experimentally under monitored laboratory conditions in four strains of Arctic and Antarctic isolates with vegetative Zygnema sp. morphology. Phylogenetic analyses of rbcL sequences revealed one Arctic strain as genus Zygnemopsis, phylogenetically distant from the closely related Zygnema strains. Algae were cultivated in liquid or on solidified medium (9 weeks), supplemented with or lacking nitrogen. Nitrogen-free cultures (liquid as well as solidified) consisted of well-developed pre-akinetes after this period. Desiccation experiments were performed at three different drying rates (rapid: 10% relative humidity, slow: 86% rh and very slow); viability, effective quantum yield of PS II, visual and ultrastructural changes were monitored. Recovery and viability of pre-akinetes were clearly dependent on the drying rate: slower desiccation led to higher levels of survival. Pre-akinetes survived rapid drying after acclimation by very slow desiccation. Conclusions The formation of pre-akinetes in polar Zygnema spp. and Zygnemopsis sp. is induced by nitrogen limitation. Pre-akinetes, modified vegetative cells, rather than specialized stages of the life cycle, can be hardened by mild desiccation stress to survive rapid drying. Naturally hardened pre-akinetes play a key role in stress tolerance and dispersal under the extreme conditions of polar regions, where sexual reproduction and production of dormant stages is largely suppressed.
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Affiliation(s)
- Martina Pichrtová
- Charles University in Prague, Faculty of Science, Department of Botany, Prague, Czech Republic
- Academy of Sciences of the Czech Republic, Institute of Botany, Třeboň, Czech Republic
| | - Jana Kulichová
- Charles University in Prague, Faculty of Science, Department of Botany, Prague, Czech Republic
| | - Andreas Holzinger
- University of Innsbruck, Institute of Botany, Functional Plant Biology, Innsbruck, Austria
- * E-mail:
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Stancheva R, Hall JD, Herburger K, Lewis LA, McCourt RM, Sheath RG, Holzinger A. Phylogenetic position of Zygogonium ericetorum (zygnematophyceae, charophyta) from a high alpine habitat and ultrastructural characterization of unusual aplanospores. JOURNAL OF PHYCOLOGY 2014; 50:790-803. [PMID: 25810560 PMCID: PMC4370237 DOI: 10.1111/jpy.12229] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Characeae (Charophyceae, Charophyta) contains two tribes with six genera: tribe Chareae with four genera and tribe Nitelleae, which includes Tolypella and Nitella. This paper uses molecular and morphological data to elucidate the phylogeny of Tolypella species in North America. In the most comprehensive taxonomic treatment of Characeae, 16 Tolypella species worldwide were subsumed into two species, T. intricata and T. nidifica, in two sections, Rothia and Tolypella respectively. It was further suggested that Tolypella might be a derived group within Nitella. In this investigation into species diversity and relationships in North American Tolypella, sequence data from the plastid genes atpB, psbC, and rbcL were assembled for a broad range of charophycean and land plant taxa. Molecular data were used in conjunction with morphology to test monophyly of the genus and species within it. Phylogenetic analyses of the sequence data showed that Characeae is monophyletic but that Nitelleae is paraphyletic with Tolypella sister to a monophyletic Nitella + Chareae. The results also supported the monophyly of Tolypella and the sections Rothia and Tolypella. Morphologically defined species were supported as clades with little or no DNA sequence differences. In addition, molecular data revealed several lineages and a new species (T. ramosissima sp. nov.), which suggests greater species diversity in Tolypella than previously recognized.
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Affiliation(s)
- Rosalina Stancheva
- Department of Biological Sciences, California State University San Marcos, San Marcos, California 92096, USA
| | - John D. Hall
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park, Maryland 20742, USA, Department of Botany, Academy of Natural Sciences, Philadelphia, Pennsylvania 19103, USA
| | - Klaus Herburger
- Institute of Botany, University of Innsbruck, Sternwartestraße 15, Innsbruck A-6020, Austria
| | - Louise A. Lewis
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut 06269, USA
| | - Richard M. McCourt
- Department of Botany, Academy of Natural Sciences, Philadelphia, Pennsylvania 19103, USA, Department of Biodiversity, Earth, and Environmental Sciences, Drexel University, Philadelphia, Pennsylvania 19104, USA
| | - Robert G. Sheath
- Department of Biological Sciences, California State University San Marcos, San Marcos, California 92096, USA
| | - Andreas Holzinger
- Institute of Botany, University of Innsbruck, Sternwartestraße 15, Innsbruck A-6020, Austria
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Pichrtová M, Hájek T, Elster J. Osmotic stress and recovery in field populations of Zygnema sp. (Zygnematophyceae, Streptophyta) on Svalbard (High Arctic) subjected to natural desiccation. FEMS Microbiol Ecol 2014; 89:270-80. [PMID: 24476153 DOI: 10.1111/1574-6941.12288] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2013] [Revised: 01/06/2014] [Accepted: 01/16/2014] [Indexed: 12/01/2022] Open
Abstract
Zygnema is a genus of filamentous green algae belonging to the class of Zygnematophyceae (Streptophyta). In the Arctic, it typically forms extensive mats in habitats that regularly dry out during summer, and therefore, mechanisms of stress resistance are expected. We investigated its natural populations with respect to production of specialized desiccation-resistant cells and osmotic acclimation. Six populations in various stages of natural desiccation were selected, from wet biomass floating in water to dried paper-like crusts. After rewetting, plasmolysis and osmotic stress effects were studied using hypertonic sorbitol solutions, and the physiological state was estimated using chlorophyll a fluorescence parameters. All populations of Zygnema sp. formed stationary-phase cells filled with storage products. In green algal research, such cells are traditionally called akinetes. However, the populations differed in their reaction to osmotic stress. Whereas the wet-collected samples were strongly impaired, the osmotic stress resistance of the naturally dried samples was comparable to that of true aeroterrestrial algae. We showed that arctic populations of Zygnema acclimate well to natural desiccation via hardening that is mediated by slow desiccation. As no other types of specialized cells were observed, we assume that the naturally hardened akinetes also play a key role in winter survival.
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Affiliation(s)
- Martina Pichrtová
- Institute of Botany, Academy of Sciences of the Czech Republic, Třeboň, Czech Republic; Department of Botany, Faculty of Science, Charles University in Prague, Prague, Czech Republic
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Karsten U, Holzinger A. Green algae in alpine biological soil crust communities: acclimation strategies against ultraviolet radiation and dehydration. BIODIVERSITY AND CONSERVATION 2014; 23:1845-1858. [PMID: 24954980 PMCID: PMC4058318 DOI: 10.1007/s10531-014-0653-2] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Revised: 01/22/2014] [Accepted: 02/14/2014] [Indexed: 05/20/2023]
Abstract
Green algae are major components of biological soil crusts in alpine habitats. Together with cyanobacteria, fungi and lichens, green algae form a pioneer community important for the organisms that will succeed them. In their high altitudinal habitat these algae are exposed to harsh and strongly fluctuating environmental conditions, mainly intense irradiation, including ultraviolet radiation, and lack of water leading to desiccation. Therefore, green algae surviving in these environments must have evolved with either avoidance or protective strategies, as well as repair mechanisms for damage. In this review we have highlighted these mechanisms, which include photoprotection, photochemical quenching, and high osmotic values to avoid water loss, and in some groups flexibility of secondary cell walls to maintain turgor pressure even in water-limited situations. These highly specialized green algae will serve as good model organisms to study desiccation tolerance or photoprotective mechanisms, due to their natural capacity to withstand unfavorable conditions. We point out the urgent need for modern phylogenetic approaches in characterizing these organisms, and molecular methods for analyzing the metabolic changes involved in their adaptive strategies.
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Affiliation(s)
- Ulf Karsten
- Institute of Biological Sciences, Applied Ecology and Phycology, University of Rostock, Albert-Einstein-Strasse 3, 18059 Rostock, Germany
| | - Andreas Holzinger
- Functional Plant Biology, Institute of Botany, University of Innsbruck, Sternwartestraße 15, 6020 Innsbruck, Austria
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Holzinger A, Karsten U. Desiccation stress and tolerance in green algae: consequences for ultrastructure, physiological and molecular mechanisms. FRONTIERS IN PLANT SCIENCE 2013; 4:327. [PMID: 23986769 PMCID: PMC3749462 DOI: 10.3389/fpls.2013.00327] [Citation(s) in RCA: 132] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Accepted: 08/02/2013] [Indexed: 05/18/2023]
Abstract
Although most green algae typically occur in aquatic ecosystems, many species also live partly or permanently under aeroterrestrial conditions, where the cells are exposed to the atmosphere and hence regularly experience dehydration. The ability of algal cells to survive in an air-dried state is termed desiccation tolerance. The mechanisms involved in desiccation tolerance of green algae are still poorly understood, and hence the aim of this review is to summarize recent findings on the effects of desiccation and osmotic water loss. Starting from structural changes, physiological, and biochemical consequences of desiccation will be addressed in different green-algal lineages. The available data clearly indicate a range of strategies, which are rather different in streptophycean and non-streptophycean green algae. While members of the Trebouxiophyceae exhibit effective water loss-prevention mechanisms based on the biosynthesis and accumulation of particular organic osmolytes such as polyols, these compounds are so far not reported in representatives of the Streptophyta. In members of the Streptophyta such as Klebsormidium, the most striking observation is the appearance of cross-walls in desiccated samples, which are strongly undulating, suggesting a high degree of mechanical flexibility. This aids in maintaining structural integrity in the dried state and allows the cell to maintain turgor pressure for a prolonged period of time during the dehydration process. Physiological strategies in aeroterrestrial green algae generally include a rapid reduction of photosynthesis during desiccation, but also a rather quick recovery after rewetting, whereas aquatic species are sensitive to drying. The underlying mechanisms such as the affected molecular components of the photosynthetic machinery are poorly understood in green algae. Therefore, modern approaches based on transcriptomics, proteomics, and/or metabolomics are urgently needed to better understand the molecular mechanisms involved in desiccation-stress physiology of these organisms. The very limited existing information is described in the present review.
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Affiliation(s)
- Andreas Holzinger
- Functional Plant Biology, Institute of Botany, University of InnsbruckInnsbruck, Austria
| | - Ulf Karsten
- Applied Ecology and Phycology, Institute of Biological Sciences, University of RostockRostock, Germany
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Holzinger A, Karsten U. Desiccation stress and tolerance in green algae: consequences for ultrastructure, physiological and molecular mechanisms. FRONTIERS IN PLANT SCIENCE 2013. [PMID: 23986769 DOI: 10.3389/fpls.2013.0327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Although most green algae typically occur in aquatic ecosystems, many species also live partly or permanently under aeroterrestrial conditions, where the cells are exposed to the atmosphere and hence regularly experience dehydration. The ability of algal cells to survive in an air-dried state is termed desiccation tolerance. The mechanisms involved in desiccation tolerance of green algae are still poorly understood, and hence the aim of this review is to summarize recent findings on the effects of desiccation and osmotic water loss. Starting from structural changes, physiological, and biochemical consequences of desiccation will be addressed in different green-algal lineages. The available data clearly indicate a range of strategies, which are rather different in streptophycean and non-streptophycean green algae. While members of the Trebouxiophyceae exhibit effective water loss-prevention mechanisms based on the biosynthesis and accumulation of particular organic osmolytes such as polyols, these compounds are so far not reported in representatives of the Streptophyta. In members of the Streptophyta such as Klebsormidium, the most striking observation is the appearance of cross-walls in desiccated samples, which are strongly undulating, suggesting a high degree of mechanical flexibility. This aids in maintaining structural integrity in the dried state and allows the cell to maintain turgor pressure for a prolonged period of time during the dehydration process. Physiological strategies in aeroterrestrial green algae generally include a rapid reduction of photosynthesis during desiccation, but also a rather quick recovery after rewetting, whereas aquatic species are sensitive to drying. The underlying mechanisms such as the affected molecular components of the photosynthetic machinery are poorly understood in green algae. Therefore, modern approaches based on transcriptomics, proteomics, and/or metabolomics are urgently needed to better understand the molecular mechanisms involved in desiccation-stress physiology of these organisms. The very limited existing information is described in the present review.
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Affiliation(s)
- Andreas Holzinger
- Functional Plant Biology, Institute of Botany, University of Innsbruck Innsbruck, Austria
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