Ectocarpus

Summary

Ectocarpus is a genus of filamentous brown alga that is a model organism for the genomics of multicellularity.[1][2] Among possible model organisms in the brown algae, Ectocarpus was selected for the relatively small size of its mature thallus and the speed with which it completes its life cycle.[3][4] Tools available for Ectocarpus as a model species include a high quailty genome sequence[5] and both forward[6] and reverse genetic[7] methodologies, the latter based on CRISPR-Cas9.

Ectocarpus
E. siliculosus, from the Brockhaus and Efron Encyclopedic Dictionary (1890-1907)
Scientific classification Edit this classification
Domain: Eukaryota
Clade: Diaphoretickes
Clade: SAR
Clade: Stramenopiles
Phylum: Gyrista
Subphylum: Ochrophytina
Class: Phaeophyceae
Order: Ectocarpales
Family: Ectocarpaceae
Genus: Ectocarpus
Lyngbye 1819

Taxonomy and Nomenclature edit

Brown algae are heterokonts, a group that also includes diatoms and oomycetes. Despite their simple filamentous thalli, the Ectocarpales are part of the crown group of brown algal orders and are a sister group to the order Laminariales (kelps).[8] The type species for the genus is Ectocarpus siliculosus (Dillwyn) Lyngbye.[9] In 1809, Dillwyn described Ectocarpus as another algae known as Conferva siliculosa basing from collected specimens by W.J. Hooker from Norfolk and East Sussex. In 1819, Lyngbye subsequently described Ectocarpus using a specimen from Denmark, citing C. siliculosa Dilwyn as its basionym.[10]

Morphology edit

Studies on morphology have been limited for Ectocarpus as only two species in the genera (E. siliculosus and E. fasciculatus) are well-described based on morphology and genetic sequence.

Ectocarpus is a filamentous alga that can grow up to 30 cm. Cultured specimens in the laboratory tend to be fertile when they are 1–3 cm in length. Ectocarpus has a normal, branched appearance in unialgal cultures, but in axenic cultures it has a ball-shaped appearance suggesting that bacterial symbionts are required for the alga to attain normal morphology.[11]

Distribution edit

Ectocarpus can be found across the globe, in temperate shorelines growing as epiphytes on other flora (e.g. seagrass, other alga) or on rocky substrates (epilithic). While commonly attached to a substrate, thalli of Ectocarpus may also survive while floating. Ectocarpus are more commonly found as epiphytes on marine macroflora rather than epilithic.[12] E. fasciculatus is known as an endophyte of Laminaria digitata, but no study has documented how it bypasses the kelp's defense.[13][14]E. crouniorium are found in the intertidal zone while E. siliculosus and E. fasciculatus can be found in mid-intertidal and subtidal zones, respectively.[15]

Ecology edit

Ectocarpus thalli tend to shelter several marine invertebrates (e.g. crustaceans and nematodes) and some protists.[16] Temperature affects the life cycle of some strains, which may suggest genetic differences among Ectocarpus species.[17] A study of the life cycles of natural populations in NW France and SW Italy found marked isomorphy between generations in some populations and evidence of populations with modified, asexual life cycles.[18]

Life History edit

In the laboratory, the life history is an isomorphic to slightly heteromorphic alternation of generations, but asexual strains also exist. Ectocarpus has a haploid-diploid life cycle with both sporophyte and gametophyte generations. It can complete its whole life cycle within 3 months in the laboratory. Diploid sporophytes give rise to haploid meiospores which will then produce a haploid gametophyte generation. These gametophytes are dioecious, producing either male or female gametes, which fuse to produce diploid zygotes, restarting the sporophyte stage. Parthenogenesis may also occur when a gamete does not find a gamete of the opposite sex, producing a parthenosporophyte.[19] Deployment of the sporophyte developmental program requires two TALE homeodomain transcription factors, OUROBOROS and SAMSARA.[20] If either of the genes encoding these two proteins is disfunctional, the alga develops as a gametophyte.

Cultivation and Exploitation edit

A protocol has been established to culture Ectocarpus in the laboratory. Ectocarpus is able to grow in artificial seawater although the standard medium is Provasoli-enriched seawater (PES). Standard laboratory conditions are growth at 13 degrees Celsius under a 12h:12h light:dark cycle with irradiance at 20 µmol photons m−2 s−1.[21]

Chemical Composition edit

Iodide originating from seawater can accumulate to high concentrations in several brown algae but high levels are not observed in Ectocarpus. Genes predicted to encode enzymes involved in iodine metabolism have been identified in Ectocarpus, including haloperoxidases, dehalogenases and haloalkane dehalogenases.[22] These enzymes may be part of the defence mechanism of Ectocarpus against halogenated defenses of brown algal hosts when growing as an epiphyte.[23]

Utilization and Management edit

Ectocarpus is vulnerable to an array of pathogens and parasites and is also sensitive to abiotic stresses such as shifts in temperature, light and salinity. Major modifications to the Ectocarpus transcriptome have been observed following stress treatments.[24]

List of species edit

Some currently accepted species of Ectocarpus include:

  • Ectocarpus acanthophorus Kützing
  • Ectocarpus acutoramulis Noda
  • Ectocarpus acutus Setchell & N.L.Gardner
  • Ectocarpus adriaticus Ercegovic
  • Ectocarpus affinis Setchell & N.L.Gardner
  • Ectocarpus aleuticus Kützing
  • Ectocarpus auratus Bory de Saint-Vincentex Kützing
  • Ectocarpus balakrishnanii V.Krishnamurthy
  • Ectocarpus barbadensis Kuckuck
  • Ectocarpus berteroanus Montagne
  • Ectocarpus bombycinus Kützing
  • Ectocarpus borealis (Kjellman) Kjellman
  • Ectocarpus bracchiolus Lindauer
  • Ectocarpus brachiatus (Smith) S.F.Gray
  • Ectocarpus brevicellularis Noda
  • Ectocarpus caliacrae Celan
  • Ectocarpus capensis Kützing
  • Ectocarpus caspicus Henckel
  • Ectocarpus chantransioides Setchell & N.L.Gardner
  • Ectocarpus chapmanii Lindauer
  • Ectocarpus chnoosporae Børgesen
  • Ectocarpus cladosiphonae Noda
  • Ectocarpus clavifer J.Agardh
  • Ectocarpus commensalis Setchell & N.L.Gardner
  • Ectocarpus commixtus Noda
  • Ectocarpus confusiphyllus Noda
  • Ectocarpus congregatus Zanardini
  • Ectocarpus constanciae Hariot
  • Ectocarpus corticulatus De A.Saunders
  • Ectocarpus crouanii Thuret
  • Ectocarpus crouaniorum Thuret
  • Ectocarpus cryptophilus Børgesen
  • Ectocarpus cymosus Zanardini
  • Ectocarpus cystophylloides Noda
  • Ectocarpus dellowianus Lindauer
  • Ectocarpus denudatus P.L.Crouan & H.M.Crouan
  • Ectocarpus dictyoptericola Noda
  • Ectocarpus distortus Carmichael
  • Ectocarpus divergens Kornmann
  • Ectocarpus ensenadanus N.L.Gardner
  • Ectocarpus erectus Kützing
  • Ectocarpus exiguus Skottsberg
  • Ectocarpus exilis Zanardini
  • Ectocarpus falklandicus Skottsberg
  • Ectocarpus fasciculatus Harvey (syn: Ectocarpus Landsburgii Harvey; named after the rev. David Landsborough)[25]
  • Ectocarpus fenestroides P.L.Crouan & H.M.Crouan
  • Ectocarpus flagelliferus Setchell & N.L.Gardner
  • Ectocarpus flagelliformis Kützing
  • Ectocarpus fructuosus Setchell & N.L.Gardner
  • Ectocarpus fulvescens Schousboe ex Thuret
  • Ectocarpus fungiformis Oltmanns
  • Ectocarpus fusiformis Nagai
  • Ectocarpus giraudiae J.Agardh ex William M. Wilson
  • Ectocarpus glaziovii Zeller
  • Ectocarpus gonodioides Setchell & N.L.Gardner
  • Ectocarpus hamulosus Harvey & J.W.Bailey
  • Ectocarpus hancockii E.Y.Dawson
  • Ectocarpus heterocarpus P.L.Crouan & H.M.Crouan
  • Ectocarpus hornericola Noda
  • Ectocarpus humilis Kützing
  • Ectocarpus intermedius Kützing
  • Ectocarpus isopodicola E.Y.Dawson
  • Ectocarpus kellneri Meneghini
  • Ectocarpus kjellmanioides Noda
  • Ectocarpus laminariae Noda
  • Ectocarpus laurenciae Yamada
  • Ectocarpus lepasicola Noda
  • Ectocarpus macrocarpus Harvey
  • Ectocarpus macrocarpus P.L.Crouan & H.M.Crouan
  • Ectocarpus minor Noda
  • Ectocarpus minutissimus Skottsberg & Levring
  • Ectocarpus minutulus Montagne
  • Ectocarpus mitchellioides Noda
  • Ectocarpus monzensis Noda & Konno
  • Ectocarpus multifurcus Zanardini
  • Ectocarpus myurus Zanardini
  • Ectocarpus natans Zanardini
  • Ectocarpus niigatensis Noda
  • Ectocarpus nitens De Notaris
  • Ectocarpus oblongatus Noda
  • Ectocarpus obovatus Foslie
  • Ectocarpus obtusocarpus P.L.Crouan & H.M.Crouan
  • Ectocarpus obtusus Noda
  • Ectocarpus parvulus Kützing
  • Ectocarpus pectenis Ercegović
  • Ectocarpus penicillatus (C.Agardh) Kjellman
  • Ectocarpus plasticola Noda
  • Ectocarpus plumosus Noda
  • Ectocarpus polysiphoniae Noda
  • Ectocarpus pumilus Zanardini
  • Ectocarpus radicans Zanardini
  • Ectocarpus rallsiae Vickers
  • Ectocarpus ramentaceus Zanardini
  • Ectocarpus rotundatoapicalis Noda & Honda
  • Ectocarpus rudis Zanardini
  • Ectocarpus rufulus Kützing
  • Ectocarpus rufus (Roth) C.Agardh
  • Ectocarpus sadoensis Noda
  • Ectocarpus sargassicaulinus Noda
  • Ectocarpus sargassiphyllus Noda
  • Ectocarpus saxatilis Zanardini
  • Ectocarpus scytosiphonae Noda
  • Ectocarpus shiiyaensis Noda
  • Ectocarpus shimokitaensis Ohta
  • Ectocarpus siliculosus (Dillwyn) Lyngbye
  • Ectocarpus simpliciusculus C.Agardh
  • Ectocarpus simulans Setchell & N.L.Gardner
  • Ectocarpus sonorensis E.Y.Dawson
  • Ectocarpus sphaericus Ohta
  • Ectocarpus strigosus Zanardini
  • Ectocarpus tamarinii Børgesen
  • Ectocarpus taoniae Setchell & N.L.Gardner
  • Ectocarpus tappiensis Ohta
  • Ectocarpus tasshaensis Noda
  • Ectocarpus trichophorus H.Gran
  • Ectocarpus tsugaruensis Ohta
  • Ectocarpus variabilis Vickers
  • Ectocarpus venetus Kützing
  • Ectocarpus vungtauensis P.H. Hô
  • Ectocarpus yezoensis Yamada & Tanaka
  • Ectocarpus zonariae W.R.Taylor
  • Ectocarpus zosterae Noda & Ohta

References edit

  1. ^ Cock, J.M.; et al. (2010). "The Ectocarpus genome and the independent evolution of multicellularity in brown algae". Nature. 465 (7298): 617–621. Bibcode:2010Natur.465..617C. doi:10.1038/nature09016. PMID 20520714.
  2. ^ Cock, J. Mark (2023). "The model system Ectocarpus: integrating functional genomics into brown algal research". Journal of Phycology. 59: 4–8. doi:10.1111/jpy.13310.
  3. ^ Peters, A.F.; Marie, D.; Scornet, D.; Kloareg, B.; Cock, J.M. (2004). "Proposal of Ectocarpus siliculosus (Ectocarpales, Phaeophyceae) as a model organism for brown algal genetics and genomics". Journal of Phycology. 40 (6): 1079–1088. doi:10.1111/j.1529-8817.2004.04058.x. S2CID 86664046.
  4. ^ Dieter G. Müller, Markus Kapp, Rolf Knippers, Viruses in Marine Brown Algae, In: Karl Maramorosch, Frederick A. Murphy and Aaron J. Shatkin, Editor(s), Advances in Virus Research, Academic Press, 1998, Volume 50, Pages 49-67, ISSN 0065-3527, ISBN 9780120398508, doi:10.1016/S0065-3527(08)60805-2
  5. ^ Cormier, Alexandre; Avia, Komlan; Sterck, Lieven; Derrien, Thomas; Wucher, Valentin; Andres, Gwendoline; Monsoor, Misharl; Godfroy, Olivier; Lipinska, Agnieszka; Perrineau, Marie‐Mathilde; Van De Peer, Yves; Hitte, Christophe; Corre, Erwan; Coelho, Susana M.; Cock, J. Mark (2016-11-21). "Re‐annotation, improved large‐scale assembly and establishment of a catalogue of noncoding loci for the genome of the model brown alga Ectocarpus". New Phytologist. 214 (1). Wiley: 219–232. doi:10.1111/nph.14321. ISSN 0028-646X.
  6. ^ Macaisne, Nicolas; Liu, Fuli; Scornet, Delphine; Peters, Akira F.; Lipinska, Agnieszka; Perrineau, Marie-Mathilde; Henry, Antoine; Strittmatter, Martina; Coelho, Susana M.; Cock, J. Mark (2017-01-01). "TheEctocarpus IMMEDIATE UPRIGHTgene encodes a member of a novel family of cysteine-rich proteins that have an unusual distribution across the eukaryotes". Development. The Company of Biologists. doi:10.1242/dev.141523. ISSN 1477-9129.
  7. ^ Badis, Yacine; Scornet, Delphine; Harada, Minori; Caillard, Céline; Godfroy, Olivier; Raphalen, Morgane; Gachon, Claire M. M.; Coelho, Susana M.; Motomura, Taizo; Nagasato, Chikako; Cock, J. Mark (2021-07-10). "Targeted CRISPR‐Cas9‐based gene knockouts in the model brown alga Ectocarpus". New Phytologist. 231 (5). Wiley: 2077–2091. doi:10.1111/nph.17525. ISSN 0028-646X.
  8. ^ Akita, Shingo; Vieira, Christophe; Hanyuda, Takeaki; Rousseau, Florence; Cruaud, Corinne; Couloux, Arnaud; Heesch, Svenja; Cock, J. Mark; Kawai, Hiroshi (2022). "Providing a phylogenetic framework for trait-based analyses in brown algae: Phylogenomic tree inferred from 32 nuclear protein-coding sequences". Molecular Phylogenetics and Evolution. 168: 107408. doi:10.1016/j.ympev.2022.107408.
  9. ^ AlgaeBase
  10. ^ Charrier, Bénédicte; Coelho, Susana M.; Bail, Aude Le; Tonon, Thierry; Michel, Gurvan; Potin, Philippe; Kloareg, Bernard; Boyen, Catherine; Peters, Akira F.; Cock, J. Mark (2008). "Development and physiology of the brown alga Ectocarpus siliculosus: two centuries of research". New Phytologist. 177 (2): 319–332. doi:10.1111/j.1469-8137.2007.02304.x. ISSN 1469-8137. PMID 18181960.
  11. ^ Tapia, Javier E.; González, Bernardo; Goulitquer, Sophie; Potin, Philippe; Correa, Juan A. (2016). "Microbiota Influences Morphology and Reproduction of the Brown Alga Ectocarpus sp". Frontiers in Microbiology. 7: 197. doi:10.3389/fmicb.2016.00197. ISSN 1664-302X. PMC 4765120. PMID 26941722.
  12. ^ Charrier, Bénédicte; Coelho, Susana M.; Bail, Aude Le; Tonon, Thierry; Michel, Gurvan; Potin, Philippe; Kloareg, Bernard; Boyen, Catherine; Peters, Akira F.; Cock, J. Mark (2008). "Development and physiology of the brown alga Ectocarpus siliculosus: two centuries of research". New Phytologist. 177 (2): 319–332. doi:10.1111/j.1469-8137.2007.02304.x. ISSN 1469-8137. PMID 18181960.
  13. ^ Russell (1983). "Parallel growth patterns in algal epiphytes and Laminaria blades" (PDF). Marine Ecology Progress Series. 13: 303. Bibcode:1983MEPS...13..303R. doi:10.3354/meps013303.
  14. ^ Russell (1983). "Formation of an ectocarpoid epiflora on blades of Laminaria digitata" (PDF). Marine Ecology Progress Series. 11: 181. Bibcode:1983MEPS...11..181R. doi:10.3354/meps011181.
  15. ^ Peters, Akira F.; Wijk, Serinde J. Van; Cho, Ga Youn; Scornet, Delphine; Hanyuda, Takeaki; Kawai, Hiroshi; Schroeder, Declan C.; Cock, J. Mark; Boo, Sung Min (2010). "Reinstatement of Ectocarpus crouaniorum Thuret in Le Jolis as a third common species of Ectocarpus (Ectocarpales, Phaeophyceae) in Western Europe, and its phenology at Roscoff, Brittany". Phycological Research. 58 (3): 157–170. doi:10.1111/j.1440-1835.2010.00574.x. ISSN 1440-1835. S2CID 82731900.
  16. ^ Charrier, Bénédicte; Coelho, Susana M.; Bail, Aude Le; Tonon, Thierry; Michel, Gurvan; Potin, Philippe; Kloareg, Bernard; Boyen, Catherine; Peters, Akira F.; Cock, J. Mark (2008). "Development and physiology of the brown alga Ectocarpus siliculosus: two centuries of research". New Phytologist. 177 (2): 319–332. doi:10.1111/j.1469-8137.2007.02304.x. ISSN 1469-8137. PMID 18181960.
  17. ^ Bolton, J. J. (1983-03-01). "Ecoclinal variation in Ectocarpus siliculosus (Phaeophyceae) with respect to temperature growth optima and survival limits". Marine Biology. 73 (2): 131–138. doi:10.1007/BF00406880. ISSN 1432-1793. S2CID 85006513.
  18. ^ Couceiro, Lucía; Le Gac, Mickael; Hunsperger, Heather M.; Mauger, Stéphane; Destombe, Christophe; Cock, J. Mark; Ahmed, Sophia; Coelho, Susana M.; Valero, Myriam; Peters, Akira F. (2015). "Evolution and maintenance of haploid-diploid life cycles in natural populations: The case of the marine brown algaEctocarpus". Evolution. 69 (7). Wiley: 1808–1822. doi:10.1111/evo.12702. ISSN 0014-3820.
  19. ^ Charrier, Bénédicte; Coelho, Susana M.; Le Bail, Aude; Tonon, Thierry; Michel, Gurvan; Potin, Philippe; Kloareg, Bernard; Boyen, Catherine; Peters, Akira F.; Cock, J. Mark (January 2008). "Development and physiology of the brown alga Ectocarpus siliculosus : two centuries of research". New Phytologist. 177 (2): 319–332. doi:10.1111/j.1469-8137.2007.02304.x. ISSN 0028-646X. PMID 18181960.
  20. ^ Arun, Alok; Coelho, Susana M.; Peters, Akira F.; Bourdareau, Simon; Pérès, Laurent; Scornet, Delphine; Strittmatter, Martina; Lipinska, Agnieszka; Yao, Haiqin; Godfroy, Olivier; Montecinos, Gabriel J.; Avia, Komlan; Macaisne, Nicolas; Troadec, Christelle; Bendahmane, Abdelhafid; Cock, J. Mark (2019). "Convergent recruitment of TALE homeodomain life cycle regulators to direct sporophyte development in land plants and brown algae". eLife. 8: e43101. doi:10.7554/eLife.43101.
  21. ^ Coelho, Susana M.; Scornet, Delphine; Rousvoal, Sylvie; Peters, Nick T.; Dartevelle, Laurence; Peters, Akira F.; Cock, J. Mark (2012-02-01). "How to Cultivate Ectocarpus". Cold Spring Harbor Protocols. 2012 (2): 258–261. doi:10.1101/pdb.prot067934. ISSN 1940-3402. PMID 22301662.
  22. ^ Cock, J. Mark; Sterck, Lieven; Rouzé, Pierre; Scornet, Delphine; Allen, Andrew E.; Amoutzias, Grigoris; Anthouard, Veronique; Artiguenave, François; Aury, Jean-Marc; Badger, Jonathan H.; Beszteri, Bank (June 2010). "The Ectocarpus genome and the independent evolution of multicellularity in brown algae". Nature. 465 (7298): 617–621. Bibcode:2010Natur.465..617C. doi:10.1038/nature09016. ISSN 1476-4687. PMID 20520714. S2CID 4329490.
  23. ^ Coelho, Susana M.; Scornet, Delphine; Rousvoal, Sylvie; Peters, Nick T.; Dartevelle, Laurence; Peters, Akira F.; Cock, J. Mark (2012-02-01). "Ectocarpus: A Model Organism for the Brown Algae". Cold Spring Harbor Protocols. 2012 (2): 193–198. doi:10.1101/pdb.emo065821. ISSN 1940-3402. PMID 22301644.
  24. ^ Dittami, Simon M.; Gravot, Antoine; Renault, David; Goulitquer, Sophie; Eggert, Anja; Bouchereau, Alain; Boyen, Catherine; Tonon, Thierry (2011). "Integrative analysis of metabolite and transcript abundance during the short-term response to saline and oxidative stress in the brown alga Ectocarpus siliculosus". Plant, Cell & Environment. 34 (4): 629–642. doi:10.1111/j.1365-3040.2010.02268.x. ISSN 1365-3040. PMID 21281312.
  25. ^ For information concerning Ectocarpus landsburgii and link to download of the original description (with image) in Harvey, W.H. (1849)—Phycologia britannica see: "Ectocarpus landsburgii Harvey 1849". AlgaeBase. Archived from the original on 2022-11-21. Retrieved 2022-11-21.

Further reading edit

Bourdareau, Simon; Tirichine, Leila; Lombard, Bérangère; Loew, Damarys; Scornet, Delphine; Wu, Yue; Coelho, Susana M.; Cock, J. Mark (2021). "Histone modifications during the life cycle of the brown alga Ectocarpus". Genome Biology. 22 (1). Springer Science and Business Media LLC. doi:10.1186/s13059-020-02216-8. ISSN 1474-760X.

Ahmed, Sophia; Cock, J. Mark; Pessia, Eugenie (2014). "A Haploid System of Sex Determination in the Brown Alga Ectocarpus sp". Current Biology. 24 (17): 1945–1957. doi:10.1016/j.cub.2014.07.042. PMID 25176635.

Tarver, James E.; Cormier, Alexandre; Pinzón, Natalia; Taylor, Richard S.; Carré, Wilfrid; Strittmatter, Martina; Seitz, Hervé; Coelho, Susana M.; Cock, J. Mark (2015). "microRNAs and the evolution of complex multicellularity: identification of a large, diverse complement of microRNAs in the brown algaEctocarpus". Nucleic Acids Research. 43 (13). Oxford University Press (OUP): 6384–6398. doi:10.1093/nar/gkv578. ISSN 0305-1048.

Prigent, Sylvian (2014). "The genome-scale metabolic network of Ectocarpus siliculosus (EctoGEM): a resource to study brown algal physiology and beyond". Plant Journal. 80 (2): 367–381. doi:10.1111/tpj.12627. PMID 25065645.

External links edit

  • Ectocarpus on algaebase.org