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Satoshi Shimada - One of the best experts on this subject based on the ideXlab platform.
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ISOLATION AND TEMPORAL EXPRESSION ANALYSIS OF FRESHWATER-INDUCED GENES IN ULVA LIMNETICA (Ulvales, CHLOROPHYTA)(1).
Journal of Phycology, 2011Co-Authors: Kensuke Ichihara, Frédéric Mineur, Satoshi ShimadaAbstract:The macroalga Ulva limnetica K. Ichihara et S. Shimada is the only known Ulva species to be distributed exclusively in freshwater and is restricted to freshwater bodies in the Ryuku archipelago. Molecular phylogenetic analysis suggests that U. limnetica originally evolved from marine forms of Ulva. The mechanisms of adaptation to freshwater in Ulva spp. are poorly understood. In this study, we isolated genes potentially involved in adaptation or tolerance to freshwater conditions in U. limnetica, using suppression subtractive hybridization between mRNAs of samples cultured in freshwater and seawater conditions. A total of 219 genes, up-regulated by the exposure of the macroalga to freshwater, were isolated. Reverse transcription–PCR (RT–PCR) revealed 39 clones, including malate dehydrogenase, soluble starch synthase, triosephosphate isomerase, plastid ribosomal protein, DnaJ-like protein, and chloroplast ascorbate peroxidase (APX), which were specifically or preferentially expressed in freshwater conditions. These 39 clones were also analyzed for their temporal transcriptional response to freshwater conditions. A large majority of these up-regulated genes showed a transient peak of expression after 1–4 h, followed in the next 24 h by a decrease to a stable level (over the 7 d of the experiment). After the initial response peak, the level of expression either remained higher than in the control (long-term response) or returned to a level similar to pretreatment level. A few genes showed a more delayed response (i.e., after several days) to freshwater exposure. Finally, we discussed the possible contributions of the freshwater-induced genes in the acquisition of freshwater adaptation or tolerance of U. limnetica.
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phylogeographic analysis of the genus ulva Ulvales chlorophyta including bloom sample in qingdao china
2010Co-Authors: Satoshi Shimada, Frédéric Mineur, Kensuke Ichihara, Masanori Hiraoka, Moe Nagano, Wenrong Zhu, Usa MarineAbstract:In June 2008, news agencies worldwide reported a ‘green tide’ phenomenon that was threatening the upcoming Olympic sailing events in Qingdao, China. This was caused by the green macroalgal genus Ulva. Previous work showed that the species involved in this phenomenon belongs to a complex of tubular species called the LPP complex clade (i.e. including the species U. linza Linnaeus, U. prolifera O.F. Muller and U. procera (K. Ahlner) Hayden et al.). To understand the relationship between the bloom formed in open water and the attached populations of Ulva found on the shorelines surrounding Qingdao, we performed some phylogenetic analyses based on the Internal Transcribed Spacer (ITS) region of the nuclear rDNA, on a larger set of samples. Due to a lack of resolution of this marker at the intraspecific level, we performed some new analyses based on the spacer region between tandemly repeated 5S rDNA. Samples were divided into two groups: the U. linza group, which includes unbranched foliose thalli collected from marine environment; and the U. prolifera group, which includes unbranched folious and well-branched tubular thalli from both seas (including Qingdao samples) and rivers. The bloom samples and a part of the attached samples had identical sequences for the 5S rDNA spacer region. ML tree and statistical parsimony network (SPN) tree indicated that they were closely related with populations from the Sea of Japan. Other attached samples of the Qingdao area possessed identical sequence to samples widely distributed on the Pacific coast of Japan, from Okinawa to the Kanto area.
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New species of freshwater Ulva, Ulva limnetica (Ulvales, Ulvophyceae) from the Ryukyu Islands, Japan
Phycological Research, 2009Co-Authors: Kensuke Ichihara, Masanori Hiraoka, Shogo Arai, Masayuki Uchimura, Hiroki Ebata, Satoshi ShimadaAbstract:SUMMARY Ulva limnetica Ichihara et Shimada, sp. nov. (Ulvales,Ulvophyceae) is described from the Ryukyu Islands,Japan, and is characterized by thalli that are: (i)branched, tubular, fragile and wrinkled; (ii) up to 80 cmin height and up to 2 cm in diameter; (iii) light toyellowish green in color; and (iv) having an asexualreproduction by means of quadriflagellate swarmers.Rhizoidal cells bear tubular extensions on the outsideof the cell layer in the stipe. Ulva limnetica is distin-guished from species with similar thalli by chloroplastdisposition, branching pattern, number of pyrenoidsper cell and gross morphology. It is also distinguishedby sequences of the nuclear-encoded 18S ribosomalRNA gene, internal transcribed spacer 2 region andthe plastid-encoded large subunit of ribulose-1,5-bisphosphate carboxylase/oxgenase gene ( rbc L). Ulvalimnetica was clustered with other Ulva species in anearly diverging lineage within the genus.Key words: molecular phylogeny, morphology, rbc L,taxonomy,
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first record of ulva pertusa kjellman Ulvales chlorophyta in the pacific coast of mexico
Algae, 2008Co-Authors: Racal Aguilarrosasl, Luis E Aguilarrosas, Satoshi ShimadaAbstract:Based on samplings during 2006-2007 on the intertidal zone of Playa Tampico, Erendira and Punta Baja, Baja California, Ulva pertusa Kjellman (Ulvales, Chlorophyta) was recorded for the first time for the Pacific coast of Mexico. An alga native to Asia, U. pertusa has just recently been recorded in the southern coast of California (USA). The identification of U. pertusa was based on the observation of the morphology and reproductive characters of the collected specimens. Furthermore, the species identity was confirmed by molecular comparison between nuclearencoded ITS2 sequences of the Mexican samples and those of other Ulva species in GenBnak data. Habitat and distribution of U. pertusa along the Pacific coast of North America are also described. Considering our new report of its occurrence in Mexico, we conclude that U. pertusa is expanding its geographical distribution by trans-ocean introductions.ᔌ渀㔲〮㘻Ԁ䭃䑎䷗᜕ఄ5㈰⸵㬅K䍄乍쀗ጊЀ㔲〻Ԁ䭃䑎䴀
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Species Diversity and Seasonal Changes of Dominant Ulva Species (Ulvales, Ulvophyceae) in Mikawa Bay, Japan, Deduced from ITS2 rDNA Region Sequences
ALGAE, 2007Co-Authors: Hiroshi Kawai, Satoshi Shimada, Takeaki Hanyuda, Teruaki Suzuki, Gamagori City OfficeAbstract:Frequent occurrences of green tides caused by Ulva species (Ulvales, Ulvophyceae) associated with eutrophication along enclosed coasts are currently causing environmental problems in coastal ecosystems. In addition, increasing intercontinental introductions of coastal marine organisms, including Ulva, are also a serious issue. However, due to the considerable morphological plasticity of this genus, the taxonomy of Ulva species based on morphological studies is problematic. Therefore, in order to elucidate the species diversity and seasonal changes of the dominant Ulva species in Mikawa Bay, central Honshu, Japan, we made seasonal collections of Ulva species at seven localities, and identified the dominant species using the ITS2 rDNA region sequences. We identified the following nine taxa as common Ulva species in the area: 1) Ulva pertusa Kjellman; 2) U. ohnoi Hiraoka et Shimada; 3) U. linza L.; 4) U. californica Wille; 5) U. flexuosa Wulfen; 6) U. fasciata Delile; 7) U. compressa L.; 8) U. armoricana Dion et al.; 9) U. scandinavica Bliding. Among the species, U. pertusa was most common and dominant from spring to summer, and U. ohnoi from autumn to winter. Ulva californica and U. scandinavica have not been reported before from Japan.
Masanori Hiraoka - One of the best experts on this subject based on the ideXlab platform.
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phylogeographic analysis of the genus ulva Ulvales chlorophyta including bloom sample in qingdao china
2010Co-Authors: Satoshi Shimada, Frédéric Mineur, Kensuke Ichihara, Masanori Hiraoka, Moe Nagano, Wenrong Zhu, Usa MarineAbstract:In June 2008, news agencies worldwide reported a ‘green tide’ phenomenon that was threatening the upcoming Olympic sailing events in Qingdao, China. This was caused by the green macroalgal genus Ulva. Previous work showed that the species involved in this phenomenon belongs to a complex of tubular species called the LPP complex clade (i.e. including the species U. linza Linnaeus, U. prolifera O.F. Muller and U. procera (K. Ahlner) Hayden et al.). To understand the relationship between the bloom formed in open water and the attached populations of Ulva found on the shorelines surrounding Qingdao, we performed some phylogenetic analyses based on the Internal Transcribed Spacer (ITS) region of the nuclear rDNA, on a larger set of samples. Due to a lack of resolution of this marker at the intraspecific level, we performed some new analyses based on the spacer region between tandemly repeated 5S rDNA. Samples were divided into two groups: the U. linza group, which includes unbranched foliose thalli collected from marine environment; and the U. prolifera group, which includes unbranched folious and well-branched tubular thalli from both seas (including Qingdao samples) and rivers. The bloom samples and a part of the attached samples had identical sequences for the 5S rDNA spacer region. ML tree and statistical parsimony network (SPN) tree indicated that they were closely related with populations from the Sea of Japan. Other attached samples of the Qingdao area possessed identical sequence to samples widely distributed on the Pacific coast of Japan, from Okinawa to the Kanto area.
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identification of cryptic ulva species chlorophyta Ulvales transported by ballast water
Journal of Biological Research, 2010Co-Authors: Maria Monia Flagella, Masanori Hiraoka, Nikos Andreakis, Marc Verlaque, Maria Cristina Buia, Stazione ZoologicaAbstract:Ballast waters of ships coming from Egyptian (Port Said) and Lebanese (Beirut) harbours have been collected in the West Mediterranean harbour of Naples (Italy). Samples have been cultured for one month in order to identify seaweed species by means of morphological characters and molecular markers. At the morphological level, two Ulva species have been recognized. At the molecular level, the same isolates have been identified as Ulva ohnoi Hiraoka et Shimada, a green-tide-forming alga described from Japan, and Ulva fasciata Delile, a species described from the eastern Mediterranean (Egypt) and reported from all tropical and warm temperate seas. Since U. ohnoi has never been reported from the Mediterranean coasts before, crossing tests were performed between Mediterranean and Japanese isolates corroborating results obtained by molecular markers. In light of these findings, the role of ballast water in the introduction and secondary dispersal of marine macrophytes over long distances is discussed.
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New species of freshwater Ulva, Ulva limnetica (Ulvales, Ulvophyceae) from the Ryukyu Islands, Japan
Phycological Research, 2009Co-Authors: Kensuke Ichihara, Masanori Hiraoka, Shogo Arai, Masayuki Uchimura, Hiroki Ebata, Satoshi ShimadaAbstract:SUMMARY Ulva limnetica Ichihara et Shimada, sp. nov. (Ulvales,Ulvophyceae) is described from the Ryukyu Islands,Japan, and is characterized by thalli that are: (i)branched, tubular, fragile and wrinkled; (ii) up to 80 cmin height and up to 2 cm in diameter; (iii) light toyellowish green in color; and (iv) having an asexualreproduction by means of quadriflagellate swarmers.Rhizoidal cells bear tubular extensions on the outsideof the cell layer in the stipe. Ulva limnetica is distin-guished from species with similar thalli by chloroplastdisposition, branching pattern, number of pyrenoidsper cell and gross morphology. It is also distinguishedby sequences of the nuclear-encoded 18S ribosomalRNA gene, internal transcribed spacer 2 region andthe plastid-encoded large subunit of ribulose-1,5-bisphosphate carboxylase/oxgenase gene ( rbc L). Ulvalimnetica was clustered with other Ulva species in anearly diverging lineage within the genus.Key words: molecular phylogeny, morphology, rbc L,taxonomy,
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taxonomic and ecological profile of green tide species of ulva Ulvales chlorophyta in central philippines
Hydrobiologia, 2004Co-Authors: Danilo B Largo, Masanori Hiraoka, Jose Sembrano, Masao OhnoAbstract:Ulva spp. are common in the intertidal zones of the Philippines, but, at certain times, could over-proliferate producing blooms or `green tide' in some protected bays. In Mactan Island (Cebu), central Philippines, at least two species constitute the Ulva population, either as free-living or attached form. The one referred to in the literature as `Ulva lactuca' mainly consists of free-living population while the species referred to as Ulva reticulata consists mainly of attached population. Based on morphological and physiological characteristics, `U. lactuca' differs much from the descriptions of the species from its type locality in Europe in having a crumpled texture of blade, presence of tooth-like protuberances at the margins, thinner thallus (40–50 μm) and more pyrenoids per cell (two to four). The species referred to as `U. lactuca' in the Philippines therefore is a different species. Two morphotypes consisted the `U. lactuca' population from Mactan – a thick thallus and a thin thallus type. However, both morphotypes cultured under the same condition in the laboratory could transform into the same thin-thallus type observed in the field. `Green tide' caused by `U. lactuca' occur almost regularly in Station 1 of Mactan Island, reaching an average biomass of up to 2.6 kg wet wt m−2 (or 0.5 kg dry wt m−2). Ulva reticulata, although was less abundant in the rocky tidal zone at most times, reaching an average biomass of only up to 0.15 kg wet wt m−2 (or 0.03 kg dry wt m−2) had caused green tide in Station 2 around February–March. Reproductive structures were not observed in both Ulva species during the survey period suggesting that vegetative fragmentation is the main mode of propagation. Vegetative tissues excised from the thallus can be induced to release biflagellated large and small zooids.
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different life histories of enteromorpha prolifera Ulvales chlorophyta from four rivers on shikoku island japan
Phycologia, 2003Co-Authors: Masanori Hiraoka, Satoshi Shimada, Akinori Dan, Masaru Hagihira, Masao Migita, Masao OhnoAbstract:Populations of Enteromorpha prolifera collected from four rivers on Shikoku Island in Japan had three different types of life history. One type was the typical sexual life history of Enteromorpha, ...
Marc Lahaye - One of the best experts on this subject based on the ideXlab platform.
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determination of the chemical composition of ulvan a cell wall polysaccharide from ulva spp Ulvales chlorophyta by ft ir and chemometrics
Journal of Applied Phycology, 2009Co-Authors: Yannick Lerat, Annie Robic, Jean-francois Sassi, Dominique Bertrand, Marc LahayeAbstract:The water-soluble cell wall polysaccharides from green seaweeds of Ulva spp. (Ulvales, Chlorophyta), referred to as ulvan, demonstrate composition- and structure-related functional properties. Mid-infrared spectroscopy combined with chemometric techniques was investigated as a means to rapidly predict the chemical composition of ulvan extracts. A calibration was realized with 41 ulvan extracts from two Ulva species. The variables studied included the constituent sugars (rhamnose, xylose, glucose, galactose, glucuronic acid, iduronic acid), protein, and sulfate contents. The correlation between Fourier transform infrared and chemical data was developed using partial least squares (PLS) regression with full cross-validation (leave one out). The coefficients of determination in cross-validation (\(R_{{\text{CAL}}}^2 \)) and the standard error in cross-validation were determined for each variable. The PLS model validation resulted in a coefficient of determination (\(R_{{\text{VAL}}}^2 \)) and a standard error in prediction. Good predictions were obtained for rhamnose (\(R_{{\text{VAL}}}^2 \) = 0.9244), xylose (\(R_{{\text{VAL}}}^2 \) = 0.8758), glucuronic acid (\(R_{{\text{VAL}}}^2 \) = 0.9415), and sulfate (\(R_{{\text{VAL}}}^2 \) = 0.9218), which are the main ulvan constituents. However, minor components such as proteins, glucose, galactose, and iduronic acid were not correctly predicted. This study showed that mid-infrared spectroscopy combined with PLS regression is a reliable and fast method for the quantification of the main chemical constituents of ulvan extracts.
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Chemical composition and 13C NMR spectroscopic characterisation of ulvans from Ulva (Ulvales, Chlorophyta)
Journal of Applied Phycology, 1999Co-Authors: Marc Lahaye, Enrique Alvarez-cabal Cimadevilla, Ralph Kuhlenkamp, Bernard Quemener, Vincent Lognoné, Patrick DionAbstract:The chemical composition and structures of several ulvan extracts isolated from various Ulva species were studied. They were all composed mainly of rhamnose, glucuronic acid, xylose, glucose and sulphate with smaller amounts of iduronic acid and traces of galactose. Proteins were also present, most likely as contaminants. Precise quantification of the uronic acid content by chemical-enzymatic hydrolysis coupled to HPAEC-PAD analysis and by colorimetry was not achieved, most likely due to the incomplete hydrolysis of glucuronan segments, inadequate HPAEC-pulsed-amperometric response factor for iduronic acid and to a possible differential colorimetric response of the two uronic acids. ^13C NMR spectroscopic investigation of different ulvans demonstrated that they were all based on ulvanobiuronic acid 3-sulphate A and B repeating units [β-D-Glc pA-(1->4)-α-L-Rhap3S and α-L-IdopA-(1->4)-α-L-Rha p3S, respectively] as well as contiguous β 1->4 linked D-glucuronic acids possibly occurring either in ulvan or as a separate glucuronan. Marked variations in the content of the repeating structures were seen among the different samples. However, due to the limited number of samples studied, no conclusion was reached concerning the effects of species and ecophysiological conditions on the chemistry of ulvan.
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chemical characterisation and gelling properties of cell wall polysaccharides from species of ulva Ulvales chlorophyta
Hydrobiologia, 1996Co-Authors: Marc Lahaye, Bernard Quemener, Bimalendu Ray, Stephanie Baumberger, Monique A V AxelosAbstract:Two alkali-soluble polysaccharide fractions from the cell wall of Ulva ‘rigida’ were determined to be β-1,4-linked glucoxylans and a β–1,4-linked glucuronan by chemical and NMR spectroscopic analysis. The 13C NMR spectrum of water-soluble xyloglucuronorhamnan sulfate from Ulva ‘rigida’ referred to as ulvan is reported and the 13C and 1H NMR chemical shifts of its major repeating unit, the aldobiuronic acid β-D-GlcA-(1,4)-L-Rha, are given. The composition and gelling properties of ulvan from Ulva species from ‘green tides’ are also reported. The thermoreversible gel required both calcium and borate ions and the shear storage modulus G’ was ion concentration dependent. The mechanism of gelation and the associations of the different Ulva cell wall soluble polysaccharides are discussed.
Accioly, Miguel Da Costa - One of the best experts on this subject based on the ideXlab platform.
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Clorofíceas marinhas bentônicas da Praia de Serrambi, Pernambuco, Brasil
Sociedade Botânica do Brasil, 1998Co-Authors: Pereira, Sônia Maria Barreto, Accioly, Miguel Da CostaAbstract:É apresentado o levantamento florístico sobre as clorofíceas marinhas bentônicas encontradas na Praia de Serrambi, litoral Sul do Estado de Pernambuco. O material estudado foi coletado em três estações, as quais foram visitadas mensalmente durante o período de abril de 1986 a setembro de 1987. As clorofíceas foram representadas na flora local por 39 espécies, três variedades e uma forma, pertencentes às ordens Ulotrichales, Ulvales, Siphonocladales, Cladophorales, Caulerpales e Dasycladales. Acetabularia calyculus Quoy & Gaimard. In Freycinet, Bryopsis pennata Lamouroux, Bryopsis plumosa (Hudson) C. Agardh, Caulerpa ambigua Okamura, Caulerpa serrulata (Forsskål) J. Agardh emend Børgesen, Chaetomorpha brachygona Harvey, Cladophora coelothrix Kützing, Cladophoropsis membranacea (C. Agardh) Børgesen, Codium intertextum Collins & Hervey, Ernodesmis verticillata (Kützing) Børgesen são novas referências para a flora do litoral de Pernambuco. Pringsheimiella scutata (Reinke) von Höhnel ex Marchewianka o é também para o litoral continental do Brasil. Halimeda opuntia (L.) Lamouroux foi hospedeira de maior número de epífitas, enquanto Bryopsis plumosa, quando epífita, foi a que cresceu sobre maior número de hospedeiros
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Acta Botanica Brasilica
Sociedade Botânica do Brasil, 1998Co-Authors: Pereira, Sônia Maria Barreto, Accioly, Miguel Da CostaAbstract:p.25-51É apresentado o levantamento florístico sobre as clorofíceas marinhas bentônicas encontradas na Praia de Serrambi, litoral Sul do Estado de Pernambuco. O material estudado foi coletado em três estações, as quais foram visitadas mensalmente durante o período de abril de 1986 a setembro de 1987. As clorofíceas foram representadas na flora local por 39 espécies, três variedades e uma forma, pertencentes às ordens Ulotrichales, Ulvales, Siphonocladales, Cladophorales, Caulerpales e Dasycladales. Acetabularia calyculus Quoy & Gaimard. In Freycinet, Bryopsis pennata Lamouroux, Bryopsis plumosa (Hudson) C. Agardh, Caulerpa ambigua Okamura, Caulerpa serrulata (Forsskål) J. Agardh emend Børgesen, Chaetomorpha brachygona Harvey, Cladophora coelothrix Kützing, Cladophoropsis membranacea (C. Agardh) Børgesen, Codium intertextum Collins & Hervey, Ernodesmis verticillata (Kützing) Børgesen são novas referências para a flora do litoral de Pernambuco. Pringsheimiella scutata (Reinke) von Höhnel ex Marchewianka o é também para o litoral continental do Brasil. Halimeda opuntia (L.) Lamouroux foi hospedeira de maior número de epífitas, enquanto Bryopsis plumosa, quando epífita, foi a que cresceu sobre maior número de hospedeiros
Masao Ohno - One of the best experts on this subject based on the ideXlab platform.
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taxonomic and ecological profile of green tide species of ulva Ulvales chlorophyta in central philippines
Hydrobiologia, 2004Co-Authors: Danilo B Largo, Masanori Hiraoka, Jose Sembrano, Masao OhnoAbstract:Ulva spp. are common in the intertidal zones of the Philippines, but, at certain times, could over-proliferate producing blooms or `green tide' in some protected bays. In Mactan Island (Cebu), central Philippines, at least two species constitute the Ulva population, either as free-living or attached form. The one referred to in the literature as `Ulva lactuca' mainly consists of free-living population while the species referred to as Ulva reticulata consists mainly of attached population. Based on morphological and physiological characteristics, `U. lactuca' differs much from the descriptions of the species from its type locality in Europe in having a crumpled texture of blade, presence of tooth-like protuberances at the margins, thinner thallus (40–50 μm) and more pyrenoids per cell (two to four). The species referred to as `U. lactuca' in the Philippines therefore is a different species. Two morphotypes consisted the `U. lactuca' population from Mactan – a thick thallus and a thin thallus type. However, both morphotypes cultured under the same condition in the laboratory could transform into the same thin-thallus type observed in the field. `Green tide' caused by `U. lactuca' occur almost regularly in Station 1 of Mactan Island, reaching an average biomass of up to 2.6 kg wet wt m−2 (or 0.5 kg dry wt m−2). Ulva reticulata, although was less abundant in the rocky tidal zone at most times, reaching an average biomass of only up to 0.15 kg wet wt m−2 (or 0.03 kg dry wt m−2) had caused green tide in Station 2 around February–March. Reproductive structures were not observed in both Ulva species during the survey period suggesting that vegetative fragmentation is the main mode of propagation. Vegetative tissues excised from the thallus can be induced to release biflagellated large and small zooids.
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different life histories of enteromorpha prolifera Ulvales chlorophyta from four rivers on shikoku island japan
Phycologia, 2003Co-Authors: Masanori Hiraoka, Satoshi Shimada, Akinori Dan, Masaru Hagihira, Masao Migita, Masao OhnoAbstract:Populations of Enteromorpha prolifera collected from four rivers on Shikoku Island in Japan had three different types of life history. One type was the typical sexual life history of Enteromorpha, ...
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asexual life history by quadriflagellate swarmers of ulva spinulosa Ulvales ulvophyceae
Phycological Research, 2003Co-Authors: Masanori Hiraoka, Satoshi Shimada, Masao Ohno, Yukihiko SerisawaAbstract:SUMMARY This is the first report of a Ulva species reproducing asexually solely by quadriflagellate swarmers. Ulva spinulosa Okamura et Segawa specimens were collected from Ukibuchi on the Pacific coast of Kochi Prefecture, southern Japan. Quadriflagellate swarmers were released from these specimens. The swarmers showed negative phototaxis before settlement. Thalli cultured from these swarmers also released quadriflagellate swarmers in culture. Microspectrophotometric studies demonstrated equivalent DNA in nuclei of vegetative cells in thalli of U. spinulosa and in sporo-phytes of the other Ulva species with sexual life history (U. fasciata Delile). Furthermore, the quadriflagellate swarmers of U. spinulosa had the same DNA value, demonstrating that the quadriflagellate swarmers are produced without meiosis.
