... H. Ettl, Taxonomische Namensänderungen und Neubeschreibungen unter den Phytomonadina (Chlorop... more ... H. Ettl, Taxonomische Namensänderungen und Neubeschreibungen unter den Phytomonadina (Chlorophyta), Nova Hedwigia 35 (1983), pp. ... 9294. B. Marin and M. Melkonian, Mesostigmatophyceae, a new class of streptophyte green algae revealed by SSU rRNA sequence ...
... INTRODUCTION The green algal class Prasinophyceae as presently conceived consists of 14 flage... more ... INTRODUCTION The green algal class Prasinophyceae as presently conceived consists of 14 flagellate and I or 2 non-flagellate genera (Moe strup & Throndsen 1988; Eikrem & Throndsen 1990; Melko nian 1990; Guillard et at. 1991; Inouye & Hori 1991). ...
<b>Copyright information:</b>Taken from "The ancestor of the chromatophore obtai... more <b>Copyright information:</b>Taken from "The ancestor of the chromatophore obtained a carboxysomal operon by horizontal gene transfer from a -like γ-proteobacterium"http://www.biomedcentral.com/1471-2148/7/85BMC Evolutionary Biology 2007;7():85-85.Published online 5 Jun 2007PMCID:PMC1904183.gure 1 (4317 vs. 4126 characters). . Phylogeny inferred from concatenated and rDNA sequences. Tree topologies resulted from ML analyses using a GTR+I+Γ model; significance values shown as in Figure 1.
Genome analysis of the pico-eukaryotic marine green alga Prasinoderma coloniale CCMP 1413 unveils... more Genome analysis of the pico-eukaryotic marine green alga Prasinoderma coloniale CCMP 1413 unveils the existence of a novel phylum within green plants (Viridiplantae), the Prasinodermophyta, which diverged before the split of Chlorophyta and Streptophyta. Structural features of the genome and gene family comparisons revealed an intermediate position of the P. coloniale genome (25.3 Mb) between the extremely compact, small genomes of picoplanktonic Mamiellophyceae (Chlorophyta) and the larger, more complex genomes of early-diverging streptophyte algae. Reconstruction of the minimal core genome of Viridiplantae allowed identification of an ancestral toolkit of transcription factors and flagellar proteins. Adaptations of P. coloniale to its deep-water, oligotrophic environment involved expansion of light-harvesting proteins, reduction of early light-induced proteins, evolution of a distinct type of C4 photosynthesis and carbon-concentrating mechanism, synthesis of the metal-complexing m...
The class Pedinophyceae was established for asymmetric uniflagellate green algae, and was origina... more The class Pedinophyceae was established for asymmetric uniflagellate green algae, and was originally considered as an ancestral lineage of viridiplants. However, analyses of 71 concatenated plastid proteins [Turmel et al. (2009): Mol. Biol. Evol. 26: 2317-2331] recovered Pedinomonas within the Chlorellales (Trebouxiophyceae), thereby questioning the Pedinophyceae as an independent class. For the present study, complete nuclear and plastid-encoded rRNA operon sequences have been determined for 37 taxa of green algae including 6 members of the Pedinophyceae, providing 9272 aligned nucleotide positions. Phylogenies using both rRNA operons consistently rejected any relationship between Pedinophyceae and the Chlorellales. Instead, the Pedinophyceae were significantly resolved as sister of all phycoplast-containing 'core' chlorophytes, i.e. Chlorodendrophyceae, Trebouxiophyceae, Ulvophyceae and Chlorophyceae. Reinvestigation of plastid proteins discovered biased phylogenetic signa...
Land plants (embryophytes) evolved from streptophyte green algae, a small group of freshwater alg... more Land plants (embryophytes) evolved from streptophyte green algae, a small group of freshwater algae ranging from scaly, unicellular flagellates (Mesostigma) to complex, filamentous thalli with branching, cell differentiation and apical growth (Charales). Streptophyte algae and embryophytes form the division Streptophyta, whereas the remaining green algae are classified as Chlorophyta. The Charales (stoneworts) are often considered to be sister to land plants, suggesting progressive evolution towards cellular complexity within streptophyte green algae. Many cellular (e.g. phragmoplast, plasmodesmata, hexameric cellulose synthase, structure of flagellated cells, oogamous sexual reproduction with zygote retention) and physiological characters (e.g. type of photorespiration, phytochrome system) originated within streptophyte algae. Phylogenetic studies have demonstrated that Mesostigma (flagellate) and Chlorokybus (sarcinoid) form the earliest divergence within streptophytes, as sister ...
One of the major steps in the evolution of life was the origin of photosynthesis in nucleated cel... more One of the major steps in the evolution of life was the origin of photosynthesis in nucleated cells underpinning the evolution of plants. It is well accepted that this evolutionary process was initiated when a photosynthetic bacterium (a cyanobacterium) was taken up by a colorless host cell, probably more than a billion years ago, and transformed into a photosynthetic organelle (a plastid) during a process known as primary endosymbiosis. Here, we use sequence comparisons and phylogenetic analyses of the prokaryotic rDNA operon to show that the thecate, filose amoeba Paulinella chromatophora Lauterborn obtained its photosynthetic organelles by a similar but more recent process, which involved a different cyanobacterium, indicating that the evolution of photosynthetic organelles from cyanobacteria was not a unique event, as is commonly believed, but may be an ongoing process.
WD40/BEACH domain proteins have been implicated in membrane trafficking and membrane composition ... more WD40/BEACH domain proteins have been implicated in membrane trafficking and membrane composition events in Dictyostelium and Drosophila. In this paper, we show that the Arabidopsis SPIRRIG (SPI) gene encodes a WD40/BEACH domain protein. The cellular analysis revealed fragmented vacuoles in root hairs similar to those found in the corresponding Dictyostelium mutants, suggesting a related cellular function. The phenotypic analysis revealed that spi mutants share all phenotypic aspects of mutants in the actin polymerization-regulating ARP2/3 pathway, including distorted trichomes, less lobing of epidermal pavement cells, disconnected epidermal cells on various organs, and shorter root hairs. This complete phenotypic overlap suggests that this WD40/BEACH domain protein and the actin-regulating ARP2/3 pathway are involved in similar growth processes.
... H. Ettl, Taxonomische Namensänderungen und Neubeschreibungen unter den Phytomonadina (Chlorop... more ... H. Ettl, Taxonomische Namensänderungen und Neubeschreibungen unter den Phytomonadina (Chlorophyta), Nova Hedwigia 35 (1983), pp. ... 9294. B. Marin and M. Melkonian, Mesostigmatophyceae, a new class of streptophyte green algae revealed by SSU rRNA sequence ...
... INTRODUCTION The green algal class Prasinophyceae as presently conceived consists of 14 flage... more ... INTRODUCTION The green algal class Prasinophyceae as presently conceived consists of 14 flagellate and I or 2 non-flagellate genera (Moe strup & Throndsen 1988; Eikrem & Throndsen 1990; Melko nian 1990; Guillard et at. 1991; Inouye & Hori 1991). ...
<b>Copyright information:</b>Taken from "The ancestor of the chromatophore obtai... more <b>Copyright information:</b>Taken from "The ancestor of the chromatophore obtained a carboxysomal operon by horizontal gene transfer from a -like γ-proteobacterium"http://www.biomedcentral.com/1471-2148/7/85BMC Evolutionary Biology 2007;7():85-85.Published online 5 Jun 2007PMCID:PMC1904183.gure 1 (4317 vs. 4126 characters). . Phylogeny inferred from concatenated and rDNA sequences. Tree topologies resulted from ML analyses using a GTR+I+Γ model; significance values shown as in Figure 1.
Genome analysis of the pico-eukaryotic marine green alga Prasinoderma coloniale CCMP 1413 unveils... more Genome analysis of the pico-eukaryotic marine green alga Prasinoderma coloniale CCMP 1413 unveils the existence of a novel phylum within green plants (Viridiplantae), the Prasinodermophyta, which diverged before the split of Chlorophyta and Streptophyta. Structural features of the genome and gene family comparisons revealed an intermediate position of the P. coloniale genome (25.3 Mb) between the extremely compact, small genomes of picoplanktonic Mamiellophyceae (Chlorophyta) and the larger, more complex genomes of early-diverging streptophyte algae. Reconstruction of the minimal core genome of Viridiplantae allowed identification of an ancestral toolkit of transcription factors and flagellar proteins. Adaptations of P. coloniale to its deep-water, oligotrophic environment involved expansion of light-harvesting proteins, reduction of early light-induced proteins, evolution of a distinct type of C4 photosynthesis and carbon-concentrating mechanism, synthesis of the metal-complexing m...
The class Pedinophyceae was established for asymmetric uniflagellate green algae, and was origina... more The class Pedinophyceae was established for asymmetric uniflagellate green algae, and was originally considered as an ancestral lineage of viridiplants. However, analyses of 71 concatenated plastid proteins [Turmel et al. (2009): Mol. Biol. Evol. 26: 2317-2331] recovered Pedinomonas within the Chlorellales (Trebouxiophyceae), thereby questioning the Pedinophyceae as an independent class. For the present study, complete nuclear and plastid-encoded rRNA operon sequences have been determined for 37 taxa of green algae including 6 members of the Pedinophyceae, providing 9272 aligned nucleotide positions. Phylogenies using both rRNA operons consistently rejected any relationship between Pedinophyceae and the Chlorellales. Instead, the Pedinophyceae were significantly resolved as sister of all phycoplast-containing 'core' chlorophytes, i.e. Chlorodendrophyceae, Trebouxiophyceae, Ulvophyceae and Chlorophyceae. Reinvestigation of plastid proteins discovered biased phylogenetic signa...
Land plants (embryophytes) evolved from streptophyte green algae, a small group of freshwater alg... more Land plants (embryophytes) evolved from streptophyte green algae, a small group of freshwater algae ranging from scaly, unicellular flagellates (Mesostigma) to complex, filamentous thalli with branching, cell differentiation and apical growth (Charales). Streptophyte algae and embryophytes form the division Streptophyta, whereas the remaining green algae are classified as Chlorophyta. The Charales (stoneworts) are often considered to be sister to land plants, suggesting progressive evolution towards cellular complexity within streptophyte green algae. Many cellular (e.g. phragmoplast, plasmodesmata, hexameric cellulose synthase, structure of flagellated cells, oogamous sexual reproduction with zygote retention) and physiological characters (e.g. type of photorespiration, phytochrome system) originated within streptophyte algae. Phylogenetic studies have demonstrated that Mesostigma (flagellate) and Chlorokybus (sarcinoid) form the earliest divergence within streptophytes, as sister ...
One of the major steps in the evolution of life was the origin of photosynthesis in nucleated cel... more One of the major steps in the evolution of life was the origin of photosynthesis in nucleated cells underpinning the evolution of plants. It is well accepted that this evolutionary process was initiated when a photosynthetic bacterium (a cyanobacterium) was taken up by a colorless host cell, probably more than a billion years ago, and transformed into a photosynthetic organelle (a plastid) during a process known as primary endosymbiosis. Here, we use sequence comparisons and phylogenetic analyses of the prokaryotic rDNA operon to show that the thecate, filose amoeba Paulinella chromatophora Lauterborn obtained its photosynthetic organelles by a similar but more recent process, which involved a different cyanobacterium, indicating that the evolution of photosynthetic organelles from cyanobacteria was not a unique event, as is commonly believed, but may be an ongoing process.
WD40/BEACH domain proteins have been implicated in membrane trafficking and membrane composition ... more WD40/BEACH domain proteins have been implicated in membrane trafficking and membrane composition events in Dictyostelium and Drosophila. In this paper, we show that the Arabidopsis SPIRRIG (SPI) gene encodes a WD40/BEACH domain protein. The cellular analysis revealed fragmented vacuoles in root hairs similar to those found in the corresponding Dictyostelium mutants, suggesting a related cellular function. The phenotypic analysis revealed that spi mutants share all phenotypic aspects of mutants in the actin polymerization-regulating ARP2/3 pathway, including distorted trichomes, less lobing of epidermal pavement cells, disconnected epidermal cells on various organs, and shorter root hairs. This complete phenotypic overlap suggests that this WD40/BEACH domain protein and the actin-regulating ARP2/3 pathway are involved in similar growth processes.
Uploads
Papers by Birger Marin