JoVE Visualize What is visualize?
Stop Reading. Start Watching.
Advanced Search
Stop Reading. Start Watching.
Regular Search
Find video protocols related to scientific articles indexed in Pubmed.
New "missing link" genus of the colonial volvocine green algae gives insights into the evolution of oogamy.
BMC Evol. Biol.
PUBLISHED: 02-25-2014
Show Abstract
Hide Abstract
The evolution of oogamy from isogamy, an important biological event, can be summarized as follows: morphologically similar gametes (isogametes) differentiated into small "male" and large "female" motile gametes during anisogamy, from which immotile female gametes (eggs) evolved. The volvocine green algae represent a model lineage to study this type of sex evolution and show two types of gametic unions: conjugation between isogametes outside the parental colonies (external fertilization during isogamy) and fertilization between small motile gametes (sperm) and large gametes (eggs) inside the female colony (internal fertilization during anisogamy and oogamy). Although recent cultural studies on volvocine algae revealed morphological diversity and molecular genetic data of sexual reproduction, an intermediate type of union between these two gametic unions has not been identified.
Related JoVE Video
Another origin of coloniality in volvocaleans: the phylogenetic position of Pyrobotrys arnoldi (Spondylomoraceae, Volvocales).
J. Eukaryot. Microbiol.
PUBLISHED: 06-10-2010
Show Abstract
Hide Abstract
Colonial volvocaleans (Chlorophyceae) are used as a standard model of multicellular evolution. However, the phylogenetic position of the colonial volvocalean family Spondylomoraceae has yet to be resolved. To examine this, the molecular phylogenies of Pyrobotrys stellata and Pyrobotrys squarrosa were analyzed using combined 18S rRNA, RUBISCO large subunit, and P700 chl a-apoprotein A2 gene sequences. In the phylogenetic trees, Pyrobotrys belonged to the clade Caudivolvoxa and was not closely related to other colonial volvocalean flagellates. The results indicate that colony formation of Spondylomoraceae independently evolved from unicellular volvocaleans. The phylogenetic position of problematic "Pascherina tetras" SAG 159-1 was also analyzed.
Related JoVE Video
Recharacterization of Chlamydomonas reinhardtii and its relatives with new isolates from Japan.
J. Plant Res.
PUBLISHED: 07-13-2009
Show Abstract
Hide Abstract
Chlamydomonas reinhardtii P. A. Dang. (Volvocales, Chlorophyceae) is one of the most intensely studied algae, and its whole genome was sequenced. Although this species was originally described based on materials from France and is often referred to as a cosmopolitan species, all culture strains available today have been isolated from eastern North America. The distinctions with similar and/or closely related species, such as Chlamydomonas globosa J. Snow and Chlamydomonas orbicularis E. G. Pringsh., are also contentious. In this study, new strains of C. reinhardtii and C. globosa were isolated from Japan and compared with several strains similar to C. reinhardtii. Based on the morphological, genealogical, phylogenetical, and mating studies including the new Japanese strains, the circumscription of C. reinhardtii was clarified. C. reinhardtii was most closely related to C. globosa, and they were shown to be different species. Although C. reinhardtii was similar to C. orbicularis, the authentic strain of C. orbicularis was morphologically distinguishable and phylogenetically distant from C. reinhardtii. Discovery of the Japanese strains of C. reinhardtii supports the cosmopolitan distribution of this species. Based on Japanese strains and/or strains from other countries, emended descriptions of C. reinhardtii, C. globosa, and C. orbicularis are given.
Related JoVE Video
Phylogenetic positions of Glaucophyta, green plants (Archaeplastida) and Haptophyta (Chromalveolata) as deduced from slowly evolving nuclear genes.
Mol. Phylogenet. Evol.
PUBLISHED: 03-11-2009
Show Abstract
Hide Abstract
The phylogenetic positions of the primary photosynthetic eukaryotes, or Archaeplastida (green plants, red algae, and glaucophytes) and the secondary photosynthetic chromalveolates, Haptophyta, vary depending on the data matrices used in the previous nuclear multigene phylogenetic studies. Here, we deduced the phylogeny of three groups of Archaeplastida and Haptophyta on the basis of sequences of the multiple slowly evolving nuclear genes and reduced the gaps or missing data, especially in glaucophyte operational taxonomic units (OTUs). The present multigene phylogenetic analyses resolved that Haptophyta and two other groups of Chromalveolata, stramenopiles and Alveolata, form a monophyletic group that is sister to the green plants and that the glaucophytes and red algae are basal to the clade composed of green plants and Chromalveolata. The bootstrap values supporting these phylogenetic relationships increased with the exclusion of long-branched OTUs. The close relationship between green plants and Chromalveolata is further supported by the common replacement in two plastid-targeted genes.
Related JoVE Video
Metabolic and morphological changes of an oil accumulating trebouxiophycean alga in nitrogen-deficient conditions.
Metabolomics
Show Abstract
Hide Abstract
Oil-rich algae have promising potential for a next-generation biofuel feedstock. Pseudochoricystis ellipsoidea MBIC 11204, a novel unicellular green algal strain, accumulates a large amount of oil (lipids) in nitrogen-deficient (-N) conditions. Although the oil bodies are easily visualized by lipophilic staining in the cells, little is known about how oil bodies are metabolically synthesized. Clarifying the metabolic profiles in -N conditions is important to understand the physiological mechanisms of lipid accumulations and will be useful to optimize culture conditions efficiently produce industrial oil. Metabolome and lipidome profiles were obtained, respectively, using capillary electrophoresis- and liquid chromatography-mass spectrometry from P. ellipsoidea in both nitrogen-rich (+N; rapid growth) and -N conditions. Relative quantities of more than 300 metabolites were systematically compared between these two conditions. Amino acids in nitrogen assimilation and N-transporting metabolisms were decreased to 1/20 the amount, or less, in -N conditions. In lipid metabolism, the quantities of neutral lipids increased greatly in -N conditions; however, quantities of nearly all the other lipids either decreased or only changed slightly. The morphological changes in +N and -N conditions were also provided by microscopy, and we discuss their relationship to the metabolic changes. This is the first approach to understand the novel algal strains metabolism using a combination of wide-scale metabolome analysis and morphological analysis.
Related JoVE Video

What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

How does it work?

We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.