Table 5 - uploaded by David J. Garbary
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Antithamnion cruciatum: number and distribution of mitochondria in apical cells and cells two to six in determinate axes of tetrasporophytic thalli. Numbers indicate mean ± s.d.
Source publication
Mitochondrial distribution and abundance were assessed during the growth of apical and subapical cells in the red algae Colaconema caespitosum (J. Agardh) Jackelman, Stegenga and Bolton and Antithamnion cruciatum (C. Agardh) N?geli after staining with 3,3?-dihexyloxacarbocyanine iodide [DiOC6(3)] and 2,4?-dimethylaminostyryl-Nethylpyridinium iodide...
Contexts in source publication
Context 1
... and subapical cells of determinate branches: As with the indeterminate axes, the mitochondria in api- cal cells of determinate branches increased. Mitochondria were evenly distributed during apical cell growth and there was a doubling of mitochondria during cell elonga- tion from 30 to 60 (Table 5). The mitochondrial comple- ment of small apical cells was half that in the larger cells and half that present in the lower portion of the enlarged apical cell. ...
Context 2
... the subapical cell elongated there was a corresponding increase in mitochondria. Following cytokinesis, mitochondria were initially evenly distrib- uted (Cell 2, Table 5); however, in cells 3-6 there was a conspicuous concentration of mitochondria in the middle third of the cell (ca. 40-50% of total mitochondria) ( Table 5). ...
Citations
... Consistent with the DAPI staining of fixed Colaconema caespitosum (J. Agardh) Jackelman, Stegenga & J.J. Bolton [26], a single nucleus was visualised in each living cell by Hoechst 33342 dye (Fig 2C). The cell next to the injured site started to regrow (S1 Video). ...
Regeneration is a widely observed phenomenon by which the integrity of an organism is recovered after damage. To date, studies on the molecular and cellular mechanisms of regeneration have been limited to a handful of model multicellular organisms. Here, the regeneration ability of marine macroalgae (Rhodophyta, Phaeophyceae, Chlorophyta) was systematically surveyed after thallus severing. Live cell imaging on severed thalli uncovered the cellular response to the damage. Three types of responses–budding, rhizoid formation, and/or sporulation–were observed in 25 species among 66 examined, proving the high potential of regeneration of macroalgae. The cellular and nuclear dynamics were monitored during cell repair or rhizoid formation of four phylogenetically diverged species, and the tip growth of the cells near the damaged site was observed as a common response. Nuclear translocation followed tip growth, enabling overall distribution of multinuclei or central positioning of the mononucleus. In contrast, the control of cell cycle events, such as nuclear division and septation, varied in these species. These observations showed that marine macroalgae utilise a variety of regeneration pathways, with some common features. This study also provides a novel methodology of live cell imaging in macroalgae.
... Second, the size of the contig (28,906 bp) is similar to the lengths of other red algal mitochondrial genomes (Table 4. 1). Third, multicellular red algae are known to have large numbers of mitochondria per cell (Garbary and Pei, 2006) and, therefore, many copies of the mitochondrial genome per cell, causing relative enrichment of the mitochondrial genome in the extracted DNA. Thus it is reasonable that the mitochondrial genome resolved as a single contig after assembly. ...
Ph.D. Dissertation, The University of Alabama, 2015
... Second, the size of the contig (28,906 bp) is similar to the lengths of other red algal mitochondrial genomes (Table 1). Third, multicellular red algae are known to have large numbers of mitochondria per cell (Garbary and Pei, 2006) and, therefore, many copies of the mitochondrial genome per cell, causing relative enrichment of the mitochondrial genome in the extracted DNA. Thus it is reasonable that the mitochondrial genome resolved as a single contig after assembly. ...
Although red algae are economically highly valuable for their gelatinous cell wall compounds as well as being integral parts of marine benthic habitats, very little genome data are currently available. We present mitochondrial genome sequence data from the red alga Grateloupia taiwanensis S.-M. Lin & H.-Y. Liang. Comprising 28,906 nucleotide positions, the mitochondrial genome contig contains 25 protein-coding genes and 24 transfer RNA genes. It is highly similar to other red algal genomes in gene content as well as overall structure. An intron in the cox1 gene was found to be shared by G. taiwanensis and Grateloupia angusta (Okamura) S. Kawaguchi & H. W. Wang. We also used whole-genome alignments to compare G. taiwanensis to different groups of red algae, and these results are consistent with the currently accepted phylogeny of Rhodophyta.
© 2014 Marine Biological Laboratory.
Regeneration is a widely observed phenomenon by which the integrity of an organism is recovered after damage. So far, studies on the molecular and cellular mechanisms of regeneration have been limited to a handful of model multicellular organisms. Here, we systematically surveyed the regeneration ability of marine macroalgae (Rhodophyta, Phaeophyceae, Chlorophyta) after thallus severing and applied live cell microscopy on them to uncover the cellular response to the damage. We observed three types of responses - budding, rhizoid formation and/or sporulation - in 25 species among 66 examined, demonstrating the high potential of regeneration of macroalgae. In contrast, callus formation, which often accompanies plant regeneration, was never observed. We monitored the cellular and nuclear dynamics during cell repair or rhizoid formation of four phylogenetically diverged Rhodophyta and Chlorophyta species (Colaconema sp., Dasya sessilis, Cladophora albida, Codium fragile). We observed tip growth of the cells near the damaged site as a common response, despite the difference in the number of nuclei and cells across species. Nuclear translocation follows tip growth, enabling overall uniform distribution of multinuclei (Dasya sessilis, Cladophora albida, Codium fragile) or central positioning of the mononucleus (Colaconema sp.). In contrast, the control of cell cycle events, such as nuclear division and septation, varied in these species. In Dasya sessilis, the division of multinuclei was synchronised, whereas it was not the case in Cladophora albida. Septation was tightly coupled with nuclear division in Colaconema and Dasya but not in others. These observations show that marine macroalgae utilise a variety of regeneration pathways, with some common features. This study also provides a novel methodology of live cell biology in macroalgae, offering a foundation for the future of this under-studied taxon.
