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Currently, there is a lack of knowledge of how complex metal oxide nanomaterials, like LiCoO2 (LCO) nanosheets, interact with eukaryotic green algae. Previously, LCO was reported to cause a number of physiological impacts to Raphidocelis subcapitata including endpoints related to growth, reproduction, pigment & lipid biosynthesis, and carbon biomass assimilation. Furthermore, LCO was proven to physically enter the cells, thus indicating the possibility for it to directly interact with key subcellular components. However, the mechanisms through which LCO interacts with these key subcellular components is still unknown. This study assesses the interactions of LCO at the biointerface of R. subcapitata using a novel multiplexed algal cytological imaging (MACI) assay and machine learning in order to predict its phytotoxic mechanism of action (MoA). Algal cells were exposed to varying concentrations of LCO, and their phenotypic profiles were compared to that of cells treated with reference chemicals which had already established MoAs. Hierarchical clustering and machine learning analyses indicated photosynthetic electron transport to be the most probable phytotoxic MoA of LCO. Additionally, single-cell chlorophyll fluorescence results demonstrated an increase in irreversibly oxidized photosystem II proteins. Lastly, LCO-treated cells were observed to have less nuclei/cell and less DNA content/nucleus when compared to non-treated cell controls.
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Chemically induced phenotype plasticity in the unicellular zygnematophyte, Penium margaritaceum
Abstract Phenotypic plasticity allows a plant cell to alter its structure and function in response to external pressure. This adaptive phenomenon has also been important in the evolution of plants including the emergence of land plants from a streptophyte alga.Penium margaritaceumis a unicellular zygnematophyte (i.e., the group of streptophyte algae that is sister to land plants) that was employed in order to study phenotypic plasticity with a focus on the role of subcellular expansion centers and the cell wall in this process. Live cell fluorescence labeling, immunofluorescence labeling, transmission electron microscopy, and scanning electron microscopy showed significant subcellular changes and alterations to the cell wall. When treated with the actin-perturbing agent, cytochalasin E, cytokinesis is arrested and cells are transformed into pseudo-filaments made of up to eight or more cellular units. When treated with the cyclin-dependent kinase (CDK) inhibitor, roscovitine, cells converted to a unique phenotype with a narrow isthmus zone.
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- Award ID(s):
- 2129443
- PAR ID:
- 10521164
- Publisher / Repository:
- Springer Science + Business Media
- Date Published:
- Journal Name:
- Protoplasma
- Volume:
- 261
- Issue:
- 6
- ISSN:
- 0033-183X
- Format(s):
- Medium: X Size: p. 1233-1249
- Size(s):
- p. 1233-1249
- Sponsoring Org:
- National Science Foundation
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