Ultrastructural changes in rust-infected tissues of flax and sunflower

1972 ◽  
Vol 50 (7) ◽  
pp. 1485-1492 ◽  
Author(s):  
Michael D. Coffey ◽  
Barry A. Palevitz ◽  
Paul J. Allen
Keyword(s):  
Single Cell ◽  
Host Cell ◽  
Plant Species ◽  
Cell Structure ◽  
Host Tissue ◽  
Ultrastructural Changes ◽  
Cell Organelles ◽  
Starch Grains ◽  
Major Alteration ◽  
Marked Tendency

Similar changes occurred in the ultrastructure of host cell organelles in the rust-infected tissues of both flax and sunflower. Up to the onset of sporulation at 8 days after inoculation the only major alteration in cell structure was a marked tendency for the cell organelles to be aggregated around the intracellular fungal haustorium and an accumulation of starch in the plastids. During sporulation, however, some striking changes occurred in the structure of plastids, mitochondria, and microbodies. Eleven days after inoculation, in a zone of host tissue adjacent to the rust pustule, the plastids no longer contained starch and varied in structure even within a single cell. Some were similar to normal chloroplasts, others had larger grana, and some bore a close resemblance to chromoplasts. In sunflower, but not in flax, mitochondria contained atypical plate-like cristae in addition to the usual vesiculate type. The micro-bodies of both plant species all contained crystalline cores in contrast to earlier stages in the disease where crystals were only occasionally detected. The plastids were also altered considerably in another zone of tissue situated beneath the rust pustule. In some plastids the thylakoids extended along their long axis, forming several large grana, and in others the large grana were interconnected by lamellae arranged in a vesicular or tubular configuration. Frequently the starch grains in these plastids were broken down into small rosettes of darkly staining particles with an appearance similar to that of animal glycogen.

Ultrastructural Changes in the Root Meristem Cells of Rubus Chamaemorus L. (Cloudberry)

1975 ◽  
Vol 33 ◽  
pp. 562-563
Author(s):  
Arya K. Bal
Keyword(s):  
Root Meristem ◽  
Uranyl Acetate ◽  
Particulate Material ◽  
Ultrastructural Changes ◽  
Cell Organelles ◽  
Cytoplasmic Matrix ◽  
Golgi Membranes ◽  
Rubus Chamaemorus ◽  
Dense Substance ◽  
Ultrathin Sections

In the course of studies in the root meristem tissue of Rubus chamaemorus L. some important changes in the ultrastructural morphology were observed during the initiation of senescence at the end of the growing season.Root meristems were collected from naturally growing healthy populations of Cloudberry plants, and fixed in Karnovsky's mixture or in 2.5% glutaraldehyde in phosphate buffer. The samples were osmicated, dehydrated following usual methods and embedded in Epon. Ultrathin sections were stained in uranyl acetate and lead citrate.Figure 1 shows part of a dense cell in the meristem. The electron density of these cells is due to large amounts of a particulate material in the cytoplasmic matrix. The smallest particle seen in electron micrographs is about 40 A, although larger aggregates are also found, which remain randomly distributed in association with various cell organelles. Dense substance has been found associated with golgi membranes, proplastids, vacuoles and microtubules (Fig. 2).

Influence de la température et de la durée d'un traitement cryoprotecteur sur la résistance au froid de plantules de blé. Étude ultrastructurale des ébauches foliaires

1983 ◽  
Vol 61 (4) ◽  
pp. 1025-1039 ◽  
Author(s):  
C. M. Gazeau
Keyword(s):  
Endoplasmic Reticulum ◽  
Treatment Period ◽  
Day Treatment ◽  
Leaf Primordia ◽  
Ultrastructural Changes ◽  
Distilled Water ◽  
Wheat Seedlings ◽  
Starch Grains ◽  
Different Temperatures ◽  
Protective Treatment

Wheat seedlings were treated at different temperatures and for various periods of time with a cold-protective substance, composed of a mixture of glycerol, dimethylsulfoxide, and saccharose. When the treatment was done at 20 °C, slight ultrastructural changes appeared in leaf primordia as soon as day 1. Thus numbers of lipid globules increased significantly. When the treatment period was increased to 4 days, numbers of starch grains increased, and there was a marked enlargement of mitochondria and plasts. When the treatment was done at 2 °C, cytoplasmic alterations occurred later than at 20 °C. After a 4-day treatment, they were similar to changes induced at 20 °C. When the treatment period was increased to 12 days, dictyosomes were markedly altered. They clustered close to the nucleus in two or three groups and gave rise to numerous pale vesicles with various shapes and sizes. Around each cluster of such vesicles, there gathered many endoplasmic reticulum vesicles and other organelles (mitochondria, plasts, microbodies, vacuoles). A further cooling of 1 °C/min, down to −15 or −30 °C, enhanced these phenomena. After the seedlings were warmed up to 20 °C in distilled water, the changes induced by the frost-protective treatment and then by freezing were shown to be reversible. [Journal translation]

The ultrastructure of M1-a-mediated resistance to powdery mildew infection in barley

1975 ◽  
Vol 53 (22) ◽  
pp. 2589-2597 ◽  
Author(s):  
H. H. Edwards
Keyword(s):  
Powdery Mildew ◽  
Host Cell ◽  
Electron Density ◽  
Epidermal Cells ◽  
Dense Material ◽  
Ultrastructural Changes ◽  
Electron Dense Material ◽  
Host Cytoplasm ◽  
Powdery Mildew Infection ◽  
Cell Protoplast

M1-a-mediated resistance in barley to invasion by the CR3 race of Erysiphe graminis f. sp. hordei does not occur in every host cell with the same speed and severity. In some cells ultrastructural changes within the host cell as a result of resistance will occur within 24 h after inoculation, whereas in other cells these changes may take up to 72 h. In some cells the ultrastructural changes are so drastic that they give the appearance of a hypersensitive death of the host cell, whereas in other cells the changes are very slight. In any case, at the end of these changes the fungus ceases growth. The ultrastructural changes occur in penetrated host epidermal cells as well as non-infected adjacent epidermal and mesophyll cells.The following ultrastructural changes have been observed: (1) an electron-dense material which occurs either free in the vacuole or adhering to the tonoplast (the material is granular or in large clumps); (2) an increased electron density of the host cytoplasm and nucleus; (3) a breakdown of the tonoplast so that the cytoplasmic constituents become dispersed throughout the cell lumen; and (4) the deposition of papillar-like material in areas other than the penetration site. The first three changes take place within the host cell protoplasts and are directly attributable to the gene M1-a. These changes are typical of stress or incompatibility responses and thus M1-a appears to trigger a generalized incompatibility response in the presence of race CR3. The papillar-like material occurs outside the host cell protoplast in the same manner as the papilla and probably is not directly attributable to M1-a.

scholarly journals Cold stress effects on organelle ultrastructure in polar Caryophyllaceae species

2014 ◽  
Vol 35 (4) ◽  
pp. 627-646 ◽  
Author(s):  
Irena Giełwanowska ◽  
Marta Pastorczyk ◽  
Maja Lisowska ◽  
Michał Węgrzyn ◽  
Ryszard J. Górecki
Keyword(s):  
Cold Stress ◽  
Conformational Dynamics ◽  
South Shetland Islands ◽  
Ultrastructural Changes ◽  
Adjacent Cell ◽  
Crystalline Inclusion ◽  
Polar Regions ◽  
Cell Nuclei ◽  
Cell Organelles ◽  
Svalbard Archipelago

AbstractThis study investigated leaf mesophyll cells of Caryophyllaceae plants growing in polar regions – Cerastium alpinum and Silene involucrata from the Hornsund region of Spitsbergen island (Svalbard Archipelago, Arctic), and Colobanthus quitensis from the Admiralty Bay region on King George Island (South Shetland Islands, West Antarctic). Ultrastructural changes were analyzed in mesophyll protoplasts of plants growing in natural Arctic and Antarctic habitats and plants grown in a greenhouse, including plants exposed to short-term cold stress under semi-controlled conditions. Cell organelles of plants growing in natural polar habitats and greenhouse-grown plants were characterized by significant morphological plasticity. Chloroplasts of plants studied in this work formed variously shaped protrusions and invaginations that visibly increased the contact area between adjacent cell compartments and reduced the distance between organelles. S. involucrata plants grown under greenhouse conditions, tested by us in this work, were characterized by highly dynamic cell nuclei with single or multiple invaginations of the nuclear membrane and the presence of channels and cisternae filled with cytoplasm and organelles. Crystalline inclusion proteins were observed in the cell nuclei of C. quitensis between nuclear membranes and in the direct proximity of heterochromatin. Our study revealed significant conformational dynamics of organelles, manifested by variations in the optical density of matrices, membranes and envelopes, in particular in C. quitensis, which could suggest that the analyzed Caryophyllaceae taxa are well adapted to severe climate and changing conditions in polar regions.

scholarly journals The Influence of Symbiont Diversity on the Functional Biology of a Model Sea Anemone

2021 ◽  
Author(s):  
◽  
Dorota Ewa Starzak
Keyword(s):  
Coral Reefs ◽  
Host Cell ◽  
Metabolic Cost ◽  
Global Scale ◽  
Sea Anemone ◽  
Host Tissue ◽  
Sea Anemones ◽  
Dominant Type ◽  
Symbiodinium Type ◽  
Symbiont Type

<p>Cnidarian–dinoflagellate symbioses, particularly those between anthozoans and dinoflagellates of the genus Symbiodinium (commonly referred to as zooxanthellae) are widespread in the marine environment. They are responsible for the formation of coral reefs and are thus of great ecological importance. In recent years there has been an increase in the frequency and severity of episodes of coral bleaching resulting in degradation and mortality of coral reefs on a global scale. In order to gain a deeper understanding of how corals can adapt to changing environmental conditions, the effect that symbiont type has on the persistence and physiology of an association needs to be ascertained. The aim of this research was to determine how different symbiont types affect the nutritional biology and intracellular physiology of the symbiosis when in association with the sea anemone Aiptasia pulchella. The specific objectives of the study were to; (1) determine whether different symbiont types are equally as adept at supporting the energetic demands of the same host; (2) determine if internal pH (pHi) is a reflection of symbiont type and whether the optimal pH for photosynthesis coincides with the host cell pHi; and (3) test the influence of Symbiodinium type on host tissue glycerol and glucose pools. In order to answer these questions, aposymbiotic (i.e. symbiont-free) sea anemones were infected with different Symbiodinium types and the relationship between symbiont type, photosynthetic performance and autotrophic potential was tested. A range of ‘normal’ and novel cnidarian–dinoflagellate symbioses was also used to measure host cell pHi and to determine the optimal pHi of isolated intact symbiosomes (i.e. the vacuoles that house the symbionts), as well as to compare the amounts of free glycerol and glucose (metabolites) present in the host tissues. Different host-symbiont combinations were found to have different photosynthetic and respiratory attributes. Earlier onset of full autotrophy (i.e. when all metabolic carbon demands of the symbiosis were met by photosynthesis) and higher CZAR values (i.e. the contribution of zooxanthellae to animal respiration) were demonstrated by symbioses hosting Symbiodinium B1 both from the original (homologous) and different (heterologous) host. The study showed that Symbiodinium types differ in their pH optima and that the optimal pHi for photosynthesis does not always match the actual measured pHi. Symbiont type was also shown to have an effect on host tissue glycerol and glucose pools, with the associations harbouring the homologous Symbiodinium B1 attaining the highest concentrations of both metabolites. Findings from this study suggest that corals may be able to maintain an association with a range of Symbiodinium types, and hence potentially switch as a consequence of bleaching. The new symbiont type may not be as nutritionally advantageous as the original type however, which could have implications for the growth and survivorship of the coral, unless it is able to supplement its carbon demands heterotrophically. The rapid proliferation of some of the heterologous Symbiodinium types (e.g. Symbiodinium E2) inside the host indicates that, after bleaching, there is potential for fast symbiont establishment. The reduced carbon contribution of these heterologous symbionts may not be a major concern should the coral be able to reinstate the more nutritionally advantageous symbiont as the dominant type during bleaching recovery. Finally, the rapid proliferation demonstrated by the heterologous Symbiodinium types and the associated metabolic cost to the host, could be an indication of the opportunistic nature of some of these types and may indicate a shift towards parasitism. It is imperative to extend this type of work to corals in the field to determine how these associations behave in nature. Also, in order to get a clearer picture of the diversity in symbiosis physiology, a wider range of Symbiodinium types needs to be investigated.</p>

scholarly journals Single-Cell Analysis of the Impact of Host Cell Heterogeneity on Infection with Foot-and-Mouth Disease Virus

2018 ◽  
Vol 92 (9) ◽  
pp. e00179-18 ◽  
Author(s):  
Xiu Xin ◽  
Hailong Wang ◽  
Lingling Han ◽  
Mingzhen Wang ◽  
Hui Fang ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Single Cell ◽  
Host Cell ◽  
Cell Size ◽  
Single Cell Analysis ◽  
Foot And Mouth Disease ◽  
Cell Analysis ◽  
Cell Heterogeneity ◽  
Mouth Disease Virus ◽  
Foot And Mouth

ABSTRACTViral infection and replication are affected by host cell heterogeneity, but the mechanisms underlying the effects remain unclear. Using single-cell analysis, we investigated the effects of host cell heterogeneity, including cell size, inclusion, and cell cycle, on foot-and-mouth disease virus (FMDV) infection (acute and persistent infections) and replication. We detected various viral genome replication levels in FMDV-infected cells. Large cells and cells with a high number of inclusions generated more viral RNA copies and viral protein and a higher proportion of infectious cells than other cells. Additionally, we found that the viral titer was 10- to 100-fold higher in cells in G2/M than those in other cell cycle phases and identified a strong correlation between cell size, inclusion, and cell cycle heterogeneity, which all affected the infection and replication of FMDV. Furthermore, we demonstrated that host cell heterogeneity influenced the adsorption of FMDV due to differences in the levels of FMDV integrin receptors expression. Collectively, these results further our understanding of the evolution of a virus in a single host cell.IMPORTANCEIt is important to understand how host cell heterogeneity affects viral infection and replication. Using single-cell analysis, we found that viral genome replication levels exhibited dramatic variability in foot-and-mouth disease virus (FMDV)-infected cells. We also found a strong correlation between heterogeneity in cell size, inclusion number, and cell cycle status and that all of these characteristics affect the infection and replication of FMDV. Moreover, we found that host cell heterogeneity influenced the viral adsorption as differences in the levels of FMDV integrin receptors' expression. This study provided new ideas for the studies of correlation between FMDV infection mechanisms and host cells.

scholarly journals AFM and FluidFM Technologies: Recent Applications in Molecular and Cellular Biology

Scanning ◽  
2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Mohamed Yassine Amarouch ◽  
Jaouad El Hilaly ◽  
Driss Mazouzi
Keyword(s):  
Single Cell ◽  
Protein Interactions ◽  
Single Cells ◽  
Cardiac Cells ◽  
Cellular Biology ◽  
Adhesion Forces ◽  
Cell Organelles ◽  
Force Microscopy ◽  
Imaging Tool ◽  
Atomic Force

Atomic force microscopy (AFM) is a widely used imaging technique in material sciences. After becoming a standard surface-imaging tool, AFM has been proven to be useful in addressing several biological issues such as the characterization of cell organelles, quantification of DNA-protein interactions, cell adhesion forces, and electromechanical properties of living cells. AFM technique has undergone many successful improvements since its invention, including fluidic force microscopy (FluidFM), which combines conventional AFM with microchanneled cantilevers for local liquid dispensing. This technology permitted to overcome challenges linked to single-cell analyses. Indeed, FluidFM allows isolation and injection of single cells, force-controlled patch clamping of beating cardiac cells, serial weighting of micro-objects, and single-cell extraction for molecular analyses. This work aims to review the recent studies of AFM implementation in molecular and cellular biology.

scholarly journals Computational Proteome-Wide Study for the Prediction of Escherichia coli Protein Targeting in Host Cell Organelles and Their Implication in Development of Colon Cancer

ACS Omega ◽  
2020 ◽  
Vol 5 (13) ◽  
pp. 7254-7261 ◽  
Author(s):  
Shahanavaj Khan ◽  
Sabika Zaidi ◽  
Abdulaziz Saleh Alouffi ◽  
Iftekhar Hassan ◽  
Ahmad Imran ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Colon Cancer ◽  
Host Cell ◽  
Protein Targeting ◽  
Cell Organelles

scholarly journals A Newly Designed Modular ZnBr2 Single Cell Structure

Batteries ◽  
2020 ◽  
Vol 6 (2) ◽  
pp. 27
Author(s):  
Zongqiang Pang ◽  
Yutao Gong ◽  
Ming Yuan ◽  
Xin Li
Keyword(s):  
Energy Density ◽  
Single Cell ◽  
Modular Design ◽  
High Reliability ◽  
Low Cost ◽  
Cell Structure ◽  
Performance Testing ◽  
High Energy ◽  
High Energy Density ◽  
Symmetrical Structure

We describe a ZnBr2 single cell which has a highly modular symmetrical structure. With designed polyethylene shell frames, membrane frame and composite titanium-carbon felt electrodes, it has a higher energy density and is more flexible compared with traditional flow batteries. We repeatedly tested its performance, which showed good tightness, high reliability and a high energy efficiency of 75%. Due to the special symmetrical structure and modular design, it is easy to assemble and disassemble, which makes it suitable as a test platform for electrodes, membranes and electrolyte performance testing. The designed modular flow cell has low cost and high energy density, and can provide good guidance for flow battery research.

Eimeria canadensis (Protozoa, Sporozoea): ultrastructure of the host–parasite interface during development of first-generation schizonts in vitro

1980 ◽  
Vol 58 (11) ◽  
pp. 2018-2025 ◽  
Author(s):  
Bodo E. G. Mueller
Keyword(s):  
Host Cell ◽  
Parasitophorous Vacuole ◽  
Eimeria Species ◽  
Outer Zone ◽  
Ultrastructural Observation ◽  
Cell Cytoplasm ◽  
Cell Organelles ◽  
Host Cell Cytoplasm ◽  
Host Parasite

Eimeria canadensis sporozoites were inoculated into monolayer cultures of Madin–Darby bovine kidney and primary bovine embryonic kidney cells. Sporozoites retained their shape for at least 9 days. At that time, the nucleus was enlarged and contained a prominent nucleolus, and amylopectin granules were no longer apparent. The width of the parasitophorous vacuole (pv) between host cell cytoplasm and parasite pellicle widened during transformation of sporozoites into multinucleate schizonts. Areas of altered host cell cytoplasm immediately adjacent to the pv membrane increased in size and became confluent, resulting in the formation of two distinct layers of cytoplasm. The outer zone contained the host cell nucleus, mitochondria, Golgi stacks, and ER, whereas the inner layer appeared granular and was void of all cell organelles except structures resembling ribosomes. Microfilaments were abundant at the border between inner and outer zone. In the most advanced stages observed, host cell organelles persisted only in the perinuclear region. The remaining, attenuated cytoplasm resembled the former inner zone.The novel ultrastructural observation of a bilayered cytoplasm of cells harbouring E. canadensis schizonts is compared with light microscope reports of similar effects caused by other Eimeria species of ruminants and with electron microscope findings of altered intestinal and abomasal cells of sheep harbouring "globidial" schizonts.

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