Induced susceptibility and enhanced resistance at the cellular level in barley coleoptiles. II. Timing and localization of induced susceptibility in a single coleoptile cell and its transfer to an adjacent cell

1986 ◽  
Vol 64 (4) ◽  
pp. 889-895 ◽  
Author(s):  
H. Kunoh ◽  
K. Kuroda ◽  
A. Hayashimoto ◽  
H. Ishizaki
Keyword(s):  
Light Microscopy ◽  
Cellular Level ◽  
Host Cells ◽  
Adjacent Cell ◽  
Erysiphe Pisi ◽  
Time Intervals ◽  
Induced Susceptibility ◽  
Enhanced Resistance ◽  
Entire Cell ◽  
Cytoplasmic Aggregate

The primary growth of both Erysiphe graminis de Candolle and E. pisi de Candolle on the same cell or adjacent cells of barley coleoptiles was observed by light microscopy to determine factors conditioning host cells toward susceptibility. Erysiphe pisi never successfully penetrated (0% efficiency) when it was the sole inoculum. By contrast it penetrated with varied efficiencies when initiation of cytoplasmic aggregates induced by it followed that of E. graminis by 4.0–19.0 h on the same coleoptile cells. When E. graminis induced a cytoplasmic aggregate 4.0–9.0 h earlier than E. pisi in a single coleoptile cell, induced susceptibility was minimal around the E. graminis penetration site, within 100 μm of the site, in the cell. When the time intervals were 9.25 – 14.0 h, induced susceptibility was maximal around the E. graminis penetration site, within 100 μm, and minimal when the fungi were more than 200 μm apart. When the time intervals were more than 14.0 h, induced susceptibility was evenly dispersed throughout the entire cell and transfer of susceptibility to laterally adjacent cells occurred only under these time conditions. Erysiphe pisi penetrations on coleoptile cells were influenced by its growth or the host cell's response before actual penetration occurred.

scholarly journals BAX INHIBITOR-1 Is Required for Full Susceptibility of Barley to Powdery Mildew

2010 ◽  
Vol 23 (9) ◽  
pp. 1217-1227 ◽  
Author(s):  
Ruth Eichmann ◽  
Melanie Bischof ◽  
Corina Weis ◽  
Jane Shaw ◽  
Christophe Lacomme ◽  
...  
Keyword(s):  
Cell Death ◽  
Powdery Mildew ◽  
Gene Silencing ◽  
Defense Responses ◽  
Negative Control ◽  
Cellular Level ◽  
Virus Induced Gene Silencing ◽  
Powdery Mildew Fungus ◽  
Basal Resistance ◽  
Enhanced Resistance

BAX INHIBITOR-1 (BI-1) is one of the few proteins known to have cross-kingdom conserved functions in negative control of programmed cell death. Additionally, barley BI-1 (HvBI-1) suppresses defense responses and basal resistance to the powdery mildew fungus Blumeria graminis f. sp. hordei and enhances resistance to cell death–provoking fungi when overexpressed in barley. Downregulation of HvBI-1 by transient-induced gene silencing or virus-induced gene silencing limited susceptibility to B. graminis f. sp. hordei, suggesting that HvBI-1 is a susceptibility factor toward powdery mildew. Transient silencing of BI-1 did not limit supersusceptibility induced by overexpression of MLO. Transgenic barley plants harboring an HvBI-1 RNA interference (RNAi) construct displayed lower levels of HvBI-1 transcripts and were less susceptible to powdery mildew than wild-type plants. At the cellular level, HvBI-1 RNAi plants had enhanced resistance to penetration by B. graminis f. sp. hordei. These data support a function of BI-1 in modulating cell-wall-associated defense and in establishing full compatibility of B. graminis f. sp. hordei with barley.

PENGARUH KOMBINASI EKSTRAK JERUK BRASTAGI DAN WORTEL PER ORAL SEBELUM AKTIVITAS FISIK TERHADAP PENURUNAN KADAR MDA PLASMA MENCIT SETELAH AKTIVITAS FISIK

2017 ◽  
Vol 1 (1) ◽  
pp. 41
Author(s):  
Nurvidya Rachma Dewi ◽  
Ambrosius Purba ◽  
Beltasar Tarigan
Keyword(s):  
Physical Activity ◽  
Free Radicals ◽  
Cellular Level ◽  
Not Given ◽  
Time Intervals ◽  
Kolmogorov Smirnov ◽  
Group A ◽  
The Difference ◽  
Group B ◽  
Per Oral

Aerobic metabolism in the cellular level generates free radicals. Under normal condition,theres balance between free radicals and endogenous antioxidants. Excessive amount of freeradicals impair DNA, protein, fat, etc. The level of free radicals can be known by measuringplasma malondialdehyde level. Combination of Brastagis oranges and carrots juice asexogenous antioxidants supplementation expected to decrease free radicals level . The aim of thisstudy is to investigate the difference of plasma MDA level during several time intervals on micewhich is given and not given combination of Brastagis oranges and carrots juice before physicalactivity using mices treadmill for 20 minutes. The research method used in this study is anexperimental laboratory study. The objects of this study are 40 mice (mus musculus), whitecolored, male, weighting 25-30 grams, which is randomly chosen. The objects are divided into 2groups, Group A : 20 mice (given combination of Brastagis oranges and carrots juice beforephysical activity using mices treadmill) and group B : 20 mice (not given combination ofBrastagis oranges and carrots juice before physical activity using mices treadmill). Group Aare divided into 5 subgroups: A1 (measurement of plasma MDA level at 0 minute after treadmill),A2 (measurement of plasma MDA level at 15 minutes after treadmill), and A3 (measurement ofplasma MDA level at 30 minutes after treadmill), A4 (measurement of plasma MDA level at 60minutes after treadmill), and A5 (measurement of plasma MDA level at 240 minutes aftertreadmill). The same procedures are employed for the group B. Plasma MDA level measuredafter doing physical activity using mice treadmill. The homogenity of the result then was testedusing Levenes test and the normality of the result was tested using Kolmogorov-smirnov test (p>0.05). Further, the data was analyzed using independent t-test (p?0.05), one-way ANOVA(p?0.05) then Duncans test were used. The results reveal significant lowering plasma MDAconcentration in mice receiving combination of Brastagis oranges and carrots juice beforephysical activity, which is measured during several time intervals : 0,15,30,60, and 240 minutesafter physical activity than in mice not receiving combination of Brastagis oranges and carrotsjuice before physical activity. The MDA level differences between groups which is given and notgiven combination of Brastagis orange and carrots juice before physical activity measuredduring several intervals are 11,44% (0,8920 vs 1,0071) measured 0 minute after physical activity,15,47% (0,7902 vs 0,9348) measured 15 minutes after physical activity, 14,42% (0,7473 vs0,8732) measured 30 minutes after physical activity, 11,35% (0,6696 vs 0,7554) measured 60minutes after physical activity, and 13,60% (0,5786 vs 0,6696) measured 240 minutes afterphysical activity.The conclusion of the study suggested that combination of Brastagis orange andcarrots juice supplementation has lowering effect toward plasma MDA level measured duringseveral time intervals.

scholarly journals Membrane cofactor protein (CD46) protects cells from complement-mediated attack by an intrinsic mechanism.

1992 ◽  
Vol 175 (6) ◽  
pp. 1547-1551 ◽  
Author(s):  
T J Oglesby ◽  
C J Allen ◽  
M K Liszewski ◽  
D J White ◽  
J P Atkinson
Keyword(s):  
Protective Role ◽  
Cellular Level ◽  
Host Cells ◽  
Membrane Cofactor Protein ◽  
Alternative Pathways ◽  
Intrinsic Mechanism ◽  
Dose Dependent Fashion ◽  
Mouse Cells ◽  
Nih 3T3 ◽  
Relationship Of

The cleavage of C3 is a critical step for complement (C) activation in the classical and alternative pathways. This reaction is controlled by the regulators of C activation protein family. Membrane cofactor protein (MCP) is a cofactor for the factor I-mediated inactivation of C3b and C4b. As a widely distributed membrane protein, MCP may protect host cells from inadvertent C activation. Human MCP has recently been shown to protect transfected rodent cells from human C-mediated lysis. In this report the relationship of MCP expression to C3b deposition and cytoprotection was examined using NIH/3T3 cells transfected with human MCP and exposed to human serum as a source of C and naturally occurring anti-mouse antibody. MCP inhibited C3b deposition in a dose-dependent fashion and inhibited lysis of the mouse cells expressing it. MCP did not inhibit lysis on bystander cells. These results demonstrate the protective role of MCP, at the cellular level, by an intrinsic mechanism.

scholarly journals Impact of Salmonella enterica Type III Secretion System Effectors on the Eukaryotic Host Cell

2012 ◽  
Vol 2012 ◽  
pp. 1-36 ◽  
Author(s):  
Francisco Ramos-Morales
Keyword(s):  
Type Iii Secretion ◽  
Salmonella Enterica ◽  
Current Knowledge ◽  
Cellular Level ◽  
Host Cells ◽  
Secretion Systems ◽  
Type Iii ◽  
Cellular Processes ◽  
Type Iii Secretion Systems ◽  
Near Future

Type III secretion systems are molecular machines used by many Gram-negative bacterial pathogens to inject proteins, known as effectors, directly into eukaryotic host cells. These proteins manipulate host signal transduction pathways and cellular processes to the pathogen’s advantage. Salmonella enterica possesses two virulence-related type III secretion systems that deliver more than forty effectors. This paper reviews our current knowledge about the functions, biochemical activities, host targets, and impact on host cells of these effectors. First, the concerted action of effectors at the cellular level in relevant aspects of the interaction between Salmonella and its hosts is analyzed. Then, particular issues that will drive research in the field in the near future are discussed. Finally, detailed information about each individual effector is provided.

scholarly journals 1,2,3,4,6-Pentagalloyl Glucose, a RBD-ACE2 Binding Inhibitor to Prevent SARS-CoV-2 Infection

2021 ◽  
Vol 12 ◽  
Author(s):  
Rui Hong Chen ◽  
Li Jun Yang ◽  
Sami Hamdoun ◽  
Sookja Kim Chung ◽  
Christopher Wai-kei Lam ◽  
...  
Keyword(s):  
Antiviral Agent ◽  
Face Mask ◽  
Storage Condition ◽  
Cellular Level ◽  
Host Cells ◽  
Hek293 Cells ◽  
Global Public Health ◽  
Angiotensin Converting Enzyme 2 ◽  
Novel Drugs ◽  
Pentagalloyl Glucose

The outbreak of SARS-CoV-2 virus caused more than 80,155,187 confirmed COVID-19 cases worldwide, which has posed a serious threat to global public health and the economy. The development of vaccines and discovery of novel drugs for COVID-19 are urgently needed. Although the FDA-approved SARS-CoV-2 vaccines has been launched in many countries recently, the strength of safety, stringent storage condition and the possibly short-term immunized efficacy remain as the major challenges in the popularity and recognition of using vaccines against SARS-CoV-2. With the spike-receptor binding domain (RBD) of SARS-CoV-2 being responsible for binding to human angiotensin-converting enzyme 2 receptor (hACE2), ACE2 is identified as the receptor for the entry and viral infection of SARS-CoV-2. In this study, molecular docking and biolayer interferometry (BLI) binding assay were adopted to determine the direct molecular interactions between natural small-molecule, 1,2,3,4,6-Pentagalloyl glucose (PGG) and the spike-RBD of the SARS-CoV-2. Our results showed that PGG preferentially binds to a pocket that contains residues Glu 340 to Lys 356 of spike-RBD with a relatively low binding energy of -8 kcal/mol. BLI assay further confirmed that PGG exhibits a relatively strong binding affinity to SARS-CoV-2-RBD protein in comparison to hACE2. In addition, both ELISA and immunocytochemistry assay proved that PGG blocks SARS-CoV-2-RBD binding to hACE2 dose dependently in cellular level. Notably, PGG was confirmed to abolish the infectious property of RBD-pseudotyped lentivirus in hACE2 overexpressing HEK293 cells, which mimicked the entry of wild type SARS-CoV-2 virus in human host cells. Finally, maximal tolerated dose (MTD) studies revealed that up to 200 mg/kg/day of PGG was confirmed orally safe in mice. Our findings suggest that PGG may be a safe and potential antiviral agent against the COVID-19 by blockade the fusion of SARS-CoV-2 spike-RBD to hACE2 receptors. Therefore, PGG may be considered as a safe and natural antiviral agent for its possible preventive application in daily anti-virus hygienic products such as a disinfectant spray or face mask.

scholarly journals Histological Variation in Plethodontid Digital Surfaces [University of Findlay]

2019 ◽  
Author(s):  
Megan Pasternak ◽  
Justin Rheubert
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Surface Morphology ◽  
Light Microscopy ◽  
Morphological Evolution ◽  
Ventral Surface ◽  
Cellular Level ◽  
Plethodontid Salamanders ◽  
And Function ◽  
Scanning Electron

Despite numerous investigations into the morphology and function of toe pads in many species, most notably anurans and geckonids, there is relatively little knowledge on salamander digit morphology. To date, toe morphology in salamanders has been limited to Desmognathus fuscus, Ambystoma maculatum, Bolitoglossa sp., and Aneides aeneus. The limited studies to date have shown variation inter- and intra-specifically but have not investigated numerous taxa within a given family which may provide deeper insights into the causes of variation (phylogenetic vs ecological pressures). Therefore, to test hypotheses concerning the presence of variation in the ventral digital surface of plethodontid salamanders, we plan to use various microscopy methodologies to view the ventral surface of the digital tips of three species from three different genera within the Plethodontidae: Desmognathus, Eurycea, and Plethodon. Toe pads will be characterized grossly using scanning electron microscopy, histologically using light microscopy, and ultrastructurally using transmission electron microscopy. Preliminary results suggest that all three species investigated display enlarged surfaces. Surface morphology (assessed via scanning electron microscopy) varies between species at a gross level concerning the shape and overall orientation of the enlarged surface. Surface morphologies include a well-developed circular pad (D. fuscus), a well-developed oval pad (P. cinereus), and a poorly developed circular pad (E. cirrigera). Furthermore, surface morphology appears to vary at the cellular level as well, with Desmognathus having polygonal squamous cells with microprojections and Eurycea having polygonal cells with nanopillars in a honeycomb arrangement. These differences may be attributed to differences in habitat preference as the three species tested include a terrestrial, semi-aquatic, and aquatic dwelling species. However, further investigation including light microscopy and enhanced scanning electron microscopy are needed. Further understanding of the morphological variation will aid in our understanding of ecomorphology and understanding of morphological evolution in amphibians.

scholarly journals Shiga Toxins as Antitumor Tools

Toxins ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 690
Author(s):  
Aude Robert ◽  
Joëlle Wiels
Keyword(s):  
Cellular Level ◽  
Shigella Dysenteriae ◽  
Host Cells ◽  
Health Concern ◽  
28S Rrna ◽  
Shiga Toxins ◽  
Unfolded Protein ◽  
Efficient Delivery ◽  
Uremic Syndrome ◽  
Protein Response

Shiga toxins (Stxs), also known as Shiga-like toxins (SLT) or verotoxins (VT), constitute a family of structurally and functionally related cytotoxic proteins produced by the enteric pathogens Shigella dysenteriae type 1 and Stx-producing Escherichia coli (STEC). Infection with these bacteria causes bloody diarrhea and other pathological manifestations that can lead to HUS (hemolytic and uremic syndrome). At the cellular level, Stxs bind to the cellular receptor Gb3 and inhibit protein synthesis by removing an adenine from the 28S rRNA. This triggers multiple cellular signaling pathways, including the ribotoxic stress response (RSR), unfolded protein response (UPR), autophagy and apoptosis. Stxs cause several pathologies of major public health concern, but their specific targeting of host cells and efficient delivery to the cytosol could potentially be exploited for biomedical purposes. Moreover, high levels of expression have been reported for the Stxs receptor, Gb3/CD77, in Burkitt’s lymphoma (BL) cells and on various types of solid tumors. These properties have led to many attempts to develop Stxs as tools for biomedical applications, such as cancer treatment or imaging, and several engineered Stxs are currently being tested. We provide here an overview of these studies.

scholarly journals Edwardsiella tarda Eta1, anIn Vivo-Induced Antigen That Is Involved in Host Infection

2012 ◽  
Vol 80 (8) ◽  
pp. 2948-2955 ◽  
Author(s):  
Yun Sun ◽  
Wen-Jiang Zheng ◽  
Yong-Hua Hu ◽  
Bo-Guang Sun ◽  
Li Sun
Keyword(s):  
Early Stage ◽  
Paralichthys Olivaceus ◽  
Cellular Level ◽  
Host Cells ◽  
Edwardsiella Tarda ◽  
Pcr Analysis ◽  
Logarithmic Phase ◽  
Content Type

ABSTRACTEdwardsiella tarda, a Gram-negative bacterium, is a severe fish pathogen that can also infect humans. In this study, we identified, viain vivo-induced antigen technology, anE. tardaantigen, Eta1, and analyzed its function in a Japanese flounder (Paralichthys olivaceus) model. Eta1 is composed of 226 residues and shares homology with putative bacterial adhesins. Quantitative real-time reverse transcriptase (RT)-PCR analysis indicated that when culturedin vitro,eta1expression was growth phase dependent and reached maximum at mid-logarithmic phase. During infection of flounder lymphocytes,eta1expression was drastically increased at the early stage of infection. Compared to the wild type, theeta1-defective mutant, TXeta1, was unaffected in growth but exhibited attenuated overall virulence, reduced tissue dissemination and colonization capacity, and impaired ability to invade flounder lymphocytes and to block the immune response of host cells. The lost virulence of TXeta1 was restored when a functionaleta1gene was reintroduced into the strain. Western blot and immunodetection analyses showed that Eta1 is localized to the outer membrane and exposed on the surface ofE. tardaand that recombinant Eta1 (rEta1) was able to interact with flounder lymphocytes. Consistent with these observations, antibody blocking of Eta1 inhibitedE. tardainfection at the cellular level. Furthermore, when used as a subunit vaccine, rEta1 induced strong protective immunity in flounder against lethalE. tardachallenge. Taken together, these results indicate that Eta1 is anin vivo-induced antigen that mediates pathogen-host interaction and, as a result, is required for optimal bacterial infection.

Organization and composition of the cytoskeleton of giant algal cells: Its role in wound healing

1989 ◽  
Vol 47 ◽  
pp. 752-753
Author(s):  
R. H. Goddard ◽  
J. W. La Claire II
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Wound Healing ◽  
Light Microscopy ◽  
Cellular Level ◽  
Model System ◽  
Functional Roles ◽  
Transmission Electron ◽  
New Findings ◽  
Secondary Antibodies

We have been using the giant algal cells of Ernodesmis verticillata as a model system to study the process of wound healing at the cellular level of organization. Using immuno-localization techniques we have observed changes in the distribution of tubulin-containing microtubules (MTs) and actin-containing microfilaments (MFs), that occur during wound healing. Based on these and new findings, we carried out correlative experiments with inhibitors to investigate the functional roles of the various cytoskeletal components in wound healing.Emodesmis cells were cultured, Wounded and Fixed as described previously. The cytoplasm from fixed cells was adhered to polylysine-coated coverslips for light microscopy, or to formvar coated gold grids for transmission electron microscopy (TEM).The attached cells were labeled with primary antibodies (against tubulin ,actin,calmodulin [CAM], intermediate filament [If] proteins, or myosin)followed by incubation in appropriate secondary antibodies conjugated with FITC or TRITC for fluorescence, or conjugated to gold beads for TEM.

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