Suppression of Canola (Brassica napus) Resistance by Virulent Isolates of Plasmodiophora brassicae (Clubroot) During Primary Infection

The planting of clubroot resistant (CR) canola (Brassica napus) is the most effective method to manage clubroot. Since 2013, many Plasmodiophora brassicae isolates capable of overcoming resistance have been detected, often in mixtures with avirulent isolates. To improve understanding of the effect of low concentrations of virulent isolates on host resistance, three CR canola cultivars (45H29, L135C, and L241C) were inoculated with pairs of isolates representing virulent/avirulent pathotypes (2*/2, 3*/3, and 5*/5) collected after or before the introduction of CR canola, respectively. Seven-day-old seedlings of each cultivar were incubated for 2 days in low concentrations (1 × 103 spores/ml) of the virulent isolates, followed by a second inoculation with a high concentration (1 × 107 spores/ml) of the avirulent isolates. Positive controls comprised seedlings inoculated with low concentrations of the virulent isolates followed by high concentrations of the virulent isolates (PC1) or only with high concentrations of virulent isolates (PC2). Negative controls comprised seedlings inoculated only with high concentrations of the avirulent isolates (NC1) or only with low concentrations of the virulent isolates (NC2). Clubroot severity was significantly higher in all nine experimental treatments (low virulent plus high avirulent) than in the negative control NC1 (high avirulent) but was lower in the experimental treatments than in the positive controls (PC1 and PC2). Low concentrations of virulent isolates alone (NC2) caused moderate clubroot. Disease severity correlated well with P. brassicae biomass in canola as determined by quantitative PCR analysis 28 to 35 days after inoculation. This study revealed that low concentrations of virulent isolates compromised canola resistance for infection by avirulent isolates.

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Vascular responses to compound 48/80 in rat mesenteric vascular beds

Canadian Journal of Physiology and Pharmacology ◽

10.1139/cjpp-2015-0442 ◽

2016 ◽

Vol 94 (6) ◽

pp. 620-626 ◽

Cited By ~ 1

Author(s):

Honghua Jin ◽

Zhen Li ◽

Shingo Takatori ◽

Toshihiro Koyama ◽

Xin Jin ◽

...

Keyword(s):

Mast Cells ◽

Ruthenium Red ◽

High Concentration ◽

Phase 3 ◽

Vascular Effect ◽

Vascular Responses ◽

Endogenous Histamine ◽

Low Concentrations ◽

Vascular Beds ◽

High Concentrations

A further investigation was performed on the vascular effect of endogenous histamine using the histamine releaser, compound 48/80, in rat mesenteric vascular beds with active tone. In preparations with intact endothelium, low concentrations of compound 48/80 (1.53 × 10−5 – 3 × 1.53 × 10−5 mg/mL) perfusion for 1 min only induced a small vasodilation. High concentrations of compound 48/80 (1.53 × 10−4 – 3 × 1.53 × 10−2 mg/mL) induced a biphasic vascular responses, an initial vasoconstriction followed a subsequent long-lasting vasodilation. The vasodilation induced by low concentrations of compound 48/80 and the vasoconstriction induced by high concentration of compound 48/80 was inhibited by olopatadine. However, cimetidine did not affect the responses induced by compound 48/80. Endothelium removal enlarged the compound 48/80-induced phase-2 vasoconstriction, while it attenuated the phase-3 vasodilation. Additionally, indomethacin and seratrodast significantly inhibited vasoconstriction but it did not affect the long-lasting vasodilation induced by high concentrations of compound 48/80. Ruthenium red inhibited the vasodilation induced by low concentrations and high concentrations of compound 48/80. These results suggest that the vasoconstriction induce by high concentrations of compound 48/80 is mediated by endogenous histamine released from mast cells. It is also suggested that thromboxane A2 released from mast cells is related to the vasoconstriction.

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Biphasic Effect of Pirfenidone on Angiogenesis

Frontiers in Pharmacology ◽

10.3389/fphar.2021.804327 ◽

2022 ◽

Vol 12 ◽

Author(s):

Donghao Gan ◽

Wenxiang Cheng ◽

Liqing Ke ◽

Antonia RuJia Sun ◽

Qingyun Jia ◽

...

Keyword(s):

Vascular Endothelial Cells ◽

Tube Formation ◽

Endothelial Cell Migration ◽

High Concentration ◽

Low Concentrations ◽

Biphasic Effect ◽

High Concentrations ◽

And Migration ◽

The Impact

Pirfenidone (PFD), a synthetic arsenic compound, has been found to inhibit angiogenesis at high concentrations. However, the biphasic effects of different PFD concentrations on angiogenesis have not yet been elucidated, and the present study used an in vitro model to explore the mechanisms underlying this biphasic response. The effect of PFD on the initial angiogenesis of vascular endothelial cells was investigated through a Matrigel tube formation assay, and the impact of PFD on endothelial cell migration was evaluated through scratch and transwell migration experiments. Moreover, the expression of key migration cytokines, matrix metalloproteinase (MMP)-2 and MMP-9, was examined. Finally, the biphasic mechanism of PFD on angiogenesis was explored through cell signaling and apoptosis analyses. The results showed that 10–100 μM PFD has a significant and dose-dependent inhibitory effect on tube formation and migration, while 10 nM–1 μM PFD significantly promoted tube formation and migration, with 100 nM PFD having the strongest effect. Additionally, we found that a high concentration of PFD could significantly inhibit MMP-2 and MMP-9 expression, while low concentrations of PFD significantly promoted their expression. Finally, we found that high concentrations of PFD inhibited EA.hy926 cell tube formation by promoting apoptosis, while low concentrations of PFD promoted tube formation by increasing MMP-2 and MMP-9 protein expression predominantly via the EGFR/p-p38 pathway. Overall, PFD elicits a biphasic effect on angiogenesis through different mechanisms, could be used as a new potential drug for the treatment of vascular diseases.

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Genistein Inhibits Cell Proliferation and Induces Mitochondrial and Nuclear Alterations That Indicate Mechanisms Involved in Apoptosis

Microscopy and Microanalysis ◽

10.1017/s1431927600036746 ◽

2000 ◽

Vol 6 (S2) ◽

pp. 850-851

Author(s):

Geoffrey Gobert ◽

Ed Curren ◽

Wade Welshons ◽

Qing-yuan Sun ◽

Heide Schatten

Keyword(s):

Breast Cancer ◽

Cell Proliferation ◽

Tyrosine Kinases ◽

High Concentration ◽

Transmission Electron ◽

Low Concentrations ◽

Culture Models ◽

High Concentrations ◽

Underlying Mechanisms ◽

Nuclear Alterations

A highly significant correlation between reduced incidence of breast cancer in Asian countries and consumption of soy suggests that specific components in soy may have anticarcinogen activity. The soy ingredients genistein and daidzein have been found to inhibit induced breast tumors in animal and cell culture models. These isoflavones are known to be both agonists and antagonists of estrogen activity but only genistein is also a potent inhibitor of tyrosine kinases which are the primary intracellular signalling mechanisms associated with the regulation of cell proliferation.Genistein promotes cell proliferation in breast cancer cells at low concentrations in its function as estrogen agonist but inhibits cell proliferation at high concentrations (30 μM). In order to investigate the underlying mechanisms by which high concentration of genistein inhibit cell proliferation we treated MCF-7 cells with increasing concentrations of genistein and analyzed cells by immunofluorescence and transmission electron microscopy (TEM).

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Genetics and molecular mapping of resistance to Plasmodiophora brassicae pathotypes 2, 3, 5, 6, and 8 in rutabaga (Brassica napus var. napobrassica)

Genome ◽

10.1139/gen-2016-0034 ◽

2016 ◽

Vol 59 (10) ◽

pp. 805-815 ◽

Cited By ~ 24

Author(s):

Muhammad Jakir Hasan ◽

Habibur Rahman

Keyword(s):

Brassica Napus ◽

Doubled Haploid ◽

Genetic Basis ◽

Molecular Mapping ◽

Plasmodiophora Brassicae ◽

Single Gene ◽

Genomic Region ◽

Clubroot Disease ◽

Dh Population ◽

Brassica Crops

Clubroot disease, caused by Plasmodiophora brassicae, is a threat to the production of Brassica crops including oilseed B. napus. In Canada, several pathotypes of this pathogen, such as pathotypes 2, 3, 5, 6, and 8, were identified, and resistance to these pathotypes was found in a rutabaga (B. napus var. napobrassica) genotype. In this paper, we report the genetic basis and molecular mapping of this resistance by use of F2, backcross (BC1), and doubled haploid (DH) populations generated from crossing of this rutabaga line to a susceptible spring B. napus canola line. The F1, F2, and BC1 populations were evaluated for resistance to pathotype 3, and the DH population was evaluated for resistance to pathotypes 2, 3, 5, 6, and 8. A 3:1 segregation in F2 and a 1:1 segregation in BC1 were found for resistance to pathotype 3, and a 1:1 segregation was found in the DH population for resistance to all pathotypes. Molecular mapping by using the DH population identified a genomic region on chromosome A8 carrying resistance to all five pathotypes. This suggests that a single gene or a cluster of genes, located in this genomic region, is involved in the control of resistance to these pathotypes.

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Real-Time, Label-Free Detection of Local Exocytosis Outside Pancreatic β Cells Using Laser Tweezers Raman Spectroscopy

Applied Spectroscopy ◽

10.1177/0003702816670911 ◽

2016 ◽

Vol 71 (3) ◽

pp. 422-431 ◽

Cited By ~ 2

Author(s):

Rui-qiong Luo ◽

Fang Wei ◽

Shu-shi Huang ◽

Yue-ming Jiang ◽

Shan-lei Zhang ◽

...

Keyword(s):

Raman Spectroscopy ◽

Negative Control ◽

Laser Tweezers ◽

Channel Blockers ◽

Label Free ◽

Β Cells ◽

Pancreatic Β Cells ◽

Low Concentrations ◽

Label Free Detection ◽

High Concentrations

The examination of insulin (Ins) exocytosis at the single-cell level by conventional methods, such as electrophysiological approaches, total internal reflection imaging, and two-photon imaging technology, often requires an invasive microelectrode puncture or label. In this study, high concentrations of glucose and potassium chloride were used to stimulate β cell Ins exocytosis, while low concentrations of glucose and calcium channel blockers served as the blank and negative control, respectively. Laser tweezers Raman spectroscopy (LTRS) was used to capture the possible Raman scattering signal from a local zone outside of the cell edge. The results show that the frequencies of the strong signals from the local zones outside the cellular edge in the stimulated groups are greater than those of the control. The Raman spectra from the cellular edge, Ins and cell membrane were compared. Thus, local Ins exocytosis activity outside pancreatic β cells might be observed indirectly using LTRS, a non-invasive optical method.

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Identification of Micro Ribonucleic Acids and Their Targets in Response to Plasmodiophora brassicae Infection in Brassica napus

Frontiers in Plant Science ◽

10.3389/fpls.2021.734419 ◽

2021 ◽

Vol 12 ◽

Author(s):

Qian Li ◽

Nadil Shah ◽

Xueqing Zhou ◽

Huiying Wang ◽

Wenlin Yu ◽

...

Keyword(s):

Brassica Napus ◽

Mirna Target ◽

Plasmodiophora Brassicae ◽

Signal Transduction Pathway ◽

Pathogen Resistance ◽

Small Rna Sequencing ◽

Hypersensitive Cell Death ◽

Significant Differential Expression ◽

Clubroot Disease ◽

Ribonucleic Acids

Clubroot disease, which is caused by the soil-borne pathogen Plasmodiophora brassicae War (P. brassicae), is one of the oldest and most destructive diseases of Brassica and cruciferous crops in the world. Plant microRNAs [micro ribonucleic acids (miRNAs)] play important regulatory roles in several developmental processes. Although the role of plant miRNAs in plant-microbe interaction has been extensively studied, there are only few reports on the specific functions of miRNAs in response to P. brassicae. This study investigated the roles of miRNAs and their targets during P. brassicae infection in a pair of Brassica napus near-isogenic lines (NILs), namely clubroot-resistant line 409R and clubroot-susceptible line 409S. Small RNA sequencing (sRNA-seq) and degradome-seq were performed on root samples of 409R and 409S with or without P. brassicae inoculation. sRNA-seq identified a total of 48 conserved and 72 novel miRNAs, among which 18 had a significant differential expression in the root of 409R, while only one miRNA was differentially expressed in the root of 409S after P. brassicae inoculation. The degradome-seq analysis identified 938 miRNA target transcripts, which are transcription factors, enzymes, and proteins involved in multiple biological processes and most significantly enriched in the plant hormone signal transduction pathway. Between 409R and 409S, we found eight different degradation pathways in response to P. brassicae infection, such as those related to fatty acids. By combining published transcriptome data, we identified a total of six antagonistic miRNA-target pairs in 409R that are responsive to P. brassicae infection and involved in pathways associated with root development, hypersensitive cell death, and chloroplast metabolic synthesis. Our results reveal that P. brassicae infection leads to great changes in miRNA pool and target transcripts. More interestingly, these changes are different between 409R and 409S. Clarification of the crosstalk between miRNAs and their targets may shed new light on the possible mechanisms underlying the pathogen resistance against P. brassicae.

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Heavy metals uptake by hyperaccumulating flora in some serpentine soils of Kosovo

Global NEST Journal ◽

10.30955/gnj.001804 ◽

2016 ◽

Vol 18 (1) ◽

pp. 214-222 ◽

Cited By ~ 5

Keyword(s):

Heavy Metals ◽

Ultramafic Rocks ◽

Metamorphic Rocks ◽

Serpentine Soils ◽

High Concentration ◽

Important Indicator ◽

Low Concentrations ◽

Close Relationship ◽

High Concentrations ◽

Heavy Metals Uptake

Ultramafics represent magmatic or metamorphic rocks which are characterized by high concentrations of Mg, Fe, Ni, Cr and Co and low concentrations of Ca, and K. Serpentine soils are weathered products of a range of ultramafic rocks composed of ferromagnesian silicates. The aim of this study was to determine the content of heavy metals in some of serpentine soils of Kosovo and heavy metals uptake by entire associated flora. Furthermore, another objective of this study was finding out bioavailable Ca/Mg relationship, which is very important indicator for plants’ development. The sampling was conducted in June 2014. A total of three serpentine areas have been surveyed and 7 soil samples have been taken in various depths of soil profiles. Those samples were analyzed for total Ca, Cd, Co, Cr, Cu, Mn, Ni, Pb, Fe and Zn. Results showed that each site exhibited a high concentration of at least one metal. The maximum concentrations of metals in soils Dry Matter (DM) were 108.9 mg kg-1 Cd, 95.8 mg kg-1 Co, 1206 mg kg-1 Cr, 24 mg kg-1 Cu, 2570 mg kg-1 Ni, 21.7 mg kg-1 Pb, 39 mg kg-1 Zn, and 51563 mg kg- Fe. The serpentine soils at all sites were characterized by elevated levels of heavy metals, which showed typical properties of ultramafic environments. Nickel Total at studied areas varied between 1543 and 2570 mg kg-1, while the highest Ni concentration was found in aerial part of Alyssum markgrafii (4038 mgkg-1), <div> Based on our findings on the field we concluded that there is a close relationship between the quantity of Ni in soil and Ni uptake in plants. </div>

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Receptors involved in helodermin action on rat pancreatic acini

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1986.251.5.g602 ◽

1986 ◽

Vol 251 (5) ◽

pp. G602-G610 ◽

Cited By ~ 1

Author(s):

J. P. Dehaye ◽

J. Winand ◽

C. Damien ◽

F. Gomez ◽

P. Poloczek ◽

...

Keyword(s):

Protein Phosphorylation ◽

Amylase Secretion ◽

High Concentration ◽

Amylase Release ◽

Pancreatic Acini ◽

Heloderma Suspectum ◽

Low Concentrations ◽

High Concentrations ◽

Camp Levels ◽

Camp Elevation

Helodermin is a new peptide isolated from the venom of Heloderma suspectum. Its effects on rat pancreatic acini were compared with those of secretin and vasoactive intestinal peptide (VIP). Four classes of receptors with decreasing affinity for secretin (S1, S2, S3, and S4) were first delineated. Occupancy of S1 and S2 by secretin was responsible for a biphasic adenosine 3',5'-cyclic monophosphate (cAMP) response. S3 was VIP preferring so that the VIP-induced increase in cAMP could be inhibited by VIP-(10 --28). S2 and S3 allowed cAMP elevation, protein phosphorylation, weak secretory effects, and potentiation of cholecystokinin octapeptide (CCK-8) when occupied by secretin and VIP, respectively. A more efficient exocytosis was observed with secretin interacting with low-affinity receptors S4. Helodermin increased cAMP levels 14-fold, this increase being inhibited by VIP-(10–28). Low concentrations of helodermin stimulated amylase secretion twofold and potentiated secretion by CCK-8. High concentrations of helodermin stimulated secretion another 2.6-fold. Helodermin bound to the four secretin receptors with a weak selectivity. At low concentration, helodermin stimulated cAMP elevation, protein phosphorylation, amylase release, and potentiation of CCK-8 through S3, whereas at high concentration it stimulated secretion via S4.

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Effect of canola (Brassica napus) cultivar rotation on Plasmodiophora brassicae pathotype composition

Canadian Journal of Plant Science ◽

10.1139/cjps-2019-0126 ◽

2020 ◽

Vol 100 (2) ◽

pp. 218-225 ◽

Cited By ~ 2

Author(s):

Tiesen Cao ◽

Victor P. Manolii ◽

Qixing Zhou ◽

Sheau-Fang Hwang ◽

Stephen E. Strelkov

Keyword(s):

Brassica Napus ◽

Quantitative Pcr ◽

Plasmodiophora Brassicae ◽

Pcr Analysis ◽

Susceptible Cultivar ◽

Specific Primers ◽

Greenhouse Experiments ◽

Pathogen Populations ◽

Soil Mix ◽

The Impact

In Canada, clubroot (Plasmodiophora brassicae) disease is managed mainly by planting clubroot resistant (CR) canola (Brassica napus). New pathotypes of P. brassicae have emerged recently, however, which are virulent on most CR canola cultivars. To understand the impact of cultivar rotation on pathotype abundance, greenhouse experiments were conducted in which different canola cultivar rotations were grown in a soil mix containing equal amounts of pathotypes 5X and 3, which are virulent and avirulent, respectively, on CR canola. The rotation treatments included: T1, the same susceptible cultivar planted over four cycles; T2, the same CR cultivar planted over four cycles; and T3, different CR cultivars planted in each cycle. Clubroot severity increased from cycles one to four in all treatments, with the exception of one CR cultivar in T3 that may carry a different source of resistance. Pathogen populations were recovered with a susceptible bait crop and pathotyped on the differentials of Williams plus a CR host (B. napus ‘Mendel’). The percentage of galls classified as pathotype 5X in T1 declined from 50% to 6.7% over the course of the experiment, while galls classified as pathotype 5X increased from 50% to 66.7% in both T2 and T3. Quantitative PCR analysis of the soil with pathotype 5X-specific primers generally confirmed an increase in 5X DNA. The results suggest that continuous planting of CR canola favours a rapid proliferation of virulent pathotypes of P. brassicae, as indicated by the increases in pathotype 5X observed in this study.

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