Molecular interactions of victorin and oats

1995 ◽  
Vol 73 (S1) ◽  
pp. 475-482 ◽  
Author(s):  
D. A. Navarre ◽  
J. M. Lorang ◽  
D. L. Moore ◽  
T. J. Wolpert
Keyword(s):  
Protein A ◽  
Glyoxylic Acid ◽  
Biologically Active ◽  
Glycine Decarboxylase ◽  
Putative Toxin ◽  
Toxin Receptor ◽  
Blight Of Oats

We have been investigating a disease called victoria blight of oats, which is caused by the fungus Cochliobolus victoriae. The fungus is pathogenic because of its ability to produce the host-selective toxin, victorin. Victorin is composed of a group of structurally related cyclized pentapeptides. The most abundant component of victorin in culture filtrates, victorin C, has a molecular weight of 814 and is composed of glyoxylic acid, 5,5-dichloroleucine, threo-β-hydroxylysine, erythro-β-hydroxyleucine, α-amino-β-chloroacrylic acid, and 2-alanyl-3,5-dihydroxy-⌂2-cyclopentenone-1. Sensitivity to victorin, and thus, susceptibility to the fungus, is controlled by a dominant allele at the Vb locus. Furthermore, the Vb gene is either closely linked or identical to the Pc-2 gene, which confers resistance to the crown rust pathogen Puccinia coronata. Thus, it is anticipated that identification of the product of the Vb gene, a putative toxin receptor, will simultaneously identify the product of the Pc-2 rust resistance gene. We have identified two proteins, referred to as victorin binding proteins (VBP), which bind biologically active, radiolabelled victorin in vivo. One protein, a 100-kDa VBP, binds victorin in vivo only in toxin-sensitive, susceptible genotypes. The other VBP, a 15-kDa protein, binds victorin in vivo in both susceptible and resistant genotypes. We have isolated and characterized the 100-kDa VBP and have recently identified, in vitro, a 15-kDa VBP. Both of these proteins are components of the multienzyme complex, glycine decarboxylase. Current investigations center on the role of this enzyme complex in toxin sensitivity. Key words: victorin, oats, toxin, glycine decarboxylase, resistance, susceptibility.

scholarly journals In vitro and in vivo evidence for an inflammatory role of the calcium channel TRPV4 in lung epithelium: Potential involvement in cystic fibrosis

2016 ◽  
Vol 311 (3) ◽  
pp. L664-L675 ◽  
Author(s):  
Clémence O. Henry ◽  
Emilie Dalloneau ◽  
Maria-Teresa Pérez-Berezo ◽  
Cristina Plata ◽  
Yongzheng Wu ◽  
...  
Keyword(s):  
Cystic Fibrosis ◽  
Calcium Channel ◽  
Lung Inflammation ◽  
Transient Receptor Potential ◽  
Biologically Active ◽  
Transient Receptor Potential Vanilloid ◽  
Anti Inflammatory

Cystic fibrosis (CF) is an inherited disease associated with chronic severe lung inflammation, leading to premature death. To develop innovative anti-inflammatory treatments, we need to characterize new cellular and molecular components contributing to the mechanisms of lung inflammation. Here, we focused on the potential role of “transient receptor potential vanilloid-4” (TRPV4), a nonselective calcium channel. We used both in vitro and in vivo approaches to demonstrate that TRPV4 expressed in airway epithelial cells triggers the secretion of major proinflammatory mediators such as chemokines and biologically active lipids, as well as a neutrophil recruitment in lung tissues. We characterized the contribution of cytosolic phospholipase A2, MAPKs, and NF-κB in TRPV4-dependent signaling. We also showed that 5,6-, 8,9-, 11,12-, and 14,15-epoxyeicosatrienoic acids, i.e., four natural lipid-based TRPV4 agonists, are present in expectorations of CF patients. Also, TRPV4-induced calcium mobilization and inflammatory responses were enhanced in cystic fibrosis transmembrane conductance regulator-deficient cellular and animal models, suggesting that TRPV4 is a promising target for the development of new anti-inflammatory treatments for diseases such as CF.

scholarly journals The bacterial chromatin protein HupA can remodel DNA and associates with the nucleoid in Clostridium difficile

2018 ◽  
Author(s):  
Ana M. Oliveira Paiva ◽  
Annemieke H. Friggen ◽  
Liang Qin ◽  
Roxanne Douwes ◽  
Remus T. Dame ◽  
...  
Keyword(s):  
Protein A ◽  
Chromatin Protein ◽  
Chromosomal Organization ◽  
Cellular Processes ◽  
Hu Proteins ◽  
Architectural Proteins ◽  
Chromatin Proteins

AbstractThe maintenance and organization of the chromosome plays an important role in the development and survival of bacteria. Bacterial chromatin proteins are architectural proteins that bind DNA, modulate its conformation and by doing so affect a variety of cellular processes. No bacterial chromatin proteins of C. difficile have been characterized to date.Here, we investigate aspects of the C. difficile HupA protein, a homologue of the histone-like HU proteins of Escherichia coli. HupA is a 10 kDa protein that is present as a homodimer in vitro and self-interacts in vivo. HupA co-localizes with the nucleoid of C. difficile. It binds to the DNA without a preference for the DNA G+C content. Upon DNA binding, HupA induces a conformational change in the substrate DNA in vitro and leads to compaction of the chromosome in vivo.The present study is the first to characterize a bacterial chromatin protein in C. difficile and opens the way to study the role of chromosomal organization in DNA metabolism and on other cellular processes in this organism.

scholarly journals Elucidating the Essential Role of the A14 Phosphoprotein in Vaccinia Virus Morphogenesis: Construction and Characterization of a Tetracycline-Inducible Recombinant

2000 ◽  
Vol 74 (8) ◽  
pp. 3682-3695 ◽  
Author(s):  
Paula Traktman ◽  
Ke Liu ◽  
Joseph DeMasi ◽  
Robert Rollins ◽  
Sophy Jesty ◽  
...  
Keyword(s):  
Vaccinia Virus ◽  
Protein A ◽  
Viral Gene ◽  
Large Numbers ◽  
Viral Morphogenesis ◽  
Translational Start

ABSTRACT We have previously reported the construction and characterization of vindH1, an inducible recombinant in which expression of the vaccinia virus H1 phosphatase is regulated experimentally by IPTG (isopropyl-β-d-thiogalactopyranoside) (35). In the absence of H1 expression, the transcriptional competence and infectivity of nascent virions are severely compromised. We have sought to identify H1 substrates by characterizing proteins that are hyperphosphorylated in H1-deficient virions. Here, we demonstrate that the A14 protein, a component of the virion membrane, is indeed an H1 phosphatase substrate in vivo and in vitro. A14 is hyperphosphorylated on serine residues in the absence of H1 expression. To enable a genetic analysis of A14's function during the viral life cycle, we have adopted the regulatory components of the tetracycline (TET) operon and created new reagents for the construction of TET-inducible vaccinia virus recombinants. In the context of a virus expressing the TET repressor (tetR), insertion of the TET operator between the transcriptional and translational start sites of a late viral gene enables its expression to be tightly regulated by TET. We constructed a TET-inducible recombinant for the A14 gene, vindA14. In the absence of TET, vindA14 fails to form plaques and the 24-h yield of infectious progeny is reduced by 3 orders of magnitude. The infection arrests early during viral morphogenesis, with the accumulation of large numbers of vesicles and the appearance of “empty” crescents that appear to adhere only loosely to virosomes. This phenotype corresponds closely to that observed for an IPTG-inducible A14 recombinant whose construction and characterization were reported while our work was ongoing (47). The consistency in the phenotypes seen for the IPTG- and TET-inducible recombinants confirms the efficacy of the TET-inducible system and reinforces the value of having a second, independent system available for generating inducible recombinants.

scholarly journals D-Chiro-Inositol Improves Sperm Mitochondrial Membrane Potential: In Vitro Evidence

2020 ◽  
Vol 9 (5) ◽  
pp. 1373 ◽  
Author(s):  
Rosita A. Condorelli ◽  
Federica Barbagallo ◽  
Aldo E. Calogero ◽  
Rossella Cannarella ◽  
Andrea Crafa ◽  
...  
Keyword(s):  
Membrane Potential ◽  
Mitochondrial Membrane Potential ◽  
Sperm Motility ◽  
Mitochondrial Membrane ◽  
Polycystic Ovarian Syndrome ◽  
Biologically Active ◽  
Ovarian Syndrome

The use of inositols in endocrinological clinical practice is increasingly widespread. Most of the existing evidence concerns myoinositol (MYO), the most abundant form in nature, especially in women with polycystic ovarian syndrome. We have previously shown that MYO increases sperm motility in patients with asthenozoospermia by the increase of sperm mitochondrial membrane potential (MMP), a biofunctional sperm parameter closely associated to sperm motility. The aim of this study was to evaluate the effects of D-chiro-inositol (DCI), another biologically active isoform of inositols, on sperm MMP, as data on this matter has never been released so far. To accomplish this, semen samples from 15 patients with asthenozoospermia and 15 healthy normozoospermic men were incubated with increasing concentrations of DCI (0, 75, and 750 µg/mL) or phosphate buffer saline for 30 min. Incubation with DCI significantly improved sperm MMP at lower concentrations, and with shorter incubation length than those used in our similar MYO studies. In conclusion, these findings indicate that DCI positively impacts on sperm mitochondrial function in vitro. Studies aimed at assessing the role of DCI in the treatment of asthenozoospermia in-vivo are warranted.

EKLF-driven PIT1 expression is critical for mouse erythroid maturation in vivo and in vitro

Blood ◽  
2013 ◽  
Vol 121 (4) ◽  
pp. 666-678 ◽  
Author(s):  
Anne Forand ◽  
Laurent Beck ◽  
Christine Leroy ◽  
Alice Rousseau ◽  
Valérie Boitez ◽  
...  
Keyword(s):  
Fetal Liver ◽  
Protein A ◽  
Erythroid Cell ◽  
Functional Link ◽  
Targeted Deletion ◽  
Proliferation And Apoptosis ◽  
Erythroid Maturation

AbstractThe PIT1/SLC20A1 protein, a well-described sodium/phosphate cotransporter and retrovirus receptor, has been identified recently as a modular of proliferation and apoptosis in vitro. The targeted deletion of the PIT1 gene in mice revealed a lethal phenotype due to severe anemia attributed to defects in liver development. However, the presence of immature erythroid cells associated with impaired maturation of the globin switch led us to investigate the role of PIT1 in hematopoietic development. In the present study, specific deletion of PIT1 in the hematopoietic system and fetal liver transplantation experiments demonstrated that anemia was associated with an erythroid cell– autonomous defect. Moreover, anemia was not due to RBC destruction but rather to maturation defects. Because Erythroid Krüppel-like Factor (EKLF)–knockout mice showed similar maturation defects, we investigated the functional link between PIT1 and EKLF. We demonstrated that EKLF increases PIT1 expression during RBC maturation by binding to its promoter in vivo and that shRNA-driven depletion of either PIT1 or EKLF impairs erythroid maturation of G1E cells in vitro, whereas reexpression of PIT1 in EKLF-depleted G1E cells partially restores erythroid maturation. This is the first demonstration of a physiologic involvement of PIT1 in erythroid maturation in vivo.

scholarly journals Solution of the multistep pathway for assembly of corynanthean, strychnos, iboga, and aspidosperma monoterpenoid indole alkaloids from 19E-geissoschizine

2018 ◽  
Vol 115 (12) ◽  
pp. 3180-3185 ◽  
Author(s):  
Yang Qu ◽  
Michael E. A. M. Easson ◽  
Razvan Simionescu ◽  
Josef Hajicek ◽  
Antje M. K. Thamm ◽  
...  
Keyword(s):  
Gene Silencing ◽  
Indole Alkaloids ◽  
Enzyme Reaction ◽  
Biologically Active ◽  
Virus Induced Gene Silencing ◽  
Monoterpenoid Indole Alkaloids ◽  
Six Genes

Monoterpenoid indole alkaloids (MIAs) possess a diversity of alkaloid skeletons whose biosynthesis is poorly understood. A bioinformatic search of candidate genes, combined with their virus-induced gene silencing, targeted MIA profiling and in vitro/in vivo pathway reconstitution identified and functionally characterized six genes as well as a seventh enzyme reaction required for the conversion of 19E-geissoschizine to tabersonine and catharanthine. The involvement of pathway intermediates in the formation of four MIA skeletons is described, and the role of stemmadenine-O-acetylation in providing necessary reactive substrates for the formation of iboga and aspidosperma MIAs is described. The results enable the assembly of complex dimeric MIAs used in cancer chemotherapy and open the way to production of many other biologically active MIAs that are not easily available from nature.

scholarly journals Role of Fibronectin-Binding Proteins A and B inIn VitroCellular Infections andIn VivoSeptic Infections by Staphylococcus aureus

2011 ◽  
Vol 79 (6) ◽  
pp. 2215-2223 ◽  
Author(s):  
Hitomi Shinji ◽  
Yukio Yosizawa ◽  
Akiko Tajima ◽  
Tadayuki Iwase ◽  
Shinya Sugimoto ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Protein A ◽  
Severe Infection ◽  
Nuclear Factor Κb ◽  
Phagocytic Cells ◽  
Content Type ◽  
Fibronectin Binding

ABSTRACTFibronectin-binding protein A (FnBPA) and FnBPB are important adhesins forStaphylococcus aureusinfection. We constructedfnbAand/orfnbBmutant strains fromS. aureusSH1000, which possesses intactrsbU, and studied the role of these adhesins inin vitroandin vivoinfections. In intravenous infection, allfnbmutants caused a remarkable reduction in the colonization rate in kidneys and the mortality rate of mice.fnbBmutant caused a more severe decrease in body weight than that caused byfnbAmutant. Serum levels of interleukin-6 and nuclear factor κB (NF-κB) activation in spleen cells were remarkably reduced infnbAorfnbA fnbBmutant infections; however, there was no significant reduction infnbBmutant infections. Inin vitrocellular infection, FnBPA was shown to be indispensable for adhesion to and internalization by nonprofessional phagocytic cells upon ingestion by inflammatory macrophages and NF-κB activation. However, both FnBPs were required for efficient cellular responses. The results showed that FnBPA is more important forin vitroandin vivoinfections; however, cooperation between FnBPA and FnBPB is indispensable for the induction of severe infection resulting in septic death.

scholarly journals The emerging role of the mitochondrial-derived peptide humanin in stress resistance

2012 ◽  
Vol 50 (1) ◽  
pp. R11-R19 ◽  
Author(s):  
Kelvin Yen ◽  
Changhan Lee ◽  
Hemal Mehta ◽  
Pinchas Cohen
Keyword(s):  
Oxidative Stress ◽  
Cardiovascular Disease ◽  
Stress Resistance ◽  
Biologically Active ◽  
Serum Starvation ◽  
Endogenous Role ◽  
Biologically Active Peptide

The discovery of humanin, a novel, mitochondrial-derived peptide, has created a potentially new category of biologically active peptide. As more research unravels the endogenous role of humanin as well as its potential pharmacological use, its role in stress resistance has become clearer. Humanin protects cells from oxidative stress, serum starvation, hypoxia, and other insultsin vitroand also improves cardiovascular disease as well as Alzheimer's diseasein vivo. In this review, we discuss the emerging role of humanin in stress resistance and its proposed mechanism of action.

The Role of Polyphenols in the Modulation of Plasma Non-Enzymatic Antioxidant Capacity (NEAC)

2012 ◽  
Vol 82 (3) ◽  
pp. 228-232 ◽  
Author(s):  
Mauro Serafini ◽  
Giuseppa Morabito
Keyword(s):  
Antioxidant Capacity ◽  
Dietary Intervention ◽  
Ex Vivo ◽  
The Body ◽  
Dietary Polyphenols ◽  
Enzymatic Antioxidant ◽  
Endogenous Antioxidant

Dietary polyphenols have been shown to scavenge free radicals, modulating cellular redox transcription factors in different in vitro and ex vivo models. Dietary intervention studies have shown that consumption of plant foods modulates plasma Non-Enzymatic Antioxidant Capacity (NEAC), a biomarker of the endogenous antioxidant network, in human subjects. However, the identification of the molecules responsible for this effect are yet to be obtained and evidences of an antioxidant in vivo action of polyphenols are conflicting. There is a clear discrepancy between polyphenols (PP) concentration in body fluids and the extent of increase of plasma NEAC. The low degree of absorption and the extensive metabolism of PP within the body have raised questions about their contribution to the endogenous antioxidant network. This work will discuss the role of polyphenols from galenic preparation, food extracts, and selected dietary sources as modulators of plasma NEAC in humans.

Anti-obesity role of Aster glehni extract: in vivo and in vitro effects

Planta Medica ◽  
2012 ◽  
Vol 78 (11) ◽  
Author(s):  
HM Lee ◽  
TG Ahn ◽  
CW Kim ◽  
HJ An
Keyword(s):  
In Vitro Effects
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