Germin. Compartmentation of the protein, its translatable mRNA, and its biosynthesis among roots, stems, and leaves of wheat seedlings

1985 ◽  
Vol 63 (9) ◽  
pp. 1003-1013 ◽  
Author(s):  
Zbyszko. F. Grzelczak ◽  
Sadequr Rahman ◽  
Theresa D. Kennedy ◽  
Byron G. Lane
Keyword(s):  
Fold Increase ◽  
Wheat Seedling ◽  
Staining Technique ◽  
Seedling Development ◽  
High Mass ◽  
Fresh Weight ◽  
Wheat Seedlings ◽  
Wheat Embryo ◽  
Early Seedling

(1) Onset of growth during germination of the isolated wheat embryo is allied with the emergence of a protein we have called germin. This study was undertaken to learn if germin is present and synthesized in the root, stem, and leaf during postgerminative growth of the wheat seedling.(2) Seedlings were grown from mature wheat grains on water-soaked filter paper and organs excised at various times were pulse labeled with [35S]methionine. Germin is synthesized in all organs at all times between 1.5 and 7 days.(3) During early seedling development (1.5 days), the fraction of [35S]methionine incorporated into germin, relative to other proteins, is much greater in the case of stem than other organs, either in vivo or when cell-free protein synthesis is directed by bulk RNA from different organs.(4) During late seedling development (4–7 days), when root growth is greater than stem growth, total isotope incorporation into germin is much greater in roots than stem.(5) Quasi-quantitative estimates of germin in pepsin-treated soluble fractions of homogenates were made by visual comparison of dye binding when gels were stained by Coomassie blue. The quantity of germin (ca. 1 mg/100 g) keeps pace with growth in spite of a 100-fold increase in fresh weight during transformation of the germinating embryo into a 7-day seedling.(6) During early seedling growth (1.5 days), germin is concentrated in the stem, but later (7 days), after extensive growth of the root but not the stem, the amount of germin in the root is about 1/2 and in the leaf is about 1/10 as great as in stem, on a fresh-weight basis, but more nearly equal on a per-organ basis owing to high mass proportions of the leaf and root relative to stem.(7) The dye-staining technique following pepsin treatment of soluble proteins has been used to detect germin in the stems of other cereal (rye, barley, oat) seedlings (3–8 days).

scholarly journals O-fucosylation of CPN20 by SPINDLY Derepresses Abscisic Acid Signaling During Seed Germination and Seedling Development

2021 ◽  
Vol 12 ◽  
Author(s):  
Lin Liang ◽  
Qi Wang ◽  
Zihao Song ◽  
Yaxin Wu ◽  
Qing Liang ◽  
...  
Keyword(s):  
Seed Germination ◽  
Mammalian Cells ◽  
Electron Transfer Dissociation ◽  
Seedling Development ◽  
Aba Signaling ◽  
Early Seedling ◽  
Aba Insensitive ◽  
Early Seedling Development

SPINDLY is involved in some aspects of plant development. However, the nature of this protein as an O-fucosyltransferase was recently discovered. In this study, we show that SPINDLY (SPY) interacts with CPN20 in yeast two-hybrid and split-luc assays, and the interaction is promoted by ABA. CPN20 is a chloroplast-localized co-chaperonin that negatively regulates ABAR-mediated ABA signaling. By using Electron Transfer Dissociation-MS/MS analysis, two O-fucosylation sites, e.g., 116th and 119th threonines, were detected in ectopically expressed CPN20 in mammalian cells and in Arabidopsis. The O-fucosylation at both threonine residues was confirmed by in vitro peptide O-fucosylation assay. We further show that CPN20 accumulates in the chloroplast of spy mutants, suggesting that SPY negatively regulates CPN20 localization in the chloroplast. In vivo protein degradation assay along with CPN20 localization behavior suggest that import of CPN20 into the chloroplast is negatively regulated by SPY. Genetic analysis shows that ABA insensitive phenotypes of spy-3 in terms of seed germination and early seedling development are partially suppressed by the cpn20 mutation, suggesting that CPN20 acts downstream of SPY in this ABA signaling pathway and that there may exist other pathways in parallel with CPN20. Collectively, the above data support the notion that the O-fucosylation of CPN20 by SPY fine-tunes ABA signaling in Arabidopsis.

Distribution and Characteristics of Aminoacyl β-Naphthylamidase Activities in Wheat Seedlings

1979 ◽  
Vol 6 (6) ◽  
pp. 595 ◽  
Author(s):  
SP Waters ◽  
MJ Dalling
Keyword(s):  
Close Association ◽  
Wheat Seedling ◽  
Developmental Studies ◽  
Ph Optimum ◽  
Wheat Seedlings ◽  
Total Enzyme Activity ◽  
Crude Extracts ◽  
Imino Acids ◽  
Wheat Leaves

Gel electrophoretic studies have revealed that crude extracts from various tissues of wheat seedlings contain two major enzymes capable of hydrolysing aminoacyl �-naphthylamides. A third enzyme which exclusively hydrolyses the �-naphthylamides of the imino acids proline and hydroxyproline has also been demonstrated in wheat leaves. The pH optimum for �-naphthylamidase activity against phenylalanine �-naphthylamide in crude extracts was 7.4. The two major enzymes differ with respect to their substrate specificities; the more anionic enzyme, APl, hydrolyses a relatively narrow range of hydrophobic aminoacyl substrates including the �-naphthyIamides of leucine, phenylalanine, methionine, tyrosine and tryptophan, while the enzyme of lower electrophoretic mobility, AP2, hydrolyses a broad range of substrates. The two enzymes also differ in their sensitivity to the metal chelator 1,10-phenanthroline. The AP2 enzyme from wheat, like that from pea, appears to be a metallo-enzyme, but APl does not show any sensitivity to phenanthroline. The results of developmental studies performed with wheat seedling tissues are consistent with the view that the naphthylamidase enzymes function as aminopeptidases in vivo. A close association was observed between total enzyme activity and soluble protein content, with the highest naphthylamidase activities being found in actively growing tissues.

Plasminogen Activation In Vivo upon Intravenous Infusion of DDAVP

1992 ◽  
Vol 67 (01) ◽  
pp. 111-116 ◽  
Author(s):  
Marcel Levi ◽  
Jan Paul de Boer ◽  
Dorina Roem ◽  
Jan Wouter ten Cate ◽  
C Erik Hack
Keyword(s):  
Monoclonal Antibodies ◽  
Plasminogen Activator ◽  
Plasma Levels ◽  
Fold Increase ◽  
Fibrinolytic System ◽  
Plasminogen Activation ◽  
Plasminogen Activator Activity ◽  
Insight Into

SummaryInfusion of desamino-d-arginine vasopressin (DDAVP) results in an increase in plasma plasminogen activator activity. Whether this increase results in the generation of plasmin in vivo has never been established.A novel sensitive radioimmunoassay (RIA) for the measurement of the complex between plasmin and its main inhibitor α2 antiplasmin (PAP complex) was developed using monoclonal antibodies preferentially reacting with complexed and inactivated α2-antiplasmin and monoclonal antibodies against plasmin. The assay was validated in healthy volunteers and in patients with an activated fibrinolytic system.Infusion of DDAVP in a randomized placebo controlled crossover study resulted in all volunteers in a 6.6-fold increase in PAP complex, which was maximal between 15 and 30 min after the start of the infusion. Hereafter, plasma levels of PAP complex decreased with an apparent half-life of disappearance of about 120 min. Infusion of DDAVP did not induce generation of thrombin, as measured by plasma levels of prothrombin fragment F1+2 and thrombin-antithrombin III (TAT) complex.We conclude that the increase in plasminogen activator activity upon the infusion of DDAVP results in the in vivo generation of plasmin, in the absence of coagulation activation. Studying the DDAVP induced increase in PAP complex of patients with thromboembolic disease and a defective plasminogen activator response upon DDAVP may provide more insight into the role of the fibrinolytic system in the pathogenesis of thrombosis.

THE HISTOLOGICAL STATUS OF WHEAT EMBRYO AT THE STAGE OF ORGANOGENESIS IN VIVO AS OPTIMAL STAGE TO OBTAIN OPTIMUM MORPHOGENIC

2019 ◽  
Vol 0 (1) ◽  
pp. 25-29 ◽  
Author(s):  
N.N. Kruglova ◽  
◽  
O.A. Seldimirova ◽  
A.E. Zinatullina ◽  
◽  
...  
Keyword(s):  
Wheat Embryo

scholarly journals Zinc Seed Priming Improves Spinach Germination at Low Temperature

Agriculture ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 271
Author(s):  
Muhammad Imran ◽  
Asim Mahmood ◽  
Günter Neumann ◽  
Birte Boelt
Keyword(s):  
Low Temperature ◽  
Temperature Stress ◽  
Multispectral Imaging ◽  
Germination Rate ◽  
Cost Effective ◽  
Seed Priming ◽  
Seedling Development ◽  
Low Temperature Stress ◽  
Early Seedling ◽  
Early Seedling Development

Low temperature during germination hinders germination speed and early seedling development. Zn seed priming is a useful and cost-effective tool to improve germination rate and resistance to low temperature stress during germination and early seedling development. Spinach was tested to improve germination and seedling development with Zn seed priming under low temperature stress conditions. Zn priming increased seed Zn concentration up to 48 times. The multispectral imaging technique with VideometerLab was used as a non-destructive method to differentiate unprimed, water- and Zn-primed spinach seeds successfully. Localization of Zn in the seeds was studied using the 1,5-diphenyl thiocarbazone (DTZ) dying technique. Active translocation of primed Zn in the roots of young seedlings was detected with laser confocal microscopy. Zn priming of spinach seeds at 6 mM Zn showed a significant increase in germination rate and total germination under low temperature at 8 °C.

scholarly journals A Role for Xanthurenic Acid in the Control of Brain Dopaminergic Activity

2021 ◽  
Vol 22 (13) ◽  
pp. 6974
Author(s):  
Omar Taleb ◽  
Mohammed Maammar ◽  
Christian Klein ◽  
Michel Maitre ◽  
Ayikoe Guy Mensah-Nyagan
Keyword(s):  
Dopamine Release ◽  
Intraperitoneal Administration ◽  
Glutamate Transporter ◽  
Fold Increase ◽  
Xanthurenic Acid ◽  
Metabotropic Receptors ◽  
Parent Molecule ◽  
Dopaminergic Activity ◽  
The Brain

Xanthurenic acid (XA) is a metabolite of the kynurenine pathway (KP) synthetized in the brain from dietary or microbial tryptophan that crosses the blood-brain barrier through carrier-mediated transport. XA and kynurenic acid (KYNA) are two structurally related compounds of KP occurring at micromolar concentrations in the CNS and suspected to modulate some pathophysiological mechanisms of neuropsychiatric and/or neurodegenerative diseases. Particularly, various data including XA cerebral distribution (from 1 µM in olfactory bulbs and cerebellum to 0.1–0.4 µM in A9 and A10), its release, and interactions with G protein-dependent XA-receptor, glutamate transporter and metabotropic receptors, strongly support a signaling and/or neuromodulatory role for XA. However, while the parent molecule KYNA is considered as potentially involved in neuropsychiatric disorders because of its inhibitory action on dopamine release in the striatum, the effect of XA on brain dopaminergic activity remains unknown. Here, we demonstrate that acute local/microdialysis-infusions of XA dose-dependently stimulate dopamine release in the rat prefrontal cortex (four-fold increase in the presence of 20 µM XA). This stimulatory effect is blocked by XA-receptor antagonist NCS-486. Interestingly, our results show that the peripheral/intraperitoneal administration of XA, which has been proven to enhance intra-cerebral XA concentrations (about 200% increase after 50 mg/kg XA i.p), also induces a dose-dependent increase of dopamine release in the cortex and striatum. Furthermore, our in vivo electrophysiological studies reveal that the repeated/daily administrations of XA reduce by 43% the number of spontaneously firing dopaminergic neurons in the ventral tegmental area. In the substantia nigra, XA treatment does not change the number of firing neurons. Altogether, our results suggest that XA may contribute together with KYNA to generate a KYNA/XA ratio that may crucially determine the brain normal dopaminergic activity. Imbalance of this ratio may result in dopaminergic dysfunctions related to several brain disorders, including psychotic diseases and drug dependence.

scholarly journals Effect of Time and Legume Type on Germination-Induced Proteolysis of Lentils and Faba Beans

Proceedings ◽  
2020 ◽  
Vol 70 (1) ◽  
pp. 4
Author(s):  
Sara Bautista-Expósito ◽  
Elena Peñas ◽  
Albert Vanderberg ◽  
Juana Frias ◽  
Cristina Martínez-Villaluenga
Keyword(s):  
Amino Acids ◽  
Protease Activity ◽  
Protein Quality ◽  
Principal Component ◽  
Fold Increase ◽  
Protein Digestibility ◽  
Essential Amino Acids ◽  
Seedling Development ◽  
Positive Effects ◽  
Faba Beans

Legumes are alternative protein sources that have been successfully used to develop diverse meatless foods. Although these plant-based products have a lower impact on the environment than equivalent animal-based products, they have lower protein digestibility. Germination could be a useful bioprocess to enhance protein digestibility in legumes, although its effect at different times of seedling development has been little studied in lentils and faba beans. This work investigated the effect of germination time (4 and 6 days after full seed imbibition) on the proteins of three types of Canadian lentils (“gray zero tannin”, G; “caviar black”, B; and “red dehulled”, D) and faba beans (“zero vicin/convicin”, F). Germination increased total nitrogen (4–14% increase) and total levels of some amino acids: Asp in all the sprouts studied; Ser, Pro, Ala, Cys, His and Lys in G; and Met and Tyr in B. A concurrent degradation of the 7S and 11S globulin subunits, the accumulation of peptides below 20 kDa and free essential and non-essential amino acids (4- to 6-fold increase) were observed after germination in all the legumes studied. These effects were attributable to the increased protease activity observed after sprouting. Trypsin inhibitory activity was lower in legume sprouts, except for D, where a small increase was detected. Time, legume type and their interaction showed significant effects on the parameters studied. Germination effects were generally more remarkable at longer stages of seedling development. Among the legumes studied, D showed a differential behavior characterized by a faster protein degradation and release of small peptides, probably due to its higher protease activity as indicated by principal component analysis. These results evidence the positive effects of germination on the protein digestibility of different lentil types and faba beans. The protein quality of plant-based foods could be improved through the selection of legume species with higher germination-induced proteolytic rates and optimized germination times.

scholarly journals Methylation of rRNA as a host defense against rampant group II intron retrotransposition

Mobile DNA ◽  
2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Justin M. Waldern ◽  
Dorie Smith ◽  
Carol Lyn Piazza ◽  
E. Jake Bailey ◽  
Nicholas J. Schiraldi ◽  
...  
Keyword(s):  
Insertional Mutagenesis ◽  
Fold Increase ◽  
Group Ii Intron ◽  
In Vivo Experiments ◽  
Cellular Factors ◽  
Group Ii ◽  
Self Splicing ◽  
Native Host

Abstract Background Group II introns are mobile retroelements, capable of invading new sites in DNA. They are self-splicing ribozymes that complex with an intron-encoded protein to form a ribonucleoprotein that targets DNA after splicing. These molecules can invade DNA site-specifically, through a process known as retrohoming, or can invade ectopic sites through retrotransposition. Retrotransposition, in particular, can be strongly influenced by both environmental and cellular factors. Results To investigate host factors that influence retrotransposition, we performed random insertional mutagenesis using the ISS1 transposon to generate a library of over 1000 mutants in Lactococcus lactis, the native host of the Ll.LtrB group II intron. By screening this library, we identified 92 mutants with increased retrotransposition frequencies (RTP-ups). We found that mutations in amino acid transport and metabolism tended to have increased retrotransposition frequencies. We further explored a subset of these RTP-up mutants, the most striking of which is a mutant in the ribosomal RNA methyltransferase rlmH, which exhibited a reproducible 20-fold increase in retrotransposition frequency. In vitro and in vivo experiments revealed that ribosomes in the rlmH mutant were defective in the m3Ψ modification and exhibited reduced binding to the intron RNA. Conclusions Taken together, our results reinforce the importance of the native host organism in regulating group II intron retrotransposition. In particular, the evidence from the rlmH mutant suggests a role for ribosome modification in limiting rampant retrotransposition.

scholarly journals Neuron-specific activation of necroptosis signaling in multiple sclerosis cortical grey matter

2021 ◽  
Vol 141 (4) ◽  
pp. 585-604 ◽  
Author(s):  
Carmen Picon ◽  
Anusha Jayaraman ◽  
Rachel James ◽  
Catriona Beck ◽  
Patricia Gallego ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
Signaling Pathway ◽  
Cortical Neurons ◽  
Grey Matter ◽  
Molecular Mechanisms ◽  
Fold Increase ◽  
Cell Types ◽  
Meningeal Inflammation ◽  
Cortical Grey Matter

AbstractSustained exposure to pro-inflammatory cytokines in the leptomeninges is thought to play a major role in the pathogenetic mechanisms leading to cortical pathology in multiple sclerosis (MS). Although the molecular mechanisms underlying neurodegeneration in the grey matter remain unclear, several lines of evidence suggest a prominent role for tumour necrosis factor (TNF). Using cortical grey matter tissue blocks from post-mortem brains from 28 secondary progressive MS subjects and ten non-neurological controls, we describe an increase in expression of multiple steps in the TNF/TNF receptor 1 signaling pathway leading to necroptosis, including the key proteins TNFR1, FADD, RIPK1, RIPK3 and MLKL. Activation of this pathway was indicated by the phosphorylation of RIPK3 and MLKL and the formation of protein oligomers characteristic of necrosomes. In contrast, caspase-8 dependent apoptotic signaling was decreased. Upregulation of necroptotic signaling occurred predominantly in macroneurons in cortical layers II–III, with little expression in other cell types. The presence of activated necroptotic proteins in neurons was increased in MS cases with prominent meningeal inflammation, with a 30-fold increase in phosphoMLKL+ neurons in layers I–III. The density of phosphoMLKL+ neurons correlated inversely with age at death, age at progression and disease duration. In vivo induction of chronically elevated TNF and INFγ levels in the CSF in a rat model via lentiviral transduction in the meninges, triggered inflammation and neurodegeneration in the underlying cortical grey matter that was associated with increased neuronal expression of TNFR1 and activated necroptotic signaling proteins. Exposure of cultured primary rat cortical neurons to TNF induced necroptosis when apoptosis was inhibited. Our data suggest that neurons in the MS cortex are dying via TNF/TNFR1 stimulated necroptosis rather than apoptosis, possibly initiated in part by chronic meningeal inflammation. Neuronal necroptosis represents a pathogenetic mechanism that is amenable to therapeutic intervention at several points in the signaling pathway.

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