scholarly journals Tissue-autonomous phenylpropanoid production is essential for establishment of root barriers

2020 ◽  
Author(s):  
Tonni Grube Andersen ◽  
David Molina ◽  
Joachim Kilian ◽  
Rochus Franke ◽  
Laura Ragni ◽  
...  

ABSTRACTPlants deposit polymeric barriers in their root cell walls to protect against external stress and facilitate selective nutrient uptake. The compounds that make up these barriers originate from the fatty acid- and phenylpropanoid biosynthetic pathways. Although the machinery responsible for production of the barrier constituents is well-char-acterized, our pathway models lack spatiotemporal resolution – especially in roots - and the source tissue is often not clear due to the apoplastic nature of barriers. Insights into how the individual root tissues or cells contribute to forming apoplastic barriers is important for elucidation of their ultrastructure, function and development. Manipulation of the associated biosynthesis is delicate, as mutants often display pleiotropic phenotypes due to the broad role of the underlying metabolites. Here, we address these issues by creating a genetic tool that allows in vivo repression of the phenylpropanoid pathway with both spatial and temporal control. We provide strong evidence that tissue-auton-omous production of phenylpropanoids is essential for establishment of the endodermal Casparian strip. Moreover, we find that in order to maintain deposition and attachment of a coherent suberin matrix to the cell wall, cells require continuous production of aromatic constituents. This process is especially crucial in the suberized endodermis where we find that repression of phenylpropanoid production leads to active removal of suberin.

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Jiang Lan Fan ◽  
Jose A. Rivera ◽  
Wei Sun ◽  
John Peterson ◽  
Henry Haeberle ◽  
...  

AbstractUnderstanding the structure and function of vasculature in the brain requires us to monitor distributed hemodynamics at high spatial and temporal resolution in three-dimensional (3D) volumes in vivo. Currently, a volumetric vasculature imaging method with sub-capillary spatial resolution and blood flow-resolving speed is lacking. Here, using two-photon laser scanning microscopy (TPLSM) with an axially extended Bessel focus, we capture volumetric hemodynamics in the awake mouse brain at a spatiotemporal resolution sufficient for measuring capillary size and blood flow. With Bessel TPLSM, the fluorescence signal of a vessel becomes proportional to its size, which enables convenient intensity-based analysis of vessel dilation and constriction dynamics in large volumes. We observe entrainment of vasodilation and vasoconstriction with pupil diameter and measure 3D blood flow at 99 volumes/second. Demonstrating high-throughput monitoring of hemodynamics in the awake brain, we expect Bessel TPLSM to make broad impacts on neurovasculature research.


Molecules ◽  
2021 ◽  
Vol 26 (14) ◽  
pp. 4221
Author(s):  
Aage Kristian Olsen Alstrup ◽  
Svend Borup Jensen ◽  
Ole Lerberg Nielsen ◽  
Lars Jødal ◽  
Pia Afzelius

The development of new and better radioactive tracers capable of detecting and characterizing osteomyelitis is an ongoing process, mainly because available tracers lack selectivity towards osteomyelitis. An integrated part of developing new tracers is the performance of in vivo tests using appropriate animal models. The available animal models for osteomyelitis are also far from ideal. Therefore, developing improved animal osteomyelitis models is as important as developing new radioactive tracers. We recently published a review on radioactive tracers. In this review, we only present and discuss osteomyelitis models. Three ethical aspects (3R) are essential when exposing experimental animals to infections. Thus, we should perform experiments in vitro rather than in vivo (Replacement), use as few animals as possible (Reduction), and impose as little pain on the animal as possible (Refinement). The gain for humans should by far exceed the disadvantages for the individual experimental animal. To this end, the translational value of animal experiments is crucial. We therefore need a robust and well-characterized animal model to evaluate new osteomyelitis tracers to be sure that unpredicted variation in the animal model does not lead to a misinterpretation of the tracer behavior. In this review, we focus on how the development of radioactive tracers relies heavily on the selection of a reliable animal model, and we base the discussions on our own experience with a porcine model.


2021 ◽  
Vol 9 (2) ◽  
pp. 206
Author(s):  
Martyna Cieślik ◽  
Natalia Bagińska ◽  
Andrzej Górski ◽  
Ewa Jończyk-Matysiak

The authors emphasize how extremely important it is to highlight the role played by animal models in an attempt to determine possible phage interactions with the organism into which it was introduced as well as to determine the safety and effectiveness of phage therapy in vivo taking into account the individual conditions of a given organism and its physiology. Animal models in which phages are used make it possible, among other things, to evaluate the effective therapeutic dose and to choose the possible route of phage administration depending on the type of infection developed. These results cannot be applied in detail to the human body, but the knowledge gained from animal experiments is invaluable and very helpful. We would like to highlight how useful animal models may be for the possible effectiveness evaluation of phage therapy in the case of infections caused by gram-negative bacteria from the ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacter species) group of pathogens. In this review, we focus specifically on the data from the last few years.


Nanomaterials ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 547
Author(s):  
Marina Ramal-Sanchez ◽  
Antonella Fontana ◽  
Luca Valbonetti ◽  
Alessandra Ordinelli ◽  
Nicola Bernabò ◽  
...  

Since its discovery, graphene and its multiple derivatives have been extensively used in many fields and with different applications, even in biomedicine. Numerous efforts have been made to elucidate the potential toxicity derived from their use, giving rise to an adequate number of publications with varied results. On this basis, the study of the reproductive function constitutes a good tool to evaluate not only the toxic effects derived from the use of these materials directly on the individual, but also the potential toxicity passed on to the offspring. By providing a detailed scientometric analysis, the present review provides an updated overview gathering all the research studies focused on the use of graphene and graphene-based materials in the reproductive field, highlighting the consequences and effects reported to date from experiments performed in vivo and in vitro and in different animal species (from Archea to mammals). Special attention is given to the oxidized form of graphene, graphene oxide, which has been recently investigated for its ability to increase the in vitro fertilization outcomes. Thus, the potential use of graphene oxide against infertility is hypothesized here, probably by engineering the spermatozoa and thus manipulating them in a safer and more efficient way.


2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Vittorino Lanzio ◽  
Gregory Telian ◽  
Alexander Koshelev ◽  
Paolo Micheletti ◽  
Gianni Presti ◽  
...  

AbstractThe combination of electrophysiology and optogenetics enables the exploration of how the brain operates down to a single neuron and its network activity. Neural probes are in vivo invasive devices that integrate sensors and stimulation sites to record and manipulate neuronal activity with high spatiotemporal resolution. State-of-the-art probes are limited by tradeoffs involving their lateral dimension, number of sensors, and ability to access independent stimulation sites. Here, we realize a highly scalable probe that features three-dimensional integration of small-footprint arrays of sensors and nanophotonic circuits to scale the density of sensors per cross-section by one order of magnitude with respect to state-of-the-art devices. For the first time, we overcome the spatial limit of the nanophotonic circuit by coupling only one waveguide to numerous optical ring resonators as passive nanophotonic switches. With this strategy, we achieve accurate on-demand light localization while avoiding spatially demanding bundles of waveguides and demonstrate the feasibility with a proof-of-concept device and its scalability towards high-resolution and low-damage neural optoelectrodes.


Author(s):  
Thriveni Vasanth Kumar ◽  
Manjunatha H. ◽  
Rajesh Kp

Objective: Dietary curcumin and capsaicin are well known for their health beneficial potencies. The current study was done to assess the anti-inflammatory activity of curcumin, capsaicin and their combination by employing in vitro and in vivo models.Methods: We investigated the protective effect of curcumin, capsaicin and their combination using in vitro heat induced human red blood cell (HRBC) membrane stabilisation, in vivo 3% agar induced leukocyte mobilisation and acetic acid induced vascular permeability assay.Results: Curcumin, capsaicin and their combination exhibited concentration dependent protective effect against heat-induced HRBC membrane destabilisation, while combined curcumin and capsaicin restored 87.0±0.64 % membrane stability and it is found to be better than curcumin, capsaicin and diclofenac sodium (75.0±0.25. 72±0.9 and 80.0±0.31 %) protective effect. In agar suspension induced leukocyte mobilization assay, the combined curcumin and capsaicin had shown 39.5±1.58 % of inhibition compared to individual curcumin and capsaicin, which showed moderate inhibition of 16.0±3.14 and 21.6±2.17 % respectively. Besides, the combined curcumin and capsaicin had shown highly significant inhibition of acetic acid-induced vascular permeability in rats (62.0±3.14 %), whereas individual curcumin and capsaicin showed moderate inhibition of vascular permeability with 36.0±2.41 and 43.0±1.92 % respectively.Conclusion: This study demonstrates the significant anti-inflammatory property of combined curcumin and capsaicin at half of the individual concentration of curcumin and capsaicin.


Antioxidants ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 463
Author(s):  
Gabriela Krausova ◽  
Antonin Kana ◽  
Marek Vecka ◽  
Ivana Hyrslova ◽  
Barbora Stankova ◽  
...  

The selenium (Se) enrichment of yeasts and lactic acid bacteria (LAB) has recently emerged as a novel concept; the individual health effects of these beneficial microorganisms are combined by supplying the essential micronutrient Se in a more bioavailable and less toxic form. This study investigated the bioavailability of Se in the strains Enterococcus faecium CCDM 922A (EF) and Streptococcus thermophilus CCDM 144 (ST) and their respective Se-enriched forms, SeEF and SeST, in a CD (SD-Sprague Dawley) IGS rat model. Se-enriched LAB administration resulted in higher Se concentrations in the liver and kidneys of rats, where selenocystine was the prevalent Se species. The administration of both Se-enriched strains improved the antioxidant status of the animals. The effect of the diet was more pronounced in the heart tissue, where a lower glutathione reductase content was observed, irrespective of the Se fortification in LAB. Interestingly, rats fed diets with EF and SeEF had higher glutathione reductase activity. Reduced concentrations of serum malondialdehyde were noted following Se supplementation. Diets containing Se-enriched strains showed no macroscopic effects on the liver, kidneys, heart, and brain and had no apparent influence on the basic parameters of the lipid metabolism. Both the strains tested herein showed potential for further applications as promising sources of organically bound Se and Se nanoparticles.


RNA ◽  
2022 ◽  
pp. rna.078814.121
Author(s):  
Anna Ender ◽  
Nadine Grafl ◽  
Tim Kolberg ◽  
Sven Findeiss ◽  
Peter F. Stadler ◽  
...  

Removal of the 5' leader region is an essential step in the maturation of tRNA molecules in all domains of life. This reaction is catalyzed by various RNase P activities, ranging from ribonucleoproteins with ribozyme activity to protein-only forms. In Escherichia coli, the efficiency of RNase P mediated cleavage can be controlled by computationally designed riboswitch elements in a ligand-dependent way, where the 5' leader sequence of a tRNA precursor is either sequestered in a hairpin structure or presented as a single-stranded region accessible for maturation. In the presented work, the regulatory potential of such artificial constructs is tested on different forms of eukaryotic RNase P enzymes – two protein-only RNase P enzymes (PRORP1 and PRORP2) from Arabidopsis thaliana and the ribonucleoprotein of Homo sapiens. The PRORP enzymes were analyzed in vitro as well as in vivo in a bacterial RNase P complementation system. We also tested in HEK293T cells whether the riboswitches remain functional with human nuclear RNase P. While the regulatory principle of the synthetic riboswitches applies for all tested RNase P enzymes, the results also show differences in the substrate requirements of the individual enzyme versions. Hence, such designed RNase P riboswitches represent a novel tool to investigate the impact of the structural composition of the 5'-leader on substrate recognition by different types of RNase P enzymes.


1995 ◽  
Vol 79 (1) ◽  
pp. 331-339 ◽  
Author(s):  
B. Grassi ◽  
G. Ferretti ◽  
B. Kayser ◽  
M. Marzorati ◽  
A. Colombini ◽  
...  

The lower peak lactate accumulation in blood ([La(b)]p) at altitude may be associated with a reduced maximal glycolytic flux. Based on certain assumptions, the latter can be indirectly evaluated in vivo, during short supramaximal exercises, by measuring the maximal rate of lactate accumulation in blood (delta [La(b)]max). delta [La(b)]max was determined on six white subjects at sea level (SL1), after approximately 1 wk (Alt1) and 4 wk (Alt2) of a 35-day sojourn at 5,050 m, and 1 wk after return to sea level (SL2). The subjects performed exercises of increasing duration (5, 15, 25, 35, 45 s or until exhaustion) on a bicycle ergometer at loads = 200% of the individual Wmax. The latter was previously determined in each condition as the greatest work rate that could be sustained for 2–4 min during an incremental exercise. Net [La(b)] accumulation (delta [La(b)]) was measured after each exercise bout. delta [La(b)] resulted to be linearly related to exercise duration. The slopes of the individual delta [La(b)] vs. exercise duration lines were taken as delta [La(b)]max. Exhaustion times were approximately 30–45 s in all conditions. [La(b)]p (in mM) during recovery after the exhaustive load was higher at SL1 (10.22 +/- 1.09; means +/- SD) than at Alt1 (5.08 +/- 0.82), Alt2 (8.13 +/- 2.67), and SL2 (8.18 +/- 1.43). delta [La(b)]max was lower at Alt1 (0.09 +/- 0.02) and at Alt2 (0.17 +/- 0.05) than at SL1 (0.25 +/- 0.05) and SL2 (0.23 +/- 0.06). Both [La(b)]p and delta [La(b)]max increased during acclimatization.


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