Search results for "Biosynthesis"

Dexamethasone modulates α2-macroglobulin and apolipoprotein E gene expression in cultured rat liver fat-storing (Ito) cells

1991

Fat-storing (Ito) cells are perisinusoidal liver cells thought to play a central role in vitamin A metabolism and fibrogenesis. Glucocorticoids have been shown to be beneficial in the treatment of certain types of liver diseases by delaying the development of cirrhosis. To study the regulatory effects of dexamethasone on Ito cell gene expression, Ito cells were isolated from normal rat liver and primary cultures were established. The effect of dexamethasone on the synthesis of α2-macroglobulin, apolipoprotein E, fibronectin and actin was examined. Protein synthesis was studied both at the protein level and at the RNA level by means of biosynthetic labeling, immunoprecipitation followed by s…

Effect of rat plasma high density lipoprotein with or without apolipoprotein E on the cholesterol uptake and on the induction of the corticosteroid b…

1991

Abstract High density lipoprotein (HDL) has been shown to induce the cellular accumulation of cholesterol esters and the biosynthesis of 21-hydroxysteroids (corticosteroids) newborn rat adrenocortical cells cultivated in serum-free medium. In order to identify the component(s) of HDL responsible for these effects, we investigated the ability of rat HDL subfractions and HDL with or without apolipoprotein E to deliver cholesterol to cells and to stimulate the steroid biosynthetic pathways in adrenal cultured cells. The total cholesterol uptake from HDL 2 was greater than that observed with HDL rich in apolipoprotein E (HDL 1 and HDL c ). Furthermore, the increase of the ratio between 21-hydro…

Temporal aspects of copper homeostasis and its crosstalk with hormones

2015

To cope with the dual nature of copper as being essential and toxic for cells, plants temporarily adapt the expression of copper homeostasis components to assure its delivery to cuproproteins while avoiding the interference of potential oxidative damage derived from both copper uptake and photosynthetic reactions during light hours. The circadian clock participates in the temporal organization of coordination of plant nutrition adapting metabolic responses to the daily oscillations. This timely control improves plant fitness and reproduction and holds biotechnological potential to drive increased crop yields. Hormonal pathways, including those of abscisic acid, gibberellins, ethylene, auxin…

Study of oligogalacturonides-triggered Nitric Oxide (NO) production provokes new questioning about the origin of NO biosynthesis in plants

2014

Addendum to: Rasul S, Dubreuil-Maurizi C, Lamotte O, Koen E, Poinssot B, Alcaraz G, et al. Nitric oxide production mediates oligogalacturonide-triggered immunity and resistance to Botrytis cinerea in Arabidopsis thaliana. Plant Cell Environ 2012; PMID:22394204; http://dx.doi. org/10.1111/j.1365-3040.2012.02505.x.; International audience; We investigated the production and function of nitric oxide (NO) in Arabidopsis thaliana leaf discs as well as whole plants elicited by oligogalacturonides (OGs). Using genetic, biochemical and pharmacological approaches, we provided evidence that OGs induced a Nitrate Reductase (NR)-dependent NO production together with an increased NR activity and NR tran…

The influence of smoke volatiles on sexual maturation and juvenile hormone biosynthesis in the black army cutworm, Actebia fennica (Lepidoptera: Noct…

2000

0965-1748 (Print) Journal Article Research Support, Non-U.S. Gov't; Outbreaks of the black army cutworm, Actebia fennica, are associated with recently burned sites, where larvae feed on early successional plants. In the present paper we show that smoke volatiles stimulate juvenile hormone biosynthesis in virgin females, resulting in a more rapid rate of oocyte maturation and a significant advance in the age of first calling (the release of the sex pheromone) compared to control females. The ecological implications of this physiological effect are discussed.

An active form of sphingosine kinase-1 is released in the extracellular medium as component of membrane vesicles shed by two human tumor cell line.

2010

Expression of sphingosine kinase-1 (SphK-1) correlates with a poor survival rate of tumor patients. This effect is probably due to the ability of SphK-1 to be released into the extracellular medium where it catalyzes the biosynthesis of sphingosine-1-phosphate (S1P), a signaling molecule endowed with profound proangiogenic effects. SphK-1 is a leaderless protein which is secreted by an unconventional mechanism. In this paper, we will show that in human hepatocarcinoma Sk-Hep1 cells, extracellular signaling is followed by targeting the enzyme to the cell surface and parallels targeting of FGF-2 to the budding vesicles. We will also show that SphK-1 is present in a catalitycally active form i…

A bi-allelic loss-of-function SARS1 variant in children with neurodevelopmental delay, deafness, cardiomyopathy, and decompensation during fever

2021

Aminoacyl-tRNA synthetases (aaRS) are ubiquitously expressed enzymes responsible for ligating amino acids to their cognate tRNA molecules through an aminoacylation reaction. The resulting aminoacyl-tRNA is delivered to ribosome elongation factors to participate in protein synthesis. Seryl-tRNA synthetase (SARS1) is one of the cytosolic aaRSs and catalyzes serine attachment to tRNASer . SARS1 deficiency has already been associated with moderate intellectual disability, ataxia, muscle weakness, and seizure in one family. We describe here a new clinical presentation including developmental delay, central deafness, cardiomyopathy, and metabolic decompensation during fever leading to death, in a…

The structure and biosynthesis of heinamides A1-A3 and B1-B5, antifungal members of the laxaphycin lipopeptide family.

2021

Laxaphycins are a family of cyclic lipopeptides with synergistic antifungal and antiproliferative activities. They are produced by multiple cyanobacterial genera and comprise two sets of structurally unrelated 11- and 12-residue macrocyclic lipopeptides. Here, we report the discovery of new antifungal laxaphycins from Nostoc sp. UHCC 0702, which we name heinamides, through antimicrobial bioactivity screening. We characterized the chemical structures of eight heinamide structural variants A1-A3 and B1-B5. These variants contain the rare non-proteinogenic amino acids 3-hydroxy-4-methylproline, 4-hydroxyproline, 3-hydroxy-d-leucine, dehydrobutyrine, 5-hydroxyl beta-amino octanoic acid, and O-c…

ChemInform Abstract: Combinatorial Biosynthesis of Polyketides

2010

Biotechnology of Rhodococcus for the production of valuable compounds

2020

Abstract Bacteria belonging to Rhodococcus genus represent ideal candidates for microbial biotechnology applications because of their metabolic versatility, ability to degrade a wide range of organic compounds, and resistance to various stress conditions, such as metal toxicity, desiccation, and high concentration of organic solvents. Rhodococcus spp. strains have also peculiar biosynthetic activities that contribute to their strong persistence in harsh and contaminated environments and provide them a competitive advantage over other microorganisms. This review is focused on the metabolic features of Rhodococcus genus and their potential use in biotechnology strategies for the production o…