Search results for "Phosphorylation"
showing 10 items of 975 documents
Post-translational Modifications in Plant Nuclear Signaling: Novel Insights Into Responses to Environmental Changes
2019
Just imagine a Plant Science professor in front of a classroom full of interested and attentive students. Imagine what their answers to this intriguing question would be: “What are, according to you, the functions ensured by the plant cell nucleus?” It would be very surprising if some of them would answer cell signaling in response to biotic and abiotic stresses or developmental processes. Most of them would probably answer according to a classical point of view: DNA replication or gene expression. Hence it is still admitted in recent publications (see for instance Fedorenko et al., 2010) that molecules smaller than 40 kDa can diffuse freely across the nuclear envelope pores. However, Pauly…
Rapid changes in heat-shock cognate 70 levels, heat-shock cognate phosphorylation state, heat-shock transcription factor, and metal transcription fac…
2010
The aim of the present study was to analyze and compare the effects of several metals on the embryos of the sea urchin Paracentrotus lividus, a key species within the Mediterranean Sea ecosystem. Embryos were continuously exposed from fertilization to the following metals: 0.6 mg/l copper, 3 mg/l lead, and 6 mg/l nickel. The embryos were then monitored for metal responses at the gastrula stage, which occurred 24 h after exposure. A biochemical multi-experimental approach was taken and involved the investigation of the levels of HSC70 expression and the involvement of heat shock factor (HSF) and/or metal transcription factor (MTF) in the response. Immunoblotting assays and electrophoretic mo…
Sea urchin deciliation induces thermoresistance and activates the p38 mitogen-activated protein kinase pathway.
2003
In this study, we demonstrate by a variety of approaches (ie, morphological analysis, Western blots, immunolocalization, and the use of specific antibodies) that hyperosmotic deciliation stress of sea urchin embryos induces a thermotolerant response. Deciliation is also able to activate a phosphorylation signaling cascade the effector of which might be the p38 stress-activated protein kinase because we found that the administration of the p38 inhibitor SB203580 to sea urchin deciliated gastrula embryos makes the hyperosmotic deciliation stress lethal.
Achievement of thermotolerance through hsps phosphorylation in sea urchin embryos.
1995
TPA treatment of sea urchin embryos is able to induce thermotolerance. Evidence is provided that TPA treatment induces phosphorylation of a constitutive stress protein of 38 KDa.
Casein kinase 2 inhibits HomolD-directed transcription by Rrn7 in Schizosaccharomyces pombe.
2014
In Schizosaccharomyces pombe, ribosomal protein gene (RPG) promoters contain a TATA analogue element called the HomolD box. The HomolD-binding protein Rrn7 forms a complex with the RNA polymerase II machinery. Despite the importance of ribosome biogenesis to cell survival, the mechanisms involved in the regulation of transcription of eukaryotic RPGs are unknown. In this study, we identified Rrn7 as a new substrate of the pleiotropic casein kinase 2 (CK2), which is a regulator of basal transcription. Recombinant Rrn7 from S. pombe, which is often used as a model organism for studying eukaryotic transcription, interacted with CK2 in vitro and in vivo. Furthermore, CK2-mediated phosphorylation…
Sigma-1 Receptor Activation Induces Autophagy and Increases Proteostasis Capacity In Vitro and In Vivo
2019
Dysfunction of autophagy and disturbed protein homeostasis are linked to the pathogenesis of human neurodegenerative diseases and the modulation of autophagy as the protein clearance process has become one key pharmacological target. Due to the role of sigma-1 receptors (Sig-1R) in learning and memory, and the described pleiotropic neuroprotective effects in various experimental paradigms, Sig-1R activation is recognized as one potential approach for prevention and therapy of neurodegeneration and, interestingly, in amyotrophic lateral sclerosis associated with mutated Sig-1R, autophagy is disturbed. Here we analyzed the effects of tetrahydro-N,N-dimethyl-2,2-diphenyl-3-furanmethanamine hyd…
A (1->3)-beta-D-glucan recognition protein from the sponge Suberites domuncula. Mediated activation of fibrinogen-like protein and epidermal growth f…
2004
Sponges (phylum Porifera) live in a symbiotic relationship with microorganisms, primarily bacteria. Until now, molecular proof for the capacity of sponges to recognize fungi in the surrounding aqueous milieu has not been available. Here we demonstrate, for the demosponge Suberites domuncula (Porifera, Demospongiae, Hadromerida), a cell surface receptor that recognizes (1--3)-beta-D-glucans, e.g. curdlan or laminarin. This receptor, the (1--3)-beta-D-glucan-binding protein, was identified and its cDNA analysed. The gene coding for the 45 kDa protein was found to be upregulated in tissue after incubation with carbohydrate. Simultaneously with the increased expression of this gene, two further…
The catalytic mechanism of glyceraldehyde 3-phosphate dehydrogenase from Trypanosoma cruzi elucidated via the QM/MM approach
2013
Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) has been identified as a key enzyme involved in glycolysis processes for energy production in the Trypanosoma cruzi parasite. This enzyme catalyses the oxidative phosphorylation of glyceraldehyde 3-phosphate (G3P) in the presence of inorganic phosphate (Pi) and nicotinamide adenosine dinucleotide (NAD+). The catalytic mechanism used by GAPDH has been intensively investigated. However, the individual roles of Pi and the C3 phosphate of G3P (Ps) sites, as well as some residues such as His194 in the catalytic mechanism, remain unclear. In this study, we have employed Molecular Dynamics (MD) simulations within hybrid quantum mechanical/molecular …
Role of Reduced Lipoic Acid in the Redox Regulation of Mitochondrial Aldehyde Dehydrogenase (ALDH-2) Activity
2007
Chronic therapy with nitroglycerin results in a rapid development of nitrate tolerance, which is associated with an increased production of reactive oxygen species. We have recently shown that mitochondria are an important source of nitroglycerin-induced oxidants and that the nitroglycerin-bioactivating mitochondrial aldehyde dehydrogenase is oxidatively inactivated in the setting of tolerance. Here we investigated the effect of various oxidants on aldehyde dehydrogenase activity and its restoration by dihydrolipoic acid. In vivo tolerance in Wistar rats was induced by infusion of nitroglycerin (6.6 microg/kg/min, 4 days). Vascular reactivity was measured by isometric tension studies of iso…
Unjamming overcomes kinetic and proliferation arrest in terminally differentiated cells and promotes collective motility of carcinoma
2018
Under homeostatic conditions, mature epithelia are locked in a kinetically-silent, jammed state. During wound repair or branching morphogenesis epithelia must unjam and acquire liquid-like properties. These events might be recapitulated in the transition from in situ to invasive cancer stages. How cells control this transition and how biologically relevant it is, however, remains unclear. Recently, we showed that altering RAB5A levels, a master regulator of endosomal trafficking, is sufficient to re-awaken motility in jammed epithelia, through ill-defined, endocytic-sensitive biochemical pathways. Here, we show that RAB5A promotes non-clathrin-dependent internalization of epidermal growth f…