Proteins synthesis inhibition

Translation of the viral genome is required to bring about the inhibition of cellular protein synthesis. If the poliovirus genome is inactivated by ultraviolet irradiation prior to the infection of cells, no inhibition of cellular protein synthesis can be observed (11, 12), The OT treatment results in, among other alterations, the formation of uridine dimers in the ENA, thus blocking its translation, but presumably has little effect on the input viral capsid proteins. If cells are infected in the presence of cycloheximide (ll) or puron rcin, upon removal of the drugs, protein synthesis resumes at the control levels of uninfected cells for a 

Involvement of a viral structural protein in shut-off. A structural protein may be involved in the shut-off of cellular protein synthesis. This conclusion was derived from experiments by Steiner-Pryor and Cooper (14) who observed that certain temperature sensitive mutants of poliovirus defective in the structmal proteins of the virus particle were mable to inhibit cellular protein synthesis at the non-permissive temperature. 

Mutants defective in non-structural proteins, including some involved in ENA replication, displayed the normal shut-off phenotype, suggesting that ENA replication is not necessary for shut-off. 

Similar conclusions were derived from studies with inhibitors of viral ENA synthesis (15)  

The rate of cellular ENA synthesis also declines soon after infection of cells with a picornavimis. In mengovirus infected L-cells, ENA synthesis is inhibited rapidly to less than 10 of 

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Other, more general effects of insulin on cellular function include stimulation of cell growth (increase in DNA and protein synthesis), inhibition of apoptosis, and modulation of ion-channel activity. 

Clarke, H. J., and Masui, Y. (1983). The induction of reversible and irreversible chromosome decondensation by protein synthesis inhibition during meiotic maturation of mouse oocytes. Dev. Biol. 97 291-301. 

Azcona-Olivera, J. I. et al. Induction of cytokine mRNAs in mice after oral exposure to the trichothecene vomitoxin (deoxynivalenol) Relationship to toxin distribution and protein synthesis inhibition. Toxicol. Appl. Pharmacol. 133, 109, 1995. 

Froscio SM, Humpage AR, Burcham PC, Falconer IR (2003) Cylindrospermopsin-induced protein synthesis inhibition and its dissociation from acute toxicity in mouse hepatocytes. Environ Toxicol 18 243-251... 

Homoharringtonine (128) Alkaloid Homoharringtonine (Omacetaxine mepesuccinate Ceflatonin ) (128) Oncology Protein synthesis inhibition Phase Il/ni ChemGenex 738, 739... 

Protein synthesis inhibition—prokaryotes Protein synthesis inhibition—eukaryotes Mistranslation on ribosomes Nonsense mutation suppression DNA translation Phenotypic suppression Membrane leakiness Nucleic acid binding/precipitation... 

Protein synthesis inhibition. Buffer of the fresh root produced weak activity, IC50 158 pg protein/mL . 

Protein synthesis inhibition. Chromatographic fraction of the dried seed, in cell culture, was active on reticulocyte lysate of rabbits, inhibitory concentrationjf, 15.25 ng/ mL vo84. 

Timbrell et al. (1996) reported that much higher hydrazine concentrations were required in rat hepatocyte cultures in comparison to plasma concentrations in male Sprague-Dawley rats to elicit the following hepatic/hepatocellular effects lactate dehydrogenase leakage, ATP and GST depletion, increase in citrulline level, protein synthesis inhibition, taurine leakage and triglyceride accumulation. 

Emetine and cephaeline are both potent inhibitors of protein synthesis, inhibiting at the translocation stage. They display antitumour and antiviral as well as antiamoebic activity, but are too toxic for therapeutic use. In recent studies, O-methylpsychotrine has displayed fairly low effects on protein synthesis, but a quite potent ability to curb viral replication through inhibition of HIV-reverse transcriptase. This may give it potential in the treatment of AIDS. 

Anti-viral drugs use mechanisms that interfere with nucleic acid and protein synthesis, inhibiting their attachment to and penetration of host cells. Because the viruses frequently adapt their structures, their elimination is difficult. A research team in Cambridge19 are looking at what they call a mutator protein . This protein is made by our own cells and is released to sneak inside certain viruses and cause chaos and mutations in their genome. Unfortunately the AIDS virus has evolved a defence against this process, but it is useful for other viruses. 

Cylindrospermopsin resulted in a hepatotoxic alkaloid that is capable of inhibiting protein synthesis, and it appears to have a progressive effect on several other vital organs snch as the kidney in addition to the liver (Terao 1994 Falconer 1999). Cylindrospermopsin was shown to be a potent inhibitor of protein synthesis. The same stndies described the liver as the main target of this phyco-toxin, with four consecutive phases of the pathological changes in the liver protein synthesis inhibition, membrane proliferation, fat droplet accumulation, and cell death. 

Some biological effects may be mediated by reaction of the epoxy groups of trichothecenes with sulfhydryl groups on enzymes and binding of certain trichothecenes to membrane components. T-2 toxin rapidly affected glucose, nucleotide and amino acid transporters as well as calcium/ potassium channel activities in vitro indicating alteration of cell membrane functions independent of protein synthesis inhibition (Brunner and Morris, 1988). In pigs, DAS was... 

Feuerstein, G., Powell, J.A., Knower, A.T., Hunter, K.W. (1985). Monoclonal antibodies to T-2 toxin. In vitro neutralization of protein synthesis inhibition and protection of rats against lethal toxemia. J. Clin. Invest. 76 2134-8. 

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