Gene expression inhibition

The inhibitors of RNA polymerase, which generates RNA from DNA, inhibit a crucial step in gene expression. Inhibition of the eukaryotic form of RNA polymerase is used in cancer chemotherapy and is also an important experimental tool. For example, actinomy-cin D binds to the guanine residues in DNA and blocks the movement of the eukaryotic RNA polymerase. Specific inhibitors of bacterial RNA polymerase can be used as antibacterial agents. Most of these inhibitors like rifamycin bind to the prokaryotic enzyme. 

Gene expression inhibition. Chloroform/ methanol extract (1 1) of the dried leaf, in cell culture, was active on hepatoma-Cos-7, IC50 600.0 pg/mL vs TAT-dependent activation of HIV promoter hioassay - . Hepatotoxic activity. The leaf, taken orally by a female adult, was active - . A patient consumed 15 tablets of the leaf per day for 4 months. Approximately 1 year after stopping consumption, liver enzymes returned to normal and fatigue was no longer a complaint - ". Infusion of the dried leaf, taken orally by a female adult at variable doses, was active. The 60-year-old woman who took Lama tridentata for 10 months developed severe hepatitis for which no other cause could be found. Despite aggressive supportive therapy, the patient s condition deteriorated and required orthotropic liver transplantation - " . Dried leaves, administered orally to adults at variable doses, were active. A public warning has been issued by the US Centers for Disease Control based on reports of liver toxicity after use of Lama tridentata tea - " k Dried leaves, administered orally to adults of both sexes at variable doses, were active - ". The plant, administered orally to adults at variable doses, was active - ". Dried leaves, administered orally to adults at variable doses, were active. One case of hepatotoxicity induced by Larrea tridentata taken as a nutritional supplement was reported - ". Thirteen patients were identified for whom Larrea tridentata tincture for internal use was prescribed. Additionally, 20 female and three male patients were identified from whom an extract of Larrea tridentata in castor oil for... 

Gene expression inhibition. Hexane extract of the fruit, taken orally by male adults at a dose of 320 mg/day, significantly reduced nuclear estrogen and androgen receptors in the prostate . 

Measurement of the regulation of cAMP-dependent reporter gene expression, inhibition of constitutive mobilization of intracellular Ca2+, and enhancement of neurotransmitter release have also been used to detect inverse agonism in other Gi/o coupled receptor systems [see 8 for review] ... 

More recent studies have shown that vitamin E also has roles in cell signaling, by inhibition or inactivation of protein kinase C, and in modulation of gene expression, inhibition of cell proliferation, and platelet aggregation. These effects are specific for a-tocopherol and are independent of the antioxidant properties of the vitamin. 

Transactivation. Protein synthesis is initiated or inhibited by the action of the activated GR on DNA. The use of glucocorticoids leads to antiinflammatory effects by first controlling gene expression, which subsequentiy leads to the synthesis and/or suppression of inflammation regulatory proteins. 

Puromycin. Puromycin (19), elaborated by S. alboniger (1—4), inhibits protein synthesis by replacing aminoacyl-tRNA at the A-site of peptidyltransferase (48,49). Photosensitive analogues of (19) have been used to label the A-site proteins of peptidyltransferase and tRNA (30). Compound (19), and its carbocycHc analogue have been used to study the accumulation of glycoprotein-derived free sialooligosaccharides, accumulation of mRNA, methylase activity, enzyme transport, rat embryo development, the acceptor site of human placental 80S ribosomes, and gene expression in mammalian cells (51—60). 

Antisense therapy means the selective, sequence-specific inhibition of gene expression by single-stranded DNA oligonucleotides. By hybridizing to the target mRNA, which results in a subsequent double-helix formation, gene expression is blocked. This process can occur at any point between the conclusion of transcription and initiation of translation or even possibly during translation. 

Hepatitis B virus (HBV) Hepatocellular carcinoma Progenomic RNA Inhibition of viral gene expression... 

Activation of Mi, M3, and M5 mAChRs does not only lead to the generation of IP3 followed by the mobilization of intracellular Ca2+, but also results in the stimulation of phospholipase A2, phospholipase D, and various tyrosine kinases. Similarly, M2 and M4 receptor activation does not only mediate the inhibition of adenylyl cyclase, but also induces other biochemical responses including augmentation of phospholipase A2 activity. Moreover, the stimulation of different mAChR subtypes is also linked to the activation of different classes of mitogen-activated protein kinases (MAP kinases), resulting in specific effects on gene expression and cell growth or differentiation. 

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