Genes expression maximization

Post-translational modification Maximizing gene expression 5.3 Gene therapy and gene repair... 

From a commercial point of view it is desirable to maximize the yield of protein in a fermentation. This means maximizing gene expression and important factors are ... 

Anti-arthritic effect. Oral administration of AJA, a cannabinoid acid devoid of psychoactivity, reduced joint tissue damage in rats with adjuvant arthritis. Peripheral blood monocytes (PBM) and synovial fluid monocytes (SFM) were isolated from healthy subjects and patients with inflammatory arthritis, respectively, treated with AJA (0-30 mM) in vitro, and then stimulated with lipopolysaccharide. Cells were harvested for messenger RNA (mRNA), and supernatants were collected for cytokine assay. Addition of AJA to PBM and SFM in vitro reduced both steady-state levels of interleukin-ly (IL-ly) mRNA and secretion of IL-ly in a concentration-dependent manner. Suppression was maximal (50.4%) at 10 mM AJA (p < 0.05 vs untreated controls, n = 7). AJA did not influence tumor necrosis factor-a (TNF-a) gene expression in or secretion from PBM . 

A number of factors for DOTAP-cholesterol/DNA complex preparation including the DNA/liposome ratio, mild sonication, heating, and extrusion were found to be crucial for improved systemic delivery maximal gene expression was obtained when a homogeneous population of DNA/liposome complexes (200-450 nm) was used. Cryoelectron microscopy showed that the DNA was condensed on the interior of liposomes between two lipid bilayers in these formulations, a factor that was thought to be responsible for the high transfection efficiency in vivo and for the broad tissue distribution (150). 

In addition to its hydrolase activity with maximal velocity at acidic pH, biotinidase also possesses biotinyl-transferase activity at physiological pH, resulting in the biotinylation of nucleophilic compounds such as histones [13]. This activity may play an important role in the regulation of gene expression [30]. Both hydrolase and transferase activities are affected in patients with biotinidase deficiency [13]. 

Data summarized in Table 21.1 demonstrate that the level of luciferase gene expression increases with an increase in the volume of injected DNA solution. The maximal level of luciferase protein achieved was approximately 350 ng/mg of extracted protein from the liver. We also demonstrated in a previous study that the volume required for an optimal transfection varies with animal weight (Liu, F. et al., 1999). The volume for a maximal level of gene expression was approximately 1.2ml, 1.6ml or 3.0ml for animals with a body weight of 11—13g, 18-20 g or 30-33 g, respectively. The estimated volume for an optimal activity in mice is approximately 8-12% of animal weight, which is higher than total blood, estimated to be 7.3% of the body weight in mice (Wu et al., 1981). 

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