Specific promoters

Depending on the peroxide class, the rates of decomposition of organic peroxides can be enhanced by specific promoters or activators, which significantly decrease the energy necessary to break the oxygen—oxygen bond. Such accelerated decompositions occur well below the peroxides normal appHcation temperatures and usually result in generation of only one usehil radical, instead of two. An example is the decomposition of hydroperoxides with multivalent metals (M), commonly iron, cobalt, or vanadium ... 

Adjuvants are substances which can modify the immune response of an antigen (139,140). With better understanding of the functions of different arms of the immune system, it is possible to explore the effects of an adjuvant, such that the protective efficacy of a vaccine can be improved. At present, aluminum salt is the only adjuvant approved for use in human vaccines. New adjuvants such as QS-21, 3D-MPL, MF-59, and other liposome preparations are being evaluated. Several of these adjuvants have been in clinical trial, but none have been approved for human use. IL-12 has been proposed as an adjuvant which can specifically promote T-helper 1 ceU response, and can be a very promising adjuvant for future vaccine development. 

FIGURE 13.15 Expression vectors carrying the promoter recognized by the RNA polymerase of bacteriophage SPG are useful for making RNA transcripts in vitro. SPG RNA polymerase works efficiently in vitro and recognizes its specific promoter with high specificity. 

In the second step, methacrolein is oxidized to methacrylic acid at a relatively lower temperature range of 250-350°C. A molybdenum-supported compound with specific promoters catalyzes the oxidation. 

Vascular gene therapy Transfer of dominant-negative receptors or suicide genes under the control of angiogenic endothelial cell specific promoters... 

HBV-based vectors efficiently target quiescent hepatocytes and HBV-specific promoter and enhancer elements allow hepatocyte specific gene expression (Protzer et al. 1999). In addition, a very favorable ratio of infectious to defective particles renders HBV-based vectors good candidates for liver-directed gene transfer. Improved HBV vectors, in which HBV gene expression was abolished (Untergasser and Protzer 2004), were used in chimpanzees to treat chronic HCV infection and did not show any toxicity (Shin et al. 2005). 

Figure 37-14. Alternative promoter use in the liver and pancreatic B cell glucokinase genes. Differential regulation of the glucokinase GK) gene is accomplished by the use of tissue-specific promoters. The B cell GK gene promoter and exon 1B are located about 30 kbp upstream from the liver promoter and exon 1L. Each promoter has a unique structure and is regulated differently. Exons 2-10 are identical in the two genes, and the GK proteins encoded by the liver and B cell mRNAs have identical kinetic properties.

The case of canola is extraordinary because of the very high level accumulations (50-fold) of leaf-type carotenoids in seeds when the gene was introduced under the seed-specific promoter, napin. The exalbuminous seeds of canola differ from those of genetically engineered rice cereal grains in that they have chloroplasts, which may explain the capacity for hyperaccumulation of carotenoids. 

Thai, A. L. V., Coste, E., Allen, J. M., Palmiter, R. D., and Weber, M. J. (1993). Identification of a neuron-specific promoter of human aromatic L-amino acid decarboxylase gene. Mol. Brain. Res 17 227-238. 

Lowings, P., Yavuzer, U., and Goding, C. (1992). Positive and negative elements regulate a melanocyte-specific promoter. Mol. Cell. Biol. 12 3653-3662. 

A bacterial two-hybrid system has been developed that, similar to the yeast system, functions via activation of transcription (Dove and Hochschild, 1998 Joung et al., 2000). RNA polymerase (RNAP) in E. coli consists of an enzymatic core composed of the a, (3, and (3 subunits in the stoichiometry a2(3(3, and one of several c factors that enable the enzyme to recognize specific promoters (Heilman and Chamberlin, 1988). Many bacterial transcriptional activator proteins bind the promoters they regulate and interact directly with subunits of RNAP. The most commonly observed contact is between activator proteins and the a subunit of RNAP (Ebright and Busby, 1995). The function of the a subunit is to initiate the assembly of RNAP by forming a dimer (Igarashi et al., 1991). 

The first reports on direct electrochemistry of a redox active protein were published in 1977 by Hill [49] and Kuwana [50], They independently reported that cytochrome c (cyt c) exhibited virtually reversible electrochemistry on gold and tin doped indium oxide (ITO) electrodes as revealed by cyclic voltammetry, respectively. Unlike using specific promoters to realize direct electrochemistry of protein in the earlier studies, recently a novel approach that only employed specific modifications of the electrode surface without promoters was developed. From then on, achieving reversible, direct electron transfer between redox proteins and electrodes without using any mediators and promoters had made great accomplishments. 

More recently, various modifications have been introduced to this basic retroviral system. The inclusion of the 5 end of the gag gene is shown to enhance levels of vector production by up to 200-fold. Additionally, specific promoters have been introduced in order to attempt to control expression of the inserted gene. Most work has focused upon the use of tissue-specific promoters in an effort to limit expression of the desired gene to a specific tissue type. 

Therefore, researchers reasoned that the natural switch with age of NRl s partner could explain why the NMDA receptor in adult brain has a much narrower window of time for cellular association to occur, and it might explain why adult animals find it harder to learn and register new information [26]. So a copy of the NR2B gene was linked to a forebrain-specific promoter that increases NR2B s expression in the adult mouse forebrain (Fig. 53-5A), thereby counteracting the natural decline of the NR2B expression in the adult. 

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