Selection vector

Various grid search designs to select vectors x to evaluate fix). 

Number of drug resistant colonies formed following culture of cells obtained from collagenase-dissociated organs with metastatic foci composed of tumor cells transfected with a selective vector. 

Display the reference restriction sites by selecting Vector -> Restriction Sites to open the selection box. Transfer the desired enzyme sites to the Show box and click Apply Close to display the recombinant DNA (Figure 9.8). 

Apply energy and pole strength criteria to select vectors. 

Stable transfection of cells with selectable vectors... 

The production of selectable vectors for use in animals cells often used Szybalski s system or further developments based on selective protocols directed to the purine synthesis pathway, for example, Bacchetti and Graham [198], who transferred the Herpes simplex thymidine kinase into a human cell line, albeit with very low efficiency in 1977 and Mulligan and Berg [199] who developed a selection protocol for the expression of an E. coli gpt gene in a eukaryotic vector in 1981. 

The solution of the system (10.17) allows the search direction d (depending on the selected vector h) to be calculated. By using this direction, it is possible to obtain both a new feasible point and the new inequality constraint (passive or satisfied)... 

FIGURE 3. The scheme of cyanobacterial promoter-selection vector construction and the chloroplast promoter cloning in Synechocystis... 

Fig. 3. Gene disruption using the Cre-/oJt approach. In the targeting vector, exon 3 is flanked by directly repeated lox sites with a positive-negative selection cassette within these sites. The ganciclovir-sensitive targeted cells can undergo Cre-mediated homologous recombination, resulting in excision of the selection vector and genomic sequences intervening the lox sites.

The number of resultant colonies is dependent on the number of cells electroporated, the amount of DNA used and the type of targeting strategy employed. Most of the selection vectors we use are devoid of polyadenylation signals and yield 100-300 colonies per experiment Identical constructs bearing polyadenylation signals typically yield 5-10 times more colonies. The promoter used to drive positive selectable markers can also affect the electroporation efficiency we use the PGK promoter, which routinely yields 2-5 times more colonies than comparable vectors driven by SV40 enhancer sequences... 

Next, we will analytical deepen this principle and it will be extended to include the spin variable for determining the reactivity direction (chemical stereo-selection vector ). 

Pierce J.C., Sauer B., and Sternberg N. 1992. A positive selection vector for cloning high molecular weight DNA by the bacteriophage PI system Improved cloning efficacy. Proc. Natl. Acad. Sci. 89 2056-2060. 

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