Regulation 35 sequence

Waring, J. F. et al., Development of a DNA microarray for toxicology based on hepato-toxin-regulated sequences, EHP Toxicogenomics, 111, 53, 2003. 

Hexokinase is an enzyme that is mentioned at an early point in most biochemistry courses, since this enzyme is required for the first step in the body s utilization of glucose. The promoter for the hexokinase gene is shown here. This promoter consists of about 160 base pairs, and contains a TATA box (AATAA underlined), a CCAAT box [also underlined), and a short sequence of DNA that is regulated by a hormone. The hormone-regulated sequence is CCACGTCA (underlined). This short sequence of DNA is one of many types of "response elements" that occur in the genome. Specifically, CCACGTCA is called the cyclic AMP response element, for reasons that are explained later. This response element occurs in the hexokinase promoter, just a few nucleotides beyond the CCAAT box (Osawa rf a., 1996) ... 

Embryological development is a highly conserved, highly regulated sequence of events in which many processes must be activated or deactivated... 

In a mammalian cell, a large number (about 10 000) of mRNAs have a low abundance, i.e., a few copies per cell. Many strategies have been designed to enrich for specific mRNAs or to recognize certain clones (Section 2.5.2.2) otherwise many clones would have to be analyzed (Table 10.1). Subtractive hybridization depletes the sample of nonspecific mRNA in order to enrich for the mRNA sought. It is particularly suitable for isolating tissue-specific or developmental regulated sequences or clones derived from mRNA induced by external factors. 

Using cell-specific transcription regulation sequences (binding elements such as promoters or enhancers) is another way to target ceUs without modification of the gene deUvery vehicle, which aUows for ceU targeting with known deUvery and release kinetics without having to repeat the same work for modified... 

In nature QB and MS2 infect bacteria like Escherichia coli. The life cycle of the virus consists of a regulated sequence of processes (Fig. 6) (1) translation of viral RNA by the host s machinery yielding the virus dependent subunit of the specific RNA replicase, (2) RNA replication by the specific enzyme yielding minus- and lateron plus-strands, (3) translation of viral RNA leading to A-protein, coat protein and lysis protein, (4) formation of virus particles and (5) lysis of the bacterial cell. 

Both catenanes and knots can bring together remote DNA sequences and may be important in transcription regulation and genetic recombination... 

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