Transcription factors continued regulation

Transcription Factors that Regulate Flavonoid Biosynthetic Genes — continued... 

Transcription factors are known to be substrates of HATs, whereas the enzymes responsible for the acetylation of nonnuclear proteins in many cases are not well known (55). The number of proteins that are regulated by acetylation will continue to increase as method to detect protein acetylation improves. Acetylation of nonhistone proteins can change protein-protein interaction, regulate enzymatic activity, and increase protein stability by suppressing ubiquitinylation (55). 

The hormonal forms of vitamin A are all-frans-retinoic acid and 9-cfs-retinoic acid. The hormonal form of vitamin D is 1,25-dihydroxyvitamin D3, and that of thyroid hormone is T3. These hormones act within the nucleus, where they bind to special proteins. These proteins are classed as transcription factors. Various transcription factors bind to the regulatory regions of all genes and influence the rate of transcription (Figure 9.60). Many genes are continuously transcribed, and here the term "basal level of transcription" is used to describe the rate of transcription. In cases where the gene is regulated, special transcription factors are used to enhance or inhibit the basal level of transcription. 

Theoretical models of bio-macromolecules are concerned with the development of efficient drugs, the mechanisms of signal transduction, and gene regulation by transcription factors. All these phenomena have in common the capital role played by intermolecular interactions between tlie partners and their ability to recognize patterns. The current developments in structural genomics are, however, continuously... 

The synthesis of the transcription factor C-myc is tightly regulated in normal cells, and it is expressed only during the S phase of the cell cycle. In a large number of tumor types, this regulated expression is lost, and c-myc becomes inappropriately expressed or overexpressed throughout the cell cycle, driving cells continuously to proliferation. 

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