Mechanisms of Gene Regulation in Eukaryotes

There are several different forms of both a and subunits differing by only one or a few amino acids, and the forms that are present depend on the stage of development of an organism (Chapter 28). For example, the following temporal sequence shows the subunit types present in humans at various times after conception. 

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Outline the roles of coactivators and corepressors in transcription complexes. Contrast mechanisms of positive and negative gene regulation in eukaryotes. 

Metal ion homeostasis in prokaryotes has not yet provided a model for regulation in eukaryotes. The mechanisms for gene regulation in prokaryotes are proving to be as variable themselves as the mechanisms of transport. Despite great differences between eukaryotes and prokaryotes, it is still probable that their metal ion homeostasis mechanisms may sometimes be found to be similar. For the present, however, the mechanisms of prokaryotic metal ion regulation sometimes provide first hypotheses for constructing models of eukaryotic metal ion homeostasis. 

If the above cited data are corroborated in the future, it could serve as one the demonstrative examples of the originality of gene regulation mechanisms and of the action of gene modifiers in eukaryotes on the post-translational level. 

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