How is Gene Expression Regulated in Eukaryotic Cells?
Activator: Protein in eukaryotic cells that binds to consensus sequences in regulatory promoters or enhancers and affects transcription initiation by stimulating or inhibiting the assembly of the basal transcription apparatus. Enhancer: Sequence that stimulates maximal transcription of distant gene; affects only genes on the same DNA molecule, contains short consensus sequences, is not fixed in relation to the transcription start site, can stimulate almost any promoter in its vicinity, and may be upstream or downstream of the gene. The function of an enhancer is independent of sequence orientation. Eucromatin: The more open, unraveled from of eukaryotic chromatin that is available for transcription. Exon: Coding region of a split gene(a gene that is interrupted by introns). After processing the exons remain in messenger RNA. Heterochromatin: Nontranscribed eukaryotic chromatin that is so highly compacted that it is visible with a light microscope during interphase. Histone: A small pro
