BIOL-UA 21 Chapter Notes - Chapter 7: Protein Structure, Alpha Helix, Repressor
Document Summary
7. 4 regulatory sequences in protein coding genes and the proteins through which. Repressor inhibit transcription and ar the functional converse of activators. Eukaryotic transcription is regulated by repressors as well. Constitutive expression = unregulated, abnormally high expression and results from the inactivation of a repressor that normally inhibits the transcription of these genes. Mutants in drosophila and c. elegans have been isolated that are defective in embryonic development because they express genes in cells where those genes are normally repressed. Mutations in these mutants inactivate repressors, leading to abnormal. Repressor-binding sites in dna have been identified by systematic linker scanning development mutation analysis. Mutation of an activator binding site leads to decreased expression of the linked reporter gene, whereas mutation of a repressor binding site leads to increased expression of a reporter gene. Reporter proteins that bind such sites can be purified and assayed using same biochemical techniques for activator proteins. Eukaryotic transcription repressors are the functional converse of activators.