1. A molecule that binds to a repressor protein to enable it to block gene transcription in cells.
Usage: molecular biology; genetics

Examples

• The corepressor molecule attaches to the repressor protein, allowing it to bind to the operator region.
• In the trp operon, tryptophan acts as a corepressor that shuts down gene expression when tryptophan levels are high.
• Without a corepressor, the repressor protein cannot effectively block transcription of the target genes.
• Corepressors are essential regulatory molecules in prokaryotic gene control systems.
• The binding of the corepressor to the repressor causes a conformational change that enables DNA binding.