inducer

A molecule, usually a substrate of a specific enzyme pathway, that combines with and deactivates an active repressor (produced by a regulator gene); this allows an operator gene previously repressed to activate the structural genes controlled by it to result in enzyme production; a homeostatic mechanism for regulating enzyme production in an inducible enzyme system.

- embryonal i. any compound that will effect differentiation in the early stages of development.

- gratuitous i. an analog of a natural i. that is capable of inducing an operon while not serving as a substrate for the enzyme being induced.

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in·duc·er -'d(y)ü-sər n one that induces specif a substance that is capable of activating the transcription of a gene by combining with and inactivating a genetic repressor

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in·duc·er (in-dsґər) in molecular genetics, a molecule that causes a cell or organism to accelerate synthesis of an enzyme or sequence of enzymes in response to an environmental signal. The inducer often acts by antagonizing the action of a corresponding repressor, and may be a substrate of the enzyme or may be some other molecule, such as a hormone.