noun, plural: regulator genes
A gene that is involved in the production of a substance that controls or regulates the expression of one or more genes, such as the gene that codes for a repressor protein that inhibits the activity of an operator gene.
For instance, a regulator gene codes for repressor protein that binds to operator gene, which consequently prevents production of a particular enzyme. When that enzyme is needed again, a specific regulatory metabolite inhibits the repressor so that the enzyme is produced.
See also: gene regulation.