Wiktionary
n. 1 Anything that represses. 2 (context genetics English) Any protein that binds to DNA and thus regulates the expression of genes by decreasing the rate of transcription
WordNet
n. an agent that represses [syn: represser]
Wikipedia
In molecular genetics, a repressor is a DNA- or RNA-binding protein that inhibits the expression of one or more genes by binding to the operator or associated silencers. A DNA-binding repressor blocks the attachment of RNA polymerase to the promoter, thus preventing transcription of the genes into messenger RNA. An RNA-binding repressor binds to the mRNA and prevents translation of the mRNA into protein. This blocking of expression is called repression.
Usage examples of "repressor".
However, if repressors had seen the film three times, they were fairly relaxed during the medical procedure.
Laenea nodded toward a nearby group of people, hyper and shrill on sleep repressors and energizers.
Within Cedric's pituitary gland, the deadly new proteins were able to bind themselves to the repressors that covered the genes for the death hormone.