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Definition of "repressor" [repressor]

  • One that represses. (noun)
  • Genetics A protein that binds to an operator, blocking transcription of an operon and the enzymes for which the operon codes. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Use "repressor" in a sentence
  • "This control function had been defined genetically by the work of Jacob and Monod, but a repressor is made in such small amounts that it was an extraordinarily elusive biochemical entity."
  • "A repressor is a protein product made by one gene in the bacterium in order to control a second gene by turning it off when its product is not wanted."
  • "Now, then, the repressor is responsible for immunity."