repressor

(redirected from Gene repression)
Also found in: Dictionary, Thesaurus, Medical, Legal.
Related to Gene repression: regulator gene, regulatory gene, negative gene control, gene switch, Gene activation, aporepressor

repressor:

see nucleic acidnucleic acid,
any of a group of organic substances found in the chromosomes of living cells and viruses that play a central role in the storage and replication of hereditary information and in the expression of this information through protein synthesis.
..... Click the link for more information.
.

Repressor

 

a special regulating protein formed in bacterial cells that halts transcription, which is the synthesis of messenger ribonucleic acid (m-RNA) from a specific operon (a group of genes that carry out the synthesis of functionally related enzymes). The number of different repressors corresponds to the number of operons.

Unlike other proteins, a repressor present in a cell consists of ten to 20 molecules. The synthesis of m-RNA ceases when a repressor combines with an operator, which is the regulating part of an operon. An effector, for example, lactose in a lactose operon, interacts with a repressor to form a complex that inactivates and produces a reversible spatial change in a repressor molecule. This type of repressor can no longer combine with an operator and, as a result, m-RNA synthesis resumes.

repressor

[ri′pres·ər]
(biochemistry)
An end product of metabolism which represses the synthesis of enzymes in the metabolic pathway.
(genetics)
The product of a regulator gene that acts to repress the transcription of another gene.