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Related to Repressors: repressor gene, aporepressor


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.
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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.


An end product of metabolism which represses the synthesis of enzymes in the metabolic pathway.
The product of a regulator gene that acts to repress the transcription of another gene.
References in periodicals archive ?
Experiments with ZNF 93, which shuts down L1PA retrotransposons, provided a striking illustration of the arms race between jumping genes and repressors.
Thus, we investigated differences in suppression of the recall of visual images between repressors and nonrepressors using the TNT paradigm.
Global regulators for carbon metabolism: CRP (cAMP receptor protein) and Cra (catabolite repressor activator).
Days later, the CCS said, "The 696 repressors identified by the CVJ and still enjoying impunity are the Praetorian Guard of a society that we want to change, in the same way that our disappeared companions wanted to change it and the landless campesinos today want to change it.
Aside from the question of why elites turn into repressors, however, readers will wonder why elitism arises in the first place.
Children who were identified as repressors were least likely to report somatic symptoms (Pediatr.
Individuals with true low anxiety score low on both anxiety and defensiveness, whereas repressors self-report low anxiety and high defensiveness and, on physiological measures, exhibit high arousal (Weinberger, 1990).
What we discovered is that the genes involved in these activities are normally off because there are proteins that act as repressors and prevent the genes from being turned on," notes Mark Estelle of the university's Institute for Cellular and Molecular Biology.
On the whole, the repressors were more socially and academically successful than their more "sensitized" classmates.
Some are activators, turning genes on and some are repressors, turning genes off.
Both the c1 and the c4 genes code for repressors of lytic growth.
His studies showed negative effects: grieving individuals who express strong negative emotions about their loss are worse off than the so-called repressors, who recover more rapidly.