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Related to repressor: repressor gene, Lac 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.
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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 ?
There was a constant increase in xylanase activity with xylan as the only carbon source while no any detectable xylanase activity was observed when the repressor glucose was present in medium with xylan.
Individuals with genotype II exhibited shorter body length than those with other genotypes, which might be related to the particular structure of ZNF132 as a transcriptional repressor.
If the segregation occurs, the V-GURT construct lose functionality and result on the suicide of plants grown from seeds that do not carry the repressor gene because the terminator gene will be expressed.
According to Salama, her team's findings support the idea that expansion of this family of repressor genes occurred in response to waves of retrotransposon activity.
These results suggest that Chrono functions as a core clock repressor, Toru Takumi from RIKEN added.
16, ns] did not differ significantly between the repressor and nonrepressor groups.
In the classic molecular genetic studies, prokaryotic promoters were believed to be regulated by a single specific regulatory protein, either a repressor and an activator, as originally identified in the lac operon regulation by LacI repressor.
Growth factor independent 1 transcription repressor (GFI1) on chromosome 1 is a gene not previously associated with tobacco smoke, but in this study eight CpG sites on this gene were differentially methylated in children of smokers.
The former diplomat's statements were made at the US trial of Paraguayan repressor Americo Norberto Pena Irala--who had fled to the US--accused of kidnapping and murdering the adolescent Joelito Filartiga in Asuncion in 1976, an incident made into the 1991 film One Man's War, starring Anthony Hopkins.
Repressor gens-tumor, as like that it's name showing, prevent from tumor creation with cell's growth set.
Another version of the video was then uploaded by a different YouTube user, who titled it 'It's easy to laugh at the occupation when you're the repressor (and a douche bag).