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Related to Repressor Protein: 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 ?
On the other hand, by binding to C1 repressor protein, the gene product Lxc renders C1 repressor less likely to bind to other regions along the DNA (1, 9, 10, 13, 20).
The P1 repressor protein, encoded by the c1 gene, is responsible for maintaining the P1 prophage in the lysogenic state.
A repressor protein coding sequence with a promoter that is active all of the time; and
A recombinase coding sequence, controlled by a promoter that would be active at all times, except that it is also regulated by repressor protein, which can be overridden with tetracycline.
It also identifies the specific complex of proteins that promotes degradation of the repressor proteins.
The discovery also involves identifying the specific complex of proteins that interact or bind with the repressor proteins and promote their degradation.
It was renamed as HIRA because the most significant peptides were similar to Hir1p and Hir2p which were two histone gene repressor proteins from the yeast Saccharomyces cerevisiae.
In addition, cell proliferation repressor proteins, p27 and p21, also were induced in this in vitro model.