Page last updated: 2024-10-24

negative regulation of DNA-templated transcription initiation

Definition

Target type: biologicalprocess

Any process that stops, prevents, or reduces the frequency, rate or extent of DNA-templated transcription initiation. [GOC:mah, GOC:txnOH]

Negative regulation of DNA-templated transcription initiation is a complex process that involves the suppression of gene expression at the level of transcription initiation. This process is essential for maintaining cellular homeostasis and ensuring that genes are only expressed when and where they are needed.

Transcription initiation is the first step in gene expression, where the DNA sequence of a gene is transcribed into a messenger RNA (mRNA) molecule. This mRNA molecule then serves as a template for protein synthesis.

Negative regulation of transcription initiation involves the binding of specific proteins called repressors to DNA sequences called operator sites. These operator sites are located near the start site of transcription, and the binding of repressors to these sites prevents the binding of RNA polymerase, the enzyme responsible for transcribing DNA into mRNA.

There are several mechanisms by which repressors can inhibit transcription initiation. One mechanism involves the direct blocking of RNA polymerase binding to the promoter. Another mechanism involves the recruitment of other proteins that modify the chromatin structure around the promoter region, making it less accessible to RNA polymerase.

Repressor proteins can be regulated by a variety of factors, including:

* **Small molecules:** Some repressors are activated or deactivated by the binding of small molecules, such as hormones or metabolites.
* **Other proteins:** Some repressors are regulated by the binding of other proteins, which can either activate or inhibit their function.
* **Environmental signals:** Some repressors are regulated by environmental signals, such as temperature or nutrient availability.

The regulation of transcription initiation is essential for a wide range of cellular processes, including:

* **Cell differentiation:** Different cell types express different sets of genes, and this is achieved through the regulation of transcription initiation.
* **Development:** The development of an organism from a single cell into a complex multicellular organism is driven by the regulated expression of genes.
* **Response to environmental stimuli:** Cells can respond to environmental changes, such as stress or nutrient deprivation, by altering the expression of specific genes.
* **Disease:** Dysregulation of transcription initiation can contribute to a wide range of diseases, including cancer, metabolic disorders, and autoimmune diseases.

Overall, negative regulation of DNA-templated transcription initiation is a fundamental process that plays a critical role in the regulation of gene expression and the maintenance of cellular homeostasis.'
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Proteins (1)

ProteinDefinitionTaxonomy
Thyroid hormone receptor alphaA thyroid hormone receptor alpha that is encoded in the genome of human. [PRO:HJD, UniProtKB:P10827]Homo sapiens (human)

Compounds (17)

CompoundDefinitionClassesRoles
amiodaroneamiodarone : A member of the class of 1-benzofurans that is 1-benzofuran substituted by a butyl group at position 2 and a 4-[2-(diethylamino)ethoxy]-3,5-diiodobenzoyl group at position 3. It is a cardiovascular drug used for the treatment of cardiac dysrhythmias.

Amiodarone: An antianginal and class III antiarrhythmic drug. It increases the duration of ventricular and atrial muscle action by inhibiting POTASSIUM CHANNELS and VOLTAGE-GATED SODIUM CHANNELS. There is a resulting decrease in heart rate and in vascular resistance.
1-benzofurans;
aromatic ketone;
organoiodine compound;
tertiary amino compound
cardiovascular drug
3,3',5-triiodothyroacetic acidtiratricol : A monocarboxylic acid that is (4-hydroxy-3,5-diiodophenyl)acetic acid in which the phenolic hydroxy group has been replaced by a 4-hydroxy-3-iodophenoxy group. It is a thyroid hormone analogue that has been used in the treatment of thyroid hormone resistance syndrome.
3,3',5-triiodothyropropionic acidaromatic ether
thyroxinethyroxine : An iodothyronine compound having iodo substituents at the 3-, 3'-, 5- and 5'-positions.

Thyroxine: The major hormone derived from the thyroid gland. Thyroxine is synthesized via the iodination of tyrosines (MONOIODOTYROSINE) and the coupling of iodotyrosines (DIIODOTYROSINE) in the THYROGLOBULIN. Thyroxine is released from thyroglobulin by proteolysis and secreted into the blood. Thyroxine is peripherally deiodinated to form TRIIODOTHYRONINE which exerts a broad spectrum of stimulatory effects on cell metabolism.
2-halophenol;
iodophenol;
L-phenylalanine derivative;
non-proteinogenic L-alpha-amino acid;
thyroxine;
thyroxine zwitterion
antithyroid drug;
human metabolite;
mouse metabolite;
thyroid hormone
triiodothyronine3,3',5-triiodo-L-thyronine : An iodothyronine compound having iodo substituents at the 3-, 3'- and 5-positions. Although some is produced in the thyroid, most of the 3,3',5-triiodo-L-thyronine in the body is generated by mono-deiodination of L-thyroxine in the peripheral tissues. Its metabolic activity is about 3 to 5 times that of L-thyroxine. The sodium salt is used in the treatment of hypothyroidism.

Triiodothyronine: A T3 thyroid hormone normally synthesized and secreted by the thyroid gland in much smaller quantities than thyroxine (T4). Most T3 is derived from peripheral monodeiodination of T4 at the 5' position of the outer ring of the iodothyronine nucleus. The hormone finally delivered and used by the tissues is mainly T3.
2-halophenol;
amino acid zwitterion;
iodophenol;
iodothyronine
human metabolite;
mouse metabolite;
thyroid hormone
mifepristoneMifepristone: A progestational and glucocorticoid hormone antagonist. Its inhibition of progesterone induces bleeding during the luteal phase and in early pregnancy by releasing endogenous prostaglandins from the endometrium or decidua. As a glucocorticoid receptor antagonist, the drug has been used to treat hypercortisolism in patients with nonpituitary CUSHING SYNDROME.3-oxo-Delta(4) steroid;
acetylenic compound;
tertiary amino compound
abortifacient;
contraceptive drug;
hormone antagonist;
synthetic oral contraceptive
tetraiodothyroacetic acid3,3',5,5'-tetraiodothyroacetic acid : A monocarboxylic acid that is thyroacetic acid carrying four iodo substituents at positions 3, 3', 5 and 5'.

tetraiodothyroacetic acid: RN given refers to parent cpd; structure
2-halophenol;
aromatic ether;
iodophenol;
monocarboxylic acid
apoptosis inducer;
human metabolite;
thyroid hormone
3,5-dimethyl-3'-isopropyl-l-thyronine3,5-dimethyl-3'-isopropyl-L-thyronine: RN given refers to (L)-isomer
pregna-4,17-diene-3,16-dionepregna-4,17-diene-3,16-dione: steroid from guggulu extract; RN & N1 from C1 Form index; RN given refers to cpd without isomeric designation; structure in first source; antagonist of farnesoid X receptor3-hydroxy steroidandrogen
gc 1 compoundGC 1 compound: structure in first sourcediarylmethane
kb 141KB 141: an anticholesteremic agent; structure in first source
kb 130015KB 130015: structure in first source
cgs 23425CGS 23425: structure given in first source
3,5-dibromo-4-(4-hydroxy-3-isopropylphenoxy)phenylacetic acid3,5-dibromo-4-(4-hydroxy-3-isopropylphenoxy)phenylacetic acid: a thyroid receptor beta1 agonist; structure in first source
kb 21153-((3,5-dibromo-4-(4-hydroxy-3-(1-methylethyl)phenoxy)phenyl)amino)-3-oxopropanoic acid: a thyroid hormone receptor agonist with anticholesteremic activity
fg-4592roxadustat : An N-acylglycine resulting from the formal condensation of the amino group of glycine with the carboxy group of 4-hydroxy-1-methyl-7-phenoxyisoquinoline-3-carboxylic acid. It is an inhibitor of hypoxia inducible factor prolyl hydroxylase (HIF-PH).

roxadustat: structure in first source
aromatic ether;
isoquinolines;
N-acylglycine
EC 1.14.11.2 (procollagen-proline dioxygenase) inhibitor;
EC 1.14.11.29 (hypoxia-inducible factor-proline dioxygenase) inhibitor
mgl-3196resmetirom: a thyroid hormone receptor-beta agonist