1. Introduction: What is the thyroid hormone receptor, and what does it do?
The thyroid hormone receptor (TRT) is a receptor that binds to thyroid hormone (TH). It is a G protein-coupled receptor. Thus it can be activated by agonist therapy and inhibited by antagonist therapy.
The function of the TRT has multiple subtypes. Some of the functional subtypes are as follows.
1. Thyroid Hormone Receptor alpha (THRA) alpha(2)subunit: This receptor consists of two α subunits and one β subunit. THRA α(2)subunits mediate TH signaling, whereas THRA β(3)subunits mediate TH resistance in target cells. THRA β(3)subunits have different roles in tissues such as the adrenal cortex, brain, heart, and kidney. This receptor is involved in developing type 2 diabetes mellitus and obesity-induced insulin resistance in mice.
2. Thyroid Hormone Receptor β (THRB) beta-subunit: The presence of this receptor on the Thyroid Hormone Receptors has been reported to enhance the secretion of thyroid hormones from the thyroid gland into the blood circulation through stimulation of specific pathways, including atrial natriuretic factor pathway, the release of epinephrine by sympathetic nerve fibers, adrenal cortical natriuretic peptide pathway and hepatic portal vein endothelial relaxation pathway .
3. Thyroid Hormone Receptor δ (THRd) delta-subunit: This receptor consists of two heterodimers of ThrA and ThrB domains . In the prostate gland, this type of receptor mediates endocrine control over growth hormone secretion from these glands . Several studies have reported that THRd receptors are expressed in human breast cancer cells
. In addition, THR receptors have also been implicated in glioblastoma multiforme tumor cell migration via inhibition by opioid peptides such as dynorphin D . In women’s breast cancer cells, it is also involved in programmed cell death gene regulation via regulation of p53 gene expression through the TGFβ signaling pathway .
2. The structure of the thyroid hormone receptor.
In this article, I will explain the structure of the thyroid hormone receptor. I will also discuss its possible function(s) and how the presence of certain hormones may influence these functions.
The thyroid hormone receptor (TR) is a G-protein coupled receptor (GPCR), which means that G-protein coupled receptors activate it. GPCR is a family of proteins. Several GPCRs, including the β-adrenergic receptor, histamine H2-receptor, and serotonin 5-HT2A receptor.
There is a crucial difference between these receptors in that they each bind to different classes of G proteins: α1β1 or α2β2 has an affinity for α-subunits (the binding site on the protein) and β-subunits (the binding site on the protein) but not for β-subunits. γ2γ2 has a relationship with both types of subunits, and γ3γ3 has an affinity for both types.
3. The function of the thyroid hormone receptor.
The thyroid hormone receptor is a post-transcriptional DNA regulatory element that acts as a transcription factor. 1 The thyroid hormone receptor can be activated by thyrotropin-releasing hormone (TRH) or by endogenous activators such as thyroxine (T4) and triiodothyronine (T3).
There are two primary forms of TRH receptors, TRHR1 and TRHR2. The first, TRHR1, is present in most tissues in the human body. It is expressed in all tissues where thyroid hormones bind, such as the brain, heart, kidneys, lymph nodes, and liver. The second, TRHR2, is only expressed in testes and ovaries but remains inactive during gestation.
4. The role of the thyroid hormone receptor in the body.
The thyroid hormone receptor (TR), a protein found in the nucleus of every cell, is thought to regulate countless cellular functions, including metabolism, growth, development, reproduction, and survival. A large part of TR’s role is to help control hormone levels. When insufficient TR activity, the body enters “hypothyroidism” (low thyroid levels). A healthy thyroid level allows for the more efficient functioning of the body.
Both endogenous and exogenous hormones can activate the thyroid hormone receptor. There are two types of receptors: α-subunit and β-subunit. The α-subunit forms a heterodimer with either TSH or T4 and is associated with binding both iodinated T4 (T4) and T3 molecules to thyroid tissue. Together these two molecules are called thyroglobulin (TG) and stimulate thyroid hormone synthesis and secretion from the gland.
The hypothalamic-pituitary-thyroid axis controls circulating thyroglobulin levels; anti-TG antibodies suppress this axis, leading to low circulating thyroglobulin levels, which can cause hypothyroidism. In addition to circulating TG levels, it is also essential that about 70% of plasma TG originates from tissues such as adipose tissue rather than the liver (nonesterified fatty acids).
5. The importance of the thyroid hormone receptor.
The thyroid hormone receptor is a protein that binds to the thyroid hormone receptors in the body and is therefore known as a “thyroid hormone receptor.” It is essential for thyroid function because it regulates gene expression in the cells of the thyroid gland.
This regulation of gene expression may play a role in controlling many aspects of human physiology, including body weight (weight gain or loss), appetite, metabolism, and systemically mediated functions such as cognitive function.
6. The implications of the thyroid hormone receptor.
It’s a known fact that the human body produces thyroid hormones. But what is it doing? Why do we need this hormone? How does it affect our health? What are the implications of its presence in our bodies, and what can we do to control its effects on our health?
The thyroid hormone receptor (TR) is an essential gene located at chromosome 17q21-q24 that binds to the thyroid hormone receptors. Its role in regulating calcium homeostasis is not fully understood.
Recently, researchers have reported that mutations in TR may be associated with increased cancer risk. Researchers found that having these mutations led to a higher cancer risk than carriers of other mutations of TR. However, no mutations were observed in most tissues examined from individuals and families with a history of cancer and no family history of cancer.
7. Conclusion: The thyroid hormone receptor is a vital part of the body’s function.
A thyroid hormone receptor (thyroglobulin, TGR) is a functional receptor for thyroid hormones. It is discovered in the cell membranes of multiple tissues, including the thyroid gland and the placenta. Thyroid hormone receptors are also found in many other tissues, including neurons and immune cells, as well as in fibroblasts and endothelial cells.
Several analyses displayed that tumor development is inhibited by thyroglobulin expression, associated with cancer growth suppression of the human tumor cell line HCT-116. Furthermore, certain viruses, such as the herpes simplex virus (HSV), can enter human cells and inhibit their proliferation through a thyroglobulin-dependent mechanism.