c-Erb-A α Inhibitors
Chemical inhibitors of c-Erb-A α can modulate the activity of this protein through various mechanisms. Triiodothyronine (T3) and Thyroxine (T4) are endogenous ligands for c-Erb-A α, but when present in excess, they can inhibit the protein's function. T3, with its higher affinity, competes for c-Erb-A α binding sites, preventing the protein from interacting with its natural ligands, which are crucial for protein activation and transcription regulation. T4, despite its lower affinity, can still occupy these binding sites and similarly inhibit c-Erb-A α by blocking the binding of more potent activators, which in turn hampers the protein's transcriptional activity. Diphenylhydantoin binds to c-Erb-A α and alters its conformation, diminishing the protein's DNA binding efficiency and thus its regulatory function. Amiodarone impacts the biosynthesis of thyroid hormones and their binding to carrier proteins, consequently decreasing the bioavailability of hormones for c-Erb-A α activation and impairing the protein's regulatory role in transcription.
Furthermore, Propylthiouracil impedes the peripheral conversion of T4 to T3, leading to a reduction in T3 levels and a consequent lack of activation of c-Erb-A α. Raloxifene competes with estrogen for receptor sites, potentially affecting c-Erb-A α activity by altering coactivator availability. Ketoconazole's inhibition of cytochrome P450 enzymes results in altered steroid synthesis, which can indirectly influence c-Erb-A α function. Glucocorticoids can shift the balance of nuclear receptor coactivators and corepressors, thereby affecting c-Erb-A α activity. Lead(II) acetate and cadmium chloride can bind to specific protein sites, potentially changing c-Erb-A α's conformation and hindering its interaction with DNA. Each of these chemicals can impact c-Erb-A α's ability to regulate gene expression by influencing its ligand-binding capabilities, altering its conformation, or affecting its interaction with the transcriptional machinery.
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| Product Name | CAS # | Catalog # | QUANTITY | Price | Citations | RATING |
|---|---|---|---|---|---|---|
L-3,3′,5-Triiodothyronine, free acid | 6893-02-3 | sc-204035 sc-204035A sc-204035B | 10 mg 100 mg 250 mg | $41.00 $77.00 $153.00 | ||
Triiodothyronine, also known as T3, competes with c-Erb-A α for binding sites, inhibiting the protein’s ability to bind to its natural ligands, which are essential for its activation and subsequent transcriptional regulation. | ||||||
5,5-Diphenyl Hydantoin | 57-41-0 | sc-210385 | 5 g | $70.00 | ||
Diphenylhydantoin (Phenytoin) binds to thyroid hormone receptors such as c-Erb-A α and alters their conformation. This change in shape inhibits the protein's ability to regulate gene expression effectively, as it cannot bind to DNA as efficiently, thereby inhibiting its function. | ||||||
Amiodarone | 1951-25-3 | sc-480089 | 5 g | $318.00 | ||
Amiodarone interferes with thyroid hormone biosynthesis and can displace thyroid hormones from binding proteins. By doing so, it reduces the amount of thyroid hormone available for c-Erb-A α activation, leading to an inhibition of the protein's normal transcriptional regulation activities. | ||||||
6-Propyl-2-thiouracil | 51-52-5 | sc-214383 sc-214383A sc-214383B sc-214383C | 10 g 25 g 100 g 1 kg | $37.00 $56.00 $224.00 $1997.00 | ||
Propylthiouracil, although primarily known for inhibiting thyroid peroxidase, can also interfere with the peripheral conversion of T4 to T3. By reducing the levels of T3, which is a natural ligand for c-Erb-A α, the protein’s activity is inhibited due to a lack of ligand-induced activation. | ||||||
Raloxifene | 84449-90-1 | sc-476458 | 1 g | $802.00 | 3 | |
Raloxifene acts as a selective estrogen receptor modulator and has been shown to compete with estrogen for estrogen receptor sites, which can indirectly inhibit c-Erb-A α by influencing the availability of coactivators required for c-Erb-A α’s full transcriptional activity. Since estrogen receptors and thyroid hormone receptors can both compete for coactivators, the presence of raloxifene can lead to a functional inhibition of c-Erb-A α. | ||||||
Ketoconazole | 65277-42-1 | sc-200496 sc-200496A | 50 mg 500 mg | $63.00 $265.00 | 21 | |
Ketoconazole inhibits various cytochrome P450 enzymes involved in steroid synthesis. This can lead to decreased production of steroids that may regulate the activity of c-Erb-A α indirectly. By altering the steroid profile, ketoconazole can modulate the signaling pathways that intersect with the function of c-Erb-A α, leading to its functional inhibition. | ||||||
Hydrocortisone | 50-23-7 | sc-300810 | 5 g | $102.00 | 6 | |
Glucocorticoids, such as hydrocortisone, can inhibit c-Erb-A α indirectly by shifting the balance of nuclear receptor coactivators and corepressors in the cell. This can inhibit the transcriptional activity of c-Erb-A α by depriving it of necessary coactivator proteins or increasing the competition for these proteins, which are essential for the transcriptional regulation mediated by c-Erb-A α. | ||||||
Lead(II) Acetate | 301-04-2 | sc-507473 | 5 g | $85.00 | ||
Lead(II) acetate can bind to the sulfhydryl groups of cysteine residues in proteins. If c-Erb-A α has accessible cysteine residues that are critical for its function, lead binding could result in conformational changes that inhibit the protein's ability to bind DNA or interact with other transcriptional machinery, thereby inhibiting its function. | ||||||
Cadmium chloride, anhydrous | 10108-64-2 | sc-252533 sc-252533A sc-252533B | 10 g 50 g 500 g | $56.00 $183.00 $352.00 | 1 | |
Cadmium chloride is known to bind to and disrupt the function of various proteins. In the case of c-Erb-A α, cadmium can bind to critical sites, potentially altering the protein's conformation and inhibiting its ability to interact with its DNA response elements, thus inhibiting the protein's transcriptional regulatory function. | ||||||