The ligand binding domain of nuclear receptors, a family of ligand-activated transcription regulators; Ligand-binding domain (LBD) of nuclear receptor (NR): Nuclear receptors form a superfamily of ligand-activated transcription regulators, which regulate various physiological functions in metazoans, from development, reproduction, to homeostasis and metabolism. The superfamily contains not only receptors for known ligands but also orphan receptors for which ligands do not exist or have not been identified. The members of the family include receptors of steroids, thyroid hormone, retinoids, cholesterol by-products, lipids and heme. With few exceptions, NRs share a common structural organization with a central well conserved DNA binding domain (DBD), a variable N-terminal domain, a non-conserved hinge and a C-terminal ligand binding domain (LBD).

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gi 702011432   1 RSGLLCVDKIEKSQEAYLLAFEHYVNHRKHNIPHFWPKLLMKVTDLRMIGACHASRFLHMKVECPTELFPPLFLEV 76
Cdd:cd06935  168 RPGLACVERIEKLQDSFLLAFEHYINYRKHHVPHFWPKLLMKVTDLRMIGACHASRFLHMKVECPTELFPPLFLEV 243

The ligand binding domain of thyroid hormone receptor, a members of a superfamily of nuclear receptors; The ligand binding domain (LBD) of thyroid hormone receptors: Thyroid hormone receptors are members of a superfamily of nuclear receptors. Thyroid hormone receptors (TR) mediate the actions of thyroid hormones, which play critical roles in growth, development, and homeostasis in mammals. They regulate overall metabolic rate, cholesterol and triglyceride levels, and heart rate, and affect mood. TRs are expressed from two separate genes (alpha and beta) in human and each gene generates two isoforms of the receptor through differential promoter usage or splicing. TRalpha functions in the heart to regulate heart rate and rhythm and TRbeta is active in the liver and other tissues. The unliganded TRs function as transcription repressors, by binding to thyroid hormone response elements (TRE) predominantly as homodimers, or as heterodimers with retinoid X-receptors (RXR), and being associated with a complex of proteins containing corepressor proteins. Ligand binding promotes corepressor dissociation and binding of a coactivator to activate transcription. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, TR has a central well conserved DNA binding domain (DBD), a variable N-terminal domain, a flexible hinge and a C-terminal ligand binding domain (LBD).

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gi 702011432   1 RSGLLCVDKIEKSQEAYLLAFEHYVNHRKHNIPHFWPKLLMKVTDLRMIGACHASRFLHMKVECPTELFPPLFLEV 76
Cdd:cd06935  168 RPGLACVERIEKLQDSFLLAFEHYINYRKHHVPHFWPKLLMKVTDLRMIGACHASRFLHMKVECPTELFPPLFLEV 243

The ligand binding domain of thyroid hormone receptor, a members of a superfamily of nuclear receptors; The ligand binding domain (LBD) of thyroid hormone receptors: Thyroid hormone receptors are members of a superfamily of nuclear receptors. Thyroid hormone receptors (TR) mediate the actions of thyroid hormones, which play critical roles in growth, development, and homeostasis in mammals. They regulate overall metabolic rate, cholesterol and triglyceride levels, and heart rate, and affect mood. TRs are expressed from two separate genes (alpha and beta) in human and each gene generates two isoforms of the receptor through differential promoter usage or splicing. TRalpha functions in the heart to regulate heart rate and rhythm and TRbeta is active in the liver and other tissues. The unliganded TRs function as transcription repressors, by binding to thyroid hormone response elements (TRE) predominantly as homodimers, or as heterodimers with retinoid X-receptors (RXR), and being associated with a complex of proteins containing corepressor proteins. Ligand binding promotes corepressor dissociation and binding of a coactivator to activate transcription. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, TR has a central well conserved DNA binding domain (DBD), a variable N-terminal domain, a flexible hinge and a C-terminal ligand binding domain (LBD).

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gi 702011432   1 RSGLLCVDKIEKSQEAYLLAFEHYVNHRKHNIPHFWPKLLMKVTDLRMIGACHASRFLHMKVECPTELFPPLFLEV 76
Cdd:cd06935  168 RPGLACVERIEKLQDSFLLAFEHYINYRKHHVPHFWPKLLMKVTDLRMIGACHASRFLHMKVECPTELFPPLFLEV 243

The ligand binding domain (LBD) of retinoic acid receptor (RAR), a members of the nuclear receptor superfamily; The ligand binding domain (LBD) of retinoic acid receptor (RAR): Retinoic acid receptors are members of the nuclear receptor (NR) superfamily of ligand-regulated transcription factors. RARs mediate the biological effect of retinoids, including both naturally dietary vitamin A (retinol) metabolites and active synthetic analogs. Retinoids play key roles in a wide variety of essential biological processes, such as vertebrate embryonic morphogenesis and organogenesis, differentiation and apoptosis, and homeostasis. RARs function as heterodimers with retinoic X receptors by binding to specific RAR response elements (RAREs) found in the promoter regions of retinoid target genes. In the absence of ligand, the RAR-RXR heterodimer recruits the corepressor proteins NCoR or AMRT, and associated factors such as histone deacetylases or DNA-methyltransferases, leading to an inactive condensed chromatin structure, preventing transcription. Upon ligand binding, the corepressors are released, and coactivator complexes such as histone acetyltransferase or histone arginine methyltransferases are recruited to activate transcription. There are three RAR subtypes (alpha, beta, gamma), originating from three distinct genes. For each subtype, several isoforms exist that differ in their N-terminal region, allowing retinoids to exert their pleiotropic effects. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, retinoic acid receptors have a central well conserved DNA binding domain (DBD), a variable N-terminal domain, a non-conserved hinge and a C-terminal ligand binding domain (LBD).

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gi 702011432   1 RSGLLCVDKIEKSQEAYLLAFEHYVNHRKHNIPHFWPKLLMKVTDLRMIGACHASRFLHMKVECPTELfPPLFLEVFE 78
Cdd:cd06937  154 RQDLEEPDRVEKLQEPLLEALKIYARKRRPDKPHMFPKMLMKITDLRSISAKGAERVITLKMEIPGPM-PPLISEMLE 230

The ligand binding domain of peroxisome proliferator-activated receptors; The ligand binding domain (LBD) of peroxisome proliferator-activated receptors (PPAR): Peroxisome proliferator-activated receptors (PPARs) are members of the nuclear receptor superfamily of ligand-activated transcription factors. PPARs play important roles in regulating cellular differentiation, development and lipid metabolism. Activated PPAR forms a heterodimer with the retinoid X receptor (RXR) that binds to the hormone response element located upstream of the peroxisome proliferator responsive genes and interacts with co-activators. There are three subtypes of peroxisome proliferator activated receptors, alpha, beta (or delta), and gamma, each with a distinct tissue distribution. Several essential fatty acids, oxidized lipids and prostaglandin J derivatives can bind and activate PPAR. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, PPAR has a central well conserved DNA binding domain (DBD), a variable N-terminal regulatory domain, a flexible hinge a nd a C-terminal ligand binding domain (LBD).

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gi 702011432   1 RSGLLCVDKIEKSQEAYLLAFEHYV--NHRKHniPHFWPKLLMKVTDLRMIGACHASRFLHMKVECPTELFPPLFLEVFE 78
Cdd:cd06932  180 RPGLINRKPVERIQEHVLQALELQLkkNHPDS--PQLFAKLLQKMVDLRQLVTDHVQMVQQIKKTETDASLPPLLQEIYK 257

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gi 702011432  79 D 79
Cdd:cd06932  258 D 258

The ligand binding domain (LBD) of the Ecdysone receptor, a member of the nuclear receptors super family; The ligand binding domain (LBD) of the ecdysone receptor: The ecdysone receptor (EcR) belongs to the superfamily of nuclear receptors (NRs) of ligand-dependent transcription factors. Ecdysone receptor is present only in invertebrates and regulates the expression of a large number of genes during development and reproduction. ECR functions as a heterodimer by partnering with ultraspiracle protein (USP), the ortholog of the vertebrate retinoid X receptor (RXR). The natural ligands of ecdysone receptor are ecdysteroids#the endogenous steroidal hormones found in invertebrates. In addition, insecticide bisacylhydrazine used against pests has shown to act on EcR. EcR must be dimerised with a USP for high-affinity ligand binding to occur. The ligand binding triggers a conformational change in the C-terminal part of the EcR ligand-binding domain that leads to transcriptional activation of genes controlled by EcR. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, ec dysone receptors have a central well conserved DNA binding domain (DBD), a variable N-terminal domain, a non-conserved hinge and a C-terminal ligand binding domain (LBD).

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gi 702011432   1 RSGLLCVDKIEKSQEAYLLAFEHYV-NHRKHNIPHFWPKLLMKVTDLRMIG 50
Cdd:cd06938  154 RPGLLQPKKVEKIQEIYLEALRAYVdNRRPPSQRVIFAKLLSILTELRTLG 204

The ligand binding domain of REV-ERB receptors, members of the nuclear receptor superfamily; The ligand binding domain (LBD) of REV-ERB receptors: REV-ERBs are transcriptional regulators belonging to the nuclear receptor superfamily. They regulate a number of physiological functions including the circadian rhythm, lipid metabolism, and cellular differentiation. The LBD domain of REV-ERB is unusual in the nuclear receptor family by lacking the AF-2 region that is responsible for coactivator interaction. REV-ERBs act as constitutive repressors because of their inability to bind coactivators. REV-ERB receptors can bind to two classes of DNA response elements as either a monomer or heterodimer, indicating functional diversity. When bound to the DNA, they recruit corepressors (NcoR/histone deacetylase 3) to the promoter, resulting in repression of the target gene. The porphyrin heme has been demonstrated to function as a ligand for REV-ERB. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, REV-ERB receptors have a central well conserved DNA binding domain (DBD), a variable N-terminal domain, a non-conserved hinge and a C-terminal ligand binding domain (LBD).

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gi 702011432   1 RSGLLCVDKIEKSQEAYLLAFEHYVNHRKHNIPHFWPKLLMKVTDLRMIGACHASRFLHMKV 62
Cdd:cd06940  128 RSGLENVNLVEALQETLIRALRTLIAKNHPNEPSIFTKLLLKLPDLRTLNNLHSEKLLAFKV 189