DNA-binding domain of retinoid X receptor (RXR) is composed of two C4-type zinc fingers; DNA-binding domain of retinoid X receptor (RXR) is composed of two C4-type zinc fingers. Each zinc finger contains a group of four Cys residues which co-ordinates a single zinc atom. RXR functions as a DNA binding partner by forming heterodimers with other nuclear receptors including CAR, FXR, LXR, PPAR, PXR, RAR, TR, and VDR. All RXR heterodimers preferentially bind response elements composed of direct repeats of two AGGTCA sites with a 1-5 bp spacer. RXRs can play different roles in these heterodimers. RXR acts either as a structural component of the heterodimer complex, required for DNA binding but not acting as a receptor, or as both a structural and a functional component of the heterodimer, allowing 9-cis RA to signal through the corresponding heterodimer. In addition, RXR can also form homodimers, functioning as a receptor for 9-cis RA, independently of other nuclear receptors. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, RXR 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).

                       10        20        30        40        50        60        70
               ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 9955274   6 HICAICGDRSSGKHYGVYSCEGCKGFFKRTVRKDLTYTCRDNKDCLIDKRQRNRCQYCRYQKCLAMGMKREAVQEER 82
Cdd:cd06956  1 HICAICGDRASGKHYGVYSCEGCKGFFKRTVRKDLTYTCRDNKDCLIDKRQRNRCQYCRYQKCLAMGMKREAVQEER 77

DNA-binding domain of retinoid X receptor (RXR) is composed of two C4-type zinc fingers; DNA-binding domain of retinoid X receptor (RXR) is composed of two C4-type zinc fingers. Each zinc finger contains a group of four Cys residues which co-ordinates a single zinc atom. RXR functions as a DNA binding partner by forming heterodimers with other nuclear receptors including CAR, FXR, LXR, PPAR, PXR, RAR, TR, and VDR. All RXR heterodimers preferentially bind response elements composed of direct repeats of two AGGTCA sites with a 1-5 bp spacer. RXRs can play different roles in these heterodimers. RXR acts either as a structural component of the heterodimer complex, required for DNA binding but not acting as a receptor, or as both a structural and a functional component of the heterodimer, allowing 9-cis RA to signal through the corresponding heterodimer. In addition, RXR can also form homodimers, functioning as a receptor for 9-cis RA, independently of other nuclear receptors. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, RXR 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).

                       10        20        30        40        50        60        70
               ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 9955274   6 HICAICGDRSSGKHYGVYSCEGCKGFFKRTVRKDLTYTCRDNKDCLIDKRQRNRCQYCRYQKCLAMGMKREAVQEER 82
Cdd:cd06956  1 HICAICGDRASGKHYGVYSCEGCKGFFKRTVRKDLTYTCRDNKDCLIDKRQRNRCQYCRYQKCLAMGMKREAVQEER 77

c4 zinc finger in nuclear hormone receptors;

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 9955274      7 ICAICGDRSSGKHYGVYSCEGCKGFFKRTVRKDLTYTCRDNKDCLIDKRQRNRCQYCRYQKCLAMGMKRE 76
Cdd:smart00399  1 LCCVCGDHASGFHFGVCSCRACKAFFRRTVNLRYKYRCDRKNNCSINKRYRCRCRACRLKKCLGVGMDPE 70

DNA-binding domain of retinoid X receptor (RXR) is composed of two C4-type zinc fingers; DNA-binding domain of retinoid X receptor (RXR) is composed of two C4-type zinc fingers. Each zinc finger contains a group of four Cys residues which co-ordinates a single zinc atom. RXR functions as a DNA binding partner by forming heterodimers with other nuclear receptors including CAR, FXR, LXR, PPAR, PXR, RAR, TR, and VDR. All RXR heterodimers preferentially bind response elements composed of direct repeats of two AGGTCA sites with a 1-5 bp spacer. RXRs can play different roles in these heterodimers. RXR acts either as a structural component of the heterodimer complex, required for DNA binding but not acting as a receptor, or as both a structural and a functional component of the heterodimer, allowing 9-cis RA to signal through the corresponding heterodimer. In addition, RXR can also form homodimers, functioning as a receptor for 9-cis RA, independently of other nuclear receptors. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, RXR 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).

                       10        20        30        40        50        60        70
               ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 9955274   6 HICAICGDRSSGKHYGVYSCEGCKGFFKRTVRKDLTYTCRDNKDCLIDKRQRNRCQYCRYQKCLAMGMKREAVQEER 82
Cdd:cd06956  1 HICAICGDRASGKHYGVYSCEGCKGFFKRTVRKDLTYTCRDNKDCLIDKRQRNRCQYCRYQKCLAMGMKREAVQEER 77

DNA-binding domain of the TR2 and TR4 (human testicular receptor 2 and 4) is composed of two C4-type zinc fingers; DNA-binding domain of the TR2 and TR4 (human testicular receptor 2 and 4) is composed of two C4-type zinc fingers. Each zinc finger contains a group of four Cys residues which coordinates a single zinc atom. TR2 and TR4 interact with specific DNA sites upstream of the target gene and modulate the rate of transcriptional initiation. TR4 and TR2 are orphan nuclear receptors; the physiological ligand is as yet unidentified. TR2 is abundantly expressed in the androgen-sensitive prostate. TR4 transcripts are expressed in many tissues, including central nervous system, adrenal gland, spleen, thyroid gland, and prostate. It has been shown that human TR2 binds to a wide spectrum of natural hormone response elements (HREs) with distinct affinities suggesting that TR2 may cross-talk with other gene expression regulation systems. The genes responding to TR2 or TR4 include genes that are regulated by retinoic acid receptor, vitamin D receptor, and peroxisome proliferator-activated receptor. TR4/2 binds to HREs as dimers. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, TR2-like receptors have 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 9955274   7 ICAICGDRSSGKHYGVYSCEGCKGFFKRTVRKDLTYTCRDNKDCLIDKRQRNRCQYCRYQKCLAMGMKREAVQEERQ 83
Cdd:cd06967  5 LCVVCGDKASGRHYGAVSCEGCKGFFKRSIRKNLGYSCRGSKDCVINKHHRNRCQYCRLQKCLAMGMKSDSVQCERK 81

DNA-binding domain of heptocyte nuclear factor 4 (HNF4) is composed of two C4-type zinc fingers; DNA-binding domain of hepatocyte nuclear factor 4 (HNF4) is composed of two C4-type zinc fingers. Each zinc finger contains a group of four Cys residues which co-ordinates a single zinc atom. HNF4 interacts with a DNA site, composed of two direct repeats of AGTTCA with 1 bp spacer, which is upstream of target genes and modulates the rate of transcriptional initiation. HNF4 is a member of the nuclear receptor superfamily. HNF4 plays a key role in establishing and maintenance of hepatocyte differentiation in the liver. It is also expressed in gut, kidney, and pancreatic beta cells. HNF4 was originally classified as an orphan receptor, but later it is found that HNF4 binds with very high affinity to a variety of fatty acids. However, unlike other nuclear receptors, the ligands do not act as a molecular switch for HNF4. They seem to constantly bind to the receptor, which is constitutively active as a transcription activator. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, HNF4 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).

                       10        20        30        40        50        60        70
               ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 9955274   8 CAICGDRSSGKHYGVYSCEGCKGFFKRTVRKDLTYTCRDNKDCLIDKRQRNRCQYCRYQKCLAMGMKREAVQEER 82
Cdd:cd06960  1 CAVCGDRATGKHYGVLSCNGCKGFFRRSVRKNRTYTCRFGGNCVVDKDKRNACRYCRFKKCLEVGMDPEAVQNER 75

DNA-binding domain of the orphan nuclear receptor, nerve growth factor-induced-B; DNA-binding domain (DBD) of the orphan nuclear receptor, nerve growth factor-induced-B (NGFI-B) is composed of two C4-type zinc fingers. Each zinc finger contains a group of four Cys residues which co-ordinates a single zinc atom. NGFI-B interacts with specific DNA sites upstream of the target gene and modulates the rate of transcriptional initiation. NGFI-B is a member of the nuclear-steroid receptor superfamily. NGFI-B is classified as an orphan receptor because no ligand has yet been identified. NGFI-B is an early immediate gene product of embryo development that is rapidly produced in response to a variety of cellular signals including nerve growth factor. It is involved in T-cell-mediated apoptosis, as well as neuronal differentiation and function. NGFI-B regulates transcription by binding to a specific DNA target upstream of its target genes and regulating the rate of transcriptional initiation. NGFI-B binds to the NGFI-B response element (NBRE) 5'-(A/T)AAAGGTCA as a monomer. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, NGFI-B 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 9955274   7 ICAICGDRSSGKHYGVYSCEGCKGFFKRTVRKDLTYTCRDNKDCLIDKRQRNRCQYCRYQKCLAMGMKREAVQ 79
Cdd:cd06969  2 LCAVCGDNAACQHYGVRTCEGCKGFFKRTVQKNAKYVCLANKNCPVDKRRRNRCQYCRFQKCLQVGMVKEVVR 74

DNA-binding domain of the photoreceptor cell-specific nuclear receptor (PNR) like proteins is composed of two C4-type zinc fingers; DNA-binding domain of the photoreceptor cell-specific nuclear receptor (PNR) like proteins is composed of two C4-type zinc fingers. Each zinc finger contains a group of four Cys residues which co-ordinates a single zinc atom. PNR interacts with specific DNA sites upstream of the target gene and modulates the rate of transcriptional initiation. PNR is a member of nuclear receptor superfamily of the ligand-activated transcription factors. PNR is expressed only in the outer layer of retinal photoreceptor cells. It may be involved in the signaling pathway regulating photoreceptor differentiation and/or maintenance. It most likely binds to DNA as a homodimer. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, PNR 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 9955274   8 CAICGDRSSGKHYGVYSCEGCKGFFKRTVRKDLTYTCRDNKDCLIDKRQRNRCQYCRYQKCLAMGMKREAVQEERQ 83
Cdd:cd07164  1 CRVCGDRASGKHYGVPSCDGCRGFFKRSIRRNLAYVCKENGSCVVDVARRNQCQACRFKKCLQVNMNRDAVQHERA 76

c4 zinc finger in nuclear hormone receptors;

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 9955274      7 ICAICGDRSSGKHYGVYSCEGCKGFFKRTVRKDLTYTCRDNKDCLIDKRQRNRCQYCRYQKCLAMGMKRE 76
Cdd:smart00399  1 LCCVCGDHASGFHFGVCSCRACKAFFRRTVNLRYKYRCDRKNNCSINKRYRCRCRACRLKKCLGVGMDPE 70

DNA-binding domain of Retinoid-related orphan receptors (RORs) is composed of two C4-type zinc fingers; DNA-binding domain of Retinoid-related orphan receptors (RORs) is composed of two C4-type zinc fingers. Each zinc finger contains a group of four Cys residues which coordinates a single zinc atom. ROR interacts with specific DNA sites upstream of the target gene and modulates the rate of transcriptional initiation. RORS are key regulators of many physiological processes during embryonic development. RORs bind as monomers to specific ROR response elements (ROREs) consisting of the consensus core motif AGGTCA preceded by a 5-bp A/T-rich sequence. There are three subtypes of retinoid-related orphan receptors (RORs), alpha, beta, and gamma, which differ only in N-terminal sequence and are distributed in distinct tissues. RORalpha plays a key role in the development of the cerebellum particularly in the regulation of the maturation and survival of Purkinje cells. RORbeta expression is largely restricted to several regions of the brain, the retina, and pineal gland. RORgamma is essential for lymph node organogenesis. Recently, it has been suggested that cholesterol or a cholesterol derivative are the natural ligands of RORalpha. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, retinoid-related orphan 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 9955274   8 CAICGDRSSGKHYGVYSCEGCKGFFKRTVRKDLTYTCRDNKDCLIDKRQRNRCQYCRYQKCLAMGMKREAVQEER 82
Cdd:cd06968  8 CKICGDKSSGIHYGVITCEGCKGFFRRSQQNNVSYSCPRQKNCLIDRTNRNRCQHCRLQKCLALGMSRDAVKFGR 82

DNA-binding domain of the photoreceptor cell-specific nuclear receptor (PNR) is composed of two C4-type zinc fingers; DNA-binding domain of the photoreceptor cell-specific nuclear receptor (PNR) is composed of two C4-type zinc fingers. Each zinc finger contains a group of four Cys residues which co-ordinates a single zinc atom. PNR interacts with specific DNA sites upstream of the target gene and modulates the rate of transcriptional initiation. PNR is a member of the nuclear receptor superfamily of the ligand-activated transcription factors. PNR is expressed only in the outer layer of retinal photoreceptor cells. It may be involved in the signaling pathway regulating photoreceptor differentiation and/or maintenance. It most likely binds to DNA as a homodimer. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, PNR 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 9955274   7 ICAICGDRSSGKHYGVYSCEGCKGFFKRTVRKDLTYTCRDNKD-CLIDKRQRNRCQYCRYQKCLAMGMKREAVQEERQ 83
Cdd:cd06970  8 LCRVCGDTSSGKHYGIYACNGCSGFFKRSVRRKLIYRCQAGTGmCPVDKAHRNQCQACRLKKCLQAGMNKDAVQNERQ 85

DNA-binding domain of Tailless (TLX) is composed of two C4-type zinc fingers; DNA-binding domain of Tailless (TLX) is composed of two C4-type zinc fingers. Each zinc finger contains a group of four Cys residues which co-ordinates a single zinc atom. TLX interacts with specific DNA sites upstream of the target gene and modulates the rate of transcriptional initiation. TLX is an orphan receptor that is expressed by neural stem/progenitor cells in the adult brain of the subventricular zone (SVZ) and the dentate gyrus (DG). It plays a key role in neural development by promoting cell cycle progression and preventing apoptosis in the developing brain. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, TLX 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 9955274   8 CAICGDRSSGKHYGVYSCEGCKGFFKRTVRKDLTYTCRDNK--DCLIDKRQRNRCQYCRYQKCLAMGMKREAVQEER 82
Cdd:cd07163  9 CKVCGDRSSGKHYGIYACDGCSGFFKRSIRRNRQYVCKSKGqgGCPVDKTHRNQCRACRLKKCFEVGMNKDAVQHER 85

DNA-binding domain of the photoreceptor cell-specific nuclear receptor (PNR) like is composed of two C4-type zinc fingers; The DNA-binding domain of the photoreceptor cell-specific nuclear receptor (PNR) nuclear receptor-like family is composed of two C4-type zinc fingers. Each zinc finger contains a group of four Cys residues which coordinates a single zinc atom. PNR interacts with specific DNA sites upstream of the target gene and modulates the rate of transcriptional initiation. This family includes nuclear receptor Tailless (TLX), photoreceptor cell-specific nuclear receptor (PNR) and related receptors. TLX is an orphan receptor that plays a key role in neural development by regulating cell cycle progression and exit of neural stem cells in the developing brain. PNR is expressed only in the outer layer of retinal photoreceptor cells. It may be involved in the signaling pathway regulating photoreceptor differentiation and/or maintenance. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, PNR-like receptors have 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 9955274   8 CAICGDRSSGKHYGVYSCEGCKGFFKRTVRKDLTYTC-RDNKDCLIDKRQRNRCQYCRYQKCLAMGMKREAVQEER 82
Cdd:cd06957  1 CKVCGDKSYGKHYGVYCCDGCSCFFKRSVRKGIIYTCiAGNGNCVVDKARRNWCPFCRLQKCFAVGMNRAAVQEER 76

DNA-binding domain of estrogen related receptors (ERR) is composed of two C4-type zinc fingers; DNA-binding domain of estrogen related receptors (ERRs) is composed of two C4-type zinc fingers. Each zinc finger contains a group of four Cys residues which coordinates a single zinc atom. ERR interacts with the palindromic inverted repeat, 5'GGTCAnnnTGACC-3', upstream of the target gene and modulates the rate of transcriptional initiation. The estrogen receptor-related receptors (ERRs) are transcriptional regulators, which are closely related to the estrogen receptor (ER) family. Although ERRs lack the ability to bind to estrogen and are so-called orphan receptors, they share target genes, co-regulators and promoters with the estrogen receptor (ER) family. By targeting the same set of genes, ERRs seem to interfere with the classic ER-mediated estrogen response in various ways. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, ERR has 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 9955274   5 KHICAICGDRSSGKHYGVYSCEGCKGFFKRTVRKDLTYTCRDNKDCLIDKRQRNRCQYCRYQKCLAMGMKREAVQEERQR 84
Cdd:cd07170  4 KRLCLVCGDIASGYHYGVASCEACKAFFKRTIQGNIEYSCPATNECEITKRRRKSCQACRFMKCLKVGMLKEGVRLDRVR 83

               .
gi 9955274  85 G 85
Cdd:cd07170 84 G 84

DNA-binding domain of estrogen receptor (ER) and estrogen related receptors (ERR) is composed of two C4-type zinc fingers; DNA-binding domains of estrogen receptor (ER) and estrogen related receptors (ERR) are composed of two C4-type zinc fingers. Each zinc finger contains a group of four Cys residues which co-ordinates a single zinc atom. ER and ERR interact with the palindromic inverted repeat, 5'GGTCAnnnTGACC-3', upstream of the target gene and modulate the rate of transcriptional initiation. ERR and ER are closely related and share sequence similarity, target genes, co-regulators and promoters. While ER is activated by endogenous estrogen, ERR lacks the ability to bind to estrogen. Estrogen receptor mediates the biological effects of hormone estrogen by the binding of the receptor dimer to estrogen response element of target genes. However, ERRs seem to interfere with the classic ER-mediated estrogen responsive signaling by targeting the same set of genes. ERRs and ERs exhibit the common modular structure with other nuclear receptors. They have a central highly conserved DNA binding domain (DBD), a non-conserved N-terminal domain, a flexible hinge and a C-terminal ligand binding domain (LBD).

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               ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 9955274   8 CAICGDRSSGKHYGVYSCEGCKGFFKRTVRKDLTYTCRDNKDCLIDKRQRNRCQYCRYQKCLAMGMKREAVQEER 82
Cdd:cd07155  1 CLVCGDIASGYHYGVASCEACKAFFKRTIQGNLGYSCPSTSECEVDKKRRKSCQACRLQKCLKVGMLKEGVRLDR 75

DNA-binding domain of REV-ERB receptor-like is composed of two C4-type zinc fingers; DNA-binding domain of REV-ERB receptor- like is composed of two C4-type zinc fingers. Each zinc finger contains a group of four Cys residues which coordinates a single zinc atom. This domain interacts with specific DNA sites upstream of the target gene and modulates the rate of transcriptional initiation. REV-ERB receptors 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. REV-ERB receptors bind as a monomer to a (A/G)GGTCA half-site with a 5' AT-rich extension or as a homodimer to a direct repeat 2 element (AGGTCA sequence with a 2-bp spacer), indicating functional diversity. When bound to the DNA, they recruit corepressors (NcoR/histone deacetylase 3) to the promoter, resulting in repression of the target genes. The porphyrin heme has been demonstrated to function as a ligand for REV-ERB receptor. 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 9955274   7 ICAICGDRSSGKHYGVYSCEGCKGFFKRTVRKDLTY-TCRDNKDCLIDKRQRNRCQYCRYQKCLAMGMKREAVQEER 82
Cdd:cd07166  5 LCKVCGDKASGFHYGVHACEGCKGFFRRSIQQKIQYrKCTKNETCSIMRINRNRCQYCRFKKCLAVGMSRDAVRFGR 81

The DNA-binding domain of vitamin D receptors (VDR) like nuclear receptor family is composed of two C4-type zinc fingers; The DNA-binding domain of vitamin D receptors (VDR) like nuclear receptor family is composed of two C4-type zinc fingers. Each zinc finger contains a group of four Cys residues which co-ordinates a single zinc atom. This domain interacts with specific DNA site upstream of the target gene and modulates the rate of transcriptional initiation. This family includes three types of nuclear receptors: vitamin D receptors (VDR), constitutive androstane receptor (CAR) and pregnane X receptor (PXR). VDR regulates calcium metabolism, cellular proliferation and differentiation. PXR and CAR function as sensors of toxic byproducts of cell metabolism and of exogenous chemicals, to facilitate their elimination. The DNA binding activity is regulated by their corresponding ligands. VDR is activated by Vitamin D; CAR and PXR respond to a diverse array of chemically distinct ligands, including many endogenous compounds and clinical drugs. Like other nuclear receptors, xenobiotic receptors have 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 9955274   8 CAICGDRSSGKHYGVYSCEGCKGFFKRTVRKDLTYTCRDNKDCLIDKRQRNRCQYCRYQKCLAMGMKREAV 78
Cdd:cd07156  1 CGVCGDRATGYHFNAMTCEGCKGFFRRSMKRKARFTCPFNGDCEITKDNRRHCQACRLKKCLDIGMKKEMI 71

DNA-binding domain of Liver X receptors (LXRs) family is composed of two C4-type zinc fingers; DNA-binding domain of Liver X receptors (LXRs) family is composed of two C4-type zinc fingers. Each zinc finger contains a group of four Cys residues which co-ordinates a single zinc atom. LXR interacts with specific DNA sites upstream of the target gene and modulates the rate of transcriptional initiation. LXR operates as cholesterol sensor which protects cells from cholesterol overload by stimulating reverse cholesterol transport from peripheral tissues to the liver and its excretion in the bile. Oxidized cholesterol derivatives or oxysterols were identified as specific ligands for LXRs. LXR functions as a heterodimer with the retinoid X receptor (RXR) which may be activated by either LXR agonist or 9-cis retinoic acid, a specific RXR ligand. The LXR/RXR complex binds to a liver X receptor response element (LXRE) in the promoter region of target genes. The ideal LXRE sequence is a direct repeat-4 (DR-4) DNA fragment consisting of two AGGTCA hexameric half-sites separated by a 4-nucleotide spacer. LXR has typical NR modular structure with a central well conserved DNA binding domain (DBD), a variable N-terminal domain, a flexible hinge and the ligand binding domain (LBD) at the C-terminal.

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                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 9955274    7 ICAICGDRSSGKHYGVYSCEGCKGFFKRTVRKDLTYTCRDNKDCLIDKRQRNRCQYCRYQKCLAMGMKREAVQEERQ 83
Cdd:cd07160  20 VCSVCGDKASGFHYNVLSCEGCKGFFRRSVIKGAQYVCKNGGKCQMDMYMRRKCQECRLRKCREAGMREQCVLSEEQ 96

The DNA-binding domain of Ecdysone receptor (EcR) like nuclear receptor family is composed of two C4-type zinc fingers; The DNA-binding domain of Ecdysone receptor (EcR) like nuclear receptor family is composed of two C4-type zinc fingers. Each zinc finger contains a group of four Cys residues which co-ordinates a single zinc atom. EcR interacts with specific DNA sites upstream of the target gene and modulates the rate of transcriptional initiation. This family includes three types of nuclear receptors: Ecdysone receptor (EcR), Liver X receptor (LXR) and Farnesoid X receptor (FXR). The DNA binding activity is regulated by their corresponding ligands. The ligands for EcR are ecdysteroids; LXR is regulated by oxidized cholesterol derivatives or oxysterols; and bile acids control FXR's activities. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, EcR-like receptors have 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 9955274   8 CAICGDRSSGKHYGVYSCEGCKGFFKRTVRKDLTYTCRDNKDCLIDKRQRNRCQYCRYQKCLAMGMKREAV 78
Cdd:cd06959  2 CVVCGDKASGFHYGVLSCEGCKGFFRRSVTKGAVYACKFGNKCEMDMYMRRKCQECRLRKCKAAGMRPDCL 72

DNA-binding domain of constitutive androstane receptor (CAR) is composed of two C4-type zinc fingers; DNA-binding domain (DBD) of constitutive androstane receptor (CAR) is composed of two C4-type zinc fingers. Each zinc finger contains a group of four Cys residues which co-ordinates a single zinc atom. CAR DBD interacts with CAR response element, a perfect repeat of two AGTTCA motifs with a 4 bp spacer upstream of the target gene, and modulates the rate of transcriptional initiation. The constitutive androstane receptor (CAR) is a ligand-regulated transcription factor that responds to a diverse array of chemically distinct ligands, including many endogenous compounds and clinical drugs. It functions as a heterodimer with RXR. The CAR/RXR heterodimer binds many common response elements in the promoter regions of a diverse set of target genes involved in the metabolism, transport, and ultimately, elimination of these molecules from the body. CAR is a closest mammalian relative of PXR and is activated by some of the same ligands as PXR and regulates a subset of common genes. The sequence homology and functional similarity suggests that the CAR gene arose from a duplication of an ancestral PXR gene. Like other nuclear receptors, CAR has a central well conserved DNA binding domain, a variable N-terminal domain, a flexible hinge and a C-terminal ligand binding domain.

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               ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 9955274   7 ICAICGDRSSGKHYGVYSCEGCKGFFKRTVRKDLTYTCRDNKDCLIDKRQRNRCQYCRYQKCLAMGMKREAVQEERQR 84
Cdd:cd06966  2 ICGVCGDKALGYNFNAITCESCKAFFRRNALKNKEFKCPFNESCEINVVTRRFCQKCRLDKCFAIGMKKEWIMSEEDK 79

DNA-binding domain of Farnesoid X receptor (FXR) family is composed of two C4-type zinc fingers; DNA-binding domain of Farnesoid X receptor (FXR) family is composed of two C4-type zinc fingers. Each zinc finger contains a group of four Cys residues which co-ordinates a single zinc atom. FXR interacts with specific DNA sites upstream of the target gene and modulates the rate of transcriptional initiation. FXR is a member of the nuclear receptor family of ligand activated transcription factors. Bile acids are endogenous ligands for FXRs. Upon binding of a ligand, FXR binds to FXR response element (FXRE), which is an inverted repeat of TGACCT spaced by one nucleotide, either as a monomer or as a heterodimer with retinoid X receptor (RXR), to regulate the expression of various genes involved in bile acid, lipid, and glucose metabolism. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, FXR 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 9955274   7 ICAICGDRSSGKHYGVYSCEGCKGFFKRTVRKDLTYTCRDNKDCLIDKRQRNRCQYCRYQKCLAMGMKREAVQEERQ 83
Cdd:cd06962  3 LCVVCGDKASGYHYNALTCEGCKGFFRRSITKNAVYKCKNGGNCEMDMYMRRKCQECRLRKCKEMGMLAECLLTEIQ 79

The first DNA-binding domain (DBD) of the 2DBD nuclear receptors is composed of two C4-type zinc fingers; The first DNA-binding domain (DBD) of the 2DBD nuclear receptors(NRs) is composed of two C4-type zinc fingers. Each zinc finger contains a group of four Cys residues which co-ordinates a single zinc atom. NRs interact with specific DNA sites upstream of the target gene and modulate the rate of transcriptional initiation. Theses proteins contain two DBDs in tandem, probably resulted from an ancient recombination event. The 2DBD-NRs are found only in flatworm species, mollusks and arthropods. Their biological function is unknown.

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gi 9955274   8 CAICGDRSSGKHYGVYSCEGCKGFFKRTVRKDL--TYTCRDNKDCLIDKRQRNRCQYCRYQKCLAMGMK 74
Cdd:cd07157  3 CQVCGEPAAGFHHGAYVCEACKKFFMRSSNAISftISECPNGGKCIIDKKNRTKCQACRYRKCLNVGMS 71

DNA-binding domain of androgen receptor (AR) is composed of two C4-type zinc fingers; DNA-binding domain of androgen receptor (AR) is composed of two C4-type zinc fingers. Each zinc finger contains a group of four Cys residues which co-ordinates a single zinc atom. To regulate gene expression, AR interacts with a palindrome of the core sequence 5'-TGTTCT-3' with a 3-bp spacer. It also binds to the direct repeat 5'-TGTTCT-3' hexamer in some androgen controlled genes. AR is activated by the androgenic hormones, testosterone or dihydrotestosterone, which are responsible for primary and for secondary male characteristics, respectively. The primary mechanism of action of ARs is by direct regulation of gene transcription. The binding of androgen results in a conformational change in the androgen receptor which causes its transport from the cytosol into the cell nucleus, and dimerization. The receptor dimer binds to a hormone response element of AR regulated genes and modulates their expression. Another mode of action of androgen receptor is independent of their interactions with DNA. The receptor interacts directly with signal transduction proteins in the cytoplasm, causing rapid changes in cell function, such as ion transport. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, AR 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 9955274   5 KHICAICGDRSSGKHYGVYSCEGCKGFFKRTVRKDLTYTCRDNKDCLIDKRQRNRCQYCRYQKCLAMGM 73
Cdd:cd07173  3 QKTCLICGDEASGCHYGALTCGSCKVFFKRAAEGKQKYLCASRNDCTIDKFRRKNCPSCRLRKCFEAGM 71