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 1972305589  21 CHICSDVATGRHYGAIACNGCKGFFRRTVRRNYEYHCRFESKCEIDKHNRAVCRYCRFMKCISSGMRDDQVQSERD 96
Cdd:cd06960     1 CAVCGDRATGKHYGVLSCNGCKGFFRRSVRKNRTYTCRFGGNCVVDKDKRNACRYCRFKKCLEVGMDPEAVQNERD 76

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 1972305589  21 CHICSDVATGRHYGAIACNGCKGFFRRTVRRNYEYHCRFESKCEIDKHNRAVCRYCRFMKCISSGMRDDQVQSERD 96
Cdd:cd06960     1 CAVCGDRATGKHYGVLSCNGCKGFFRRSVRKNRTYTCRFGGNCVVDKDKRNACRYCRFKKCLEVGMDPEAVQNERD 76

c4 zinc finger in nuclear hormone receptors;

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1972305589   20 ICHICSDVATGRHYGAIACNGCKGFFRRTVRRNYEYHCRFESKCEIDKHNRAVCRYCRFMKCISSGMR 87
Cdd:smart00399   1 LCCVCGDHASGFHFGVCSCRACKAFFRRTVNLRYKYRCDRKNNCSINKRYRCRCRACRLKKCLGVGMD 68

Zinc finger, C4 type (two domains); In nearly all cases, this is the DNA binding domain of a nuclear hormone receptor. The alignment contains two Zinc finger domains that are too dissimilar to be aligned with each other.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1972305589  20 ICHICSDVATGRHYGAIACNGCKGFFRRTVRRNYEYHCRFESKCEIDKHNRAVCRYCRFMKCISSGMR 87
Cdd:pfam00105   1 LCKVCGDKASGYHYGVLTCEGCKGFFRRSIQKNIVYTCKFNKDCVIDKRNRNRCQYCRLKKCLEVGMS 68

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 1972305589  21 CHICSDVATGRHYGAIACNGCKGFFRRTVRRNYEYHCRFESKCEIDKHNRAVCRYCRFMKCISSGMRDDQVQSERD 96
Cdd:cd06960     1 CAVCGDRATGKHYGVLSCNGCKGFFRRSVRKNRTYTCRFGGNCVVDKDKRNACRYCRFKKCLEVGMDPEAVQNERD 76

DNA-binding domain of nuclear receptors is composed of two C4-type zinc fingers; DNA-binding domain of nuclear receptors 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. It interacts with a specific DNA site upstream of the target gene and modulates the rate of transcriptional initiation. Nuclear receptors form a superfamily of ligand-activated transcription regulators, which regulate various physiological functions, from development, reproduction, to homeostasis and metabolism in animals (metazoans). The family contains not only receptors for known ligands but also orphan receptors for which ligands do not exist or have not been identified. NRs share a common structural organization with a central well conserved DNA binding domain (DBD), a variable N-terminal domain, a flexible hinge and a C-terminal ligand binding domain (LBD). Most nuclear receptors bind as homodimers or heterodimers to their target sites, which consist of two hexameric half-sites. Specificity is determined by the half-site sequence, the relative orientation of the half-sites and the number of spacer nucleotides between the half-sites. However, a growing number of nuclear receptors have been reported to bind to DNA as monomers.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1972305589  21 CHICSDVATGRHYGAIACNGCKGFFRRTVRRNYEYHCRFESKCEIDKHNRAVCRYCRFMKCISSGMRDDQVQ 92
Cdd:cd06916     1 CAVCGDKASGYHYGVLTCEGCKGFFRRSVRRNLEYTCPAGGNCVIDKRNRNRCQACRLKKCLAVGMRKEAVR 72

DNA-binding domain of thyroid hormone receptors (TRs) is composed of two C4-type zinc fingers; DNA-binding domain of thyroid hormone receptors (TRs) 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. TR interacts with the thyroid response element, which is a DNA site with direct repeats of the consensus sequence 5'-AGGTCA-3' separated by one to five base pairs, upstream of target genes and modulates the rate of transcriptional initiation. Thyroid hormone receptor (TR) mediates 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).

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1972305589  21 CHICSDVATGRHYGAIACNGCKGFFRRTVRRNYEYHCRFESKCEIDKHNRAVCRYCRFMKCISSGMRDDQVQSERDVIGK 100
Cdd:cd06961     2 CVVCGDKATGYHYRCITCEGCKGFFRRTVQKKLSYSCKGEGKCEIDKVTRNQCQECRFKKCIAVGMAKDLVLDDRKRGAK 81

                  .
gi 1972305589 101 R 101
Cdd:cd06961    82 R 82

Zinc finger, C4 type (two domains); In nearly all cases, this is the DNA binding domain of a nuclear hormone receptor. The alignment contains two Zinc finger domains that are too dissimilar to be aligned with each other.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1972305589  20 ICHICSDVATGRHYGAIACNGCKGFFRRTVRRNYEYHCRFESKCEIDKHNRAVCRYCRFMKCISSGMR 87
Cdd:pfam00105   1 LCKVCGDKASGYHYGVLTCEGCKGFFRRSIQKNIVYTCKFNKDCVIDKRNRNRCQYCRLKKCLEVGMS 68

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 1972305589  19 SICHICSDVATGRHYGAIACNGCKGFFRRTVRRNYEYHCRFESKCEIDKHNRAVCRYCRFMKCISSGMRDDQVQSER 95
Cdd:cd06956     1 HICAICGDRASGKHYGVYSCEGCKGFFKRTVRKDLTYTCRDNKDCLIDKRQRNRCQYCRYQKCLAMGMKREAVQEER 77

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).

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1972305589  21 CHICSDVATGRHYGAIACNGCKGFFRRTVRRNYEYHCRFESKCEIDKHNRAVCRYCRFMKCISSGMRDDQVQSERDV 97
Cdd:cd07164     1 CRVCGDRASGKHYGVPSCDGCRGFFKRSIRRNLAYVCKENGSCVVDVARRNQCQACRFKKCLQVNMNRDAVQHERAP 77

The DNA-binding domain of Lrh-1 like nuclear receptor family like is composed of two C4-type zinc fingers; The DNA-binding domain of Lrh-1 like nuclear receptor family like 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 sites upstream of the target gene and modulates the rate of transcriptional initiation. This nuclear receptor family includes at least three subgroups of receptors that function in embryo development and differentiation, and other processes. FTZ-F1 interacts with the cis-acting DNA motif of ftz gene, which is required at several stages of development. Particularly, FTZ-F1 regulated genes are strongly linked to steroid biosynthesis and sex-determination; LRH-1 is a regulator of bile-acid homeostasis, steroidogenesis, reverse cholesterol transport and the initial stages of embryonic development; SF-1 is an essential regulator of endocrine development and function and is considered a master regulator of reproduction; SF-1 functions cooperatively with other transcription factors to modulate gene expression. Phospholipids have been identified as potential ligand for LRH-1 and steroidogenic factor-1 (SF-1). However, the ligand for FTZ-F1 has not yet been identified. Most nuclear receptors function as homodimer or heterodimers. However, LRH-1 and SF-1 bind to DNA as monomers. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, receptors in this family 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).

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1972305589  21 CHICSDVATGRHYGAIACNGCKGFFRRTVRRNYEYHCRFESKCEIDKHNRAVCRYCRFMKCISSGMRDDQVQSERdVIGK 100
Cdd:cd07167     1 CPVCGDKVSGYHYGLLTCESCKGFFKRTVQNKKRYTCIENQNCQIDKTQRKRCPYCRFQKCLSVGMKLEAVRADR-MRGG 79

                          90
                  ....*....|....*.
gi 1972305589 101 REKKDNMktYCQDPTP 116
Cdd:cd07167    80 RNKFGPM--YKRDRAL 93

DNA-binding domain of chicken ovalbumin upstream promoter transcription factors (COUP-TFs) is composed of two C4-type zinc fingers; DNA-binding domain of chicken ovalbumin upstream promoter transcription factors (COUP-TFs) 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. COUP-TFs are orphan members of the steroid/thyroid hormone receptor superfamily. They are expressed in many tissues and are involved in the regulation of several important biological processes, such as neurogenesis, organogenesis, cell fate determination, and metabolic homeostasis. COUP-TFs homodimerize or heterodimerize with retinoid X receptor (RXR) and a few other nuclear receptors and bind to a variety of response elements that are composed of imperfect AGGTCA direct or inverted repeats with various spacings. COUP-TFs are generally considered to be repressors of transcription for other nuclear hormone receptors such as retinoic acid receptor (RAR), thyroid hormone receptor (TR), vitamin D receptor (VDR), peroxisome proliferator activated receptor (PPAR), and hepatocyte nuclear factor 4 (HNF4). Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, COUP-TFs 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).

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1972305589  21 CHICSDVATGRHYGAIACNGCKGFFRRTVRRNYEYHCRFESKCEIDKHNRAVCRYCRFMKCISSGMRDDQVQS 93
Cdd:cd06958     1 CVVCGDKSSGKHYGQFTCEGCKSFFKRSVRRNLTYTCRGNRNCPIDQHHRNQCQYCRLKKCLKVGMRREAVQR 73

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).

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1972305589 179 NDVLKSMHSQLLLVIEWAKTLPEFKQLSGADQAVLLKNFAGQHVTLCVAYRSV---GANDALKLLNDLYIPRASKTTPHL 255
Cdd:cd06157     1 ELLCELATRDLLLIVEWAKSIPGFRELPLEDQIVLLKSFWLELLVLDLAYRSYkngLSLLLAPNGGHTDDDKEDEMKLLL 80

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1972305589 256 KEYVDgfylrdceKVMDQLVEPMRFLKLDNKEFVALKACVLFNPvAPGLSNHAVNLVLNARRKIFAAFEKYVRVNKPLE- 334
Cdd:cd06157    81 KGELI--------RLLFEFVNPLRALKLDDEEYALLKAIVLFSP-DRKESLEDRKIVEELQERLLEALQDYLRKNYPEEa 151

                  ....*..
gi 1972305589 335 TTRVGDL 341
Cdd:cd06157   152 PSRFAKL 158

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).

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1972305589  21 CHICSDVATGRHYGAIACNGCKGFFRRTVRRNYEYHCRFESK--CEIDKHNRAVCRYCRFMKCISSGMRDDQVQSER 95
Cdd:cd07163     9 CKVCGDRSSGKHYGIYACDGCSGFFKRSIRRNRQYVCKSKGQggCPVDKTHRNQCRACRLKKCFEVGMNKDAVQHER 85

The ligand binding domain of the retinoid X receptor and Ultraspiracle, members of nuclear receptor superfamily; The ligand binding domain of the retinoid X receptor (RXR) and Ultraspiracle (USP): This family includes two evolutionary related nuclear receptors: retinoid X receptor (RXR) and Ultraspiracle (USP). RXR is a nuclear receptor in mammalian and USP is its counterpart in invertebrates. The native ligand of retinoid X receptor is 9-cis retinoic acid (RA). RXR functions as a DNA binding partner by forming heterodimers with other nuclear receptors including CAR, FXR, LXR, PPAR, PXR, RAR, TR, and VDR. RXRs can play different roles in these heterodimers. It 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. Ultraspiracle (USP) plays similar roles as DNA binding partner of other nuclear rec eptors in invertebrates. USP has no known high-affinity ligand and is thought to be a silent component in the heterodimeric complex with partner receptors. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, RXR and USP 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).

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1972305589 126 PVEdeydQLLESLLKSEMTIQSLRDTVITQTGNVeyttksknrlshtdrtatlNDVLKSMHSQLLLVIEWAKTLPEFKQL 205
Cdd:cd06943     3 PIE----RILEAELAVEPKSEAVAMVPPEYRDPV-------------------SNICQAADKQLFQLVEWAKRIPHFSEL 59

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1972305589 206 SGADQAVLLKnfAGQHVTLC--VAYRSVGANDALKLLNDLYIPRASKTTPHLKEYVDgfylrdceKVMDQLVEPMRFLKL 283
Cdd:cd06943    60 PLDDQVILLR--AGWNELLIaaFAHRSIAVKDGILLATGLHLHRNSAHQAGVGAIFD--------RILTELVVKMRDLKM 129

                         170       180       190       200       210
                  ....*....|....*....|....*....|....*....|....*....|....*...
gi 1972305589 284 DNKEFVALKACVLFNPVAPGLSNhaVNLVLNARRKIFAAFEKYVRVNKPLETTRVGDL 341
Cdd:cd06943   130 DRTELGCLRAIILFNPDVKGLKS--RQEVESLREKVYASLEEYCRQKHPEQPGRFAKL 185

DNA-binding domain of retinoic acid receptor (RAR) is composed of two C4-type zinc fingers; DNA-binding domain of retinoic acid receptor (RAR) 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. RAR interacts with specific DNA sites upstream of the target gene and modulates the rate of transcriptional initiation. RARs mediate the biological effect of retinoids, including both natural 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. RAR function as a heterodimer with retinoic X receptor by binding to specific RAR response elements (RAREs), which are composed of two direct repeats of the consensus sequence 5'-AGGTCA-3' separated by one to five base pair and found in the promoter regions of retinoid target genes. 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).

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1972305589  21 CHICSDVATGRHYGAIACNGCKGFFRRTVRRNYEYHCRFESKCEIDKHNRAVCRYCRFMKCISSGMRDDQVQSERD 96
Cdd:cd06964     7 CFVCQDKSSGYHYGVSACEGCKGFFRRSIQKNMVYTCHRDKNCIINKVTRNRCQYCRLQKCFEVGMSKESVRNDRN 82

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).

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1972305589  21 CHICSDVATGRHYGAIACNGCKGFFRRTVRRNYEYHCRFESKCEIDKHNRAVCRYCRFMKCISSGMRDDQV 91
Cdd:cd07156     1 CGVCGDRATGYHFNAMTCEGCKGFFRRSMKRKARFTCPFNGDCEITKDNRRHCQACRLKKCLDIGMKKEMI 71

DNA-binding domain of pregnane X receptor (PXRs) is composed of two C4-type zinc fingers; DNA-binding domain (DBD)of pregnane X receptor (PXR) 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. PXR DBD interacts with the PXR 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 pregnane X receptor (PXR) is a ligand-regulated transcription factor that responds to a diverse array of chemically distinct ligands, including many endogenous compounds and clinical drugs. PXR functions as a heterodimer with retinoic X receptor-alpha (RXRa) and binds to a variety of promoter regions of a diverse set of target genes involved in the metabolism, transport, and ultimately, elimination of these molecules from the body. Like other nuclear receptors, PXR has a central well conserved DNA-binding domain, a variable N-terminal domain, a flexible hinge and a C-terminal ligand binding domain.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1972305589  20 ICHICSDVATGRHYGAIACNGCKGFFRRTVRRNYEYHCRFESKCEIDKHNRAVCRYCRFMKCISSGMRDDQVQSERDVIG 99
Cdd:cd07162     1 ICRVCGDRATGYHFNAMTCEGCKGFFRRAMKRNARLCCPFQKGCVITKSNRRQCQACRLRKCLSIGMKKELIMSDEAVEK 80

                  ..
gi 1972305589 100 KR 101
Cdd:cd07162    81 RR 82

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).

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 1972305589  21 CHICSDVATGRHYGAIACNGCKGFFRRTVRRNYEYHCRFESKCEIDKHNRAVCRYCRFMKCISSGMRDD 89
Cdd:cd06959     2 CVVCGDKASGFHYGVLSCEGCKGFFRRSVTKGAVYACKFGNKCEMDMYMRRKCQECRLRKCKAAGMRPD 70

The DNA-binding domain of the photoreceptor cell-specific nuclear receptor (PNR) nuclear receptor-like family; 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).

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1972305589  21 CHICSDVATGRHYGAIACNGCKGFFRRTVRRNYEYHCRFES-KCEIDKHNRAVCRYCRFMKCISSGMRDDQVQ 92
Cdd:cd07154     1 CKVCGDRSSGKHYGVYACDGCSGFFKRSIRRNLLYTCKAGNgSCVVDKARRNQCQACRLKKCLEVSMNKDAVQ 73

DNA-binding domain of estrogen receptors (ER) is composed of two C4-type zinc fingers; DNA-binding domain of estrogen receptors (ER) is composed of two C4-type zinc fingers. Each zinc finger contains a group of four Cys residues which coordinates a single zinc atom. ER interacts with specific DNA sites upstream of the target gene and modulates the rate of transcriptional initiation. Estrogen receptor is a transcription regulator that mediates the biological effects of hormone estrogen. The binding of estrogen to the receptor triggers the dimerization and the binding of the receptor dimer to estrogen response element, which is a palindromic inverted repeat: 5'GGTCAnnnTGACC-3', of target genes. Through ER, estrogen regulates development, reproduction and homeostasis. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, ER 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).

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1972305589  16 KDNSICHICSDVATGRHYGAIACNGCKGFFRRTVRRNYEYHCRFESKCEIDKHNRAVCRYCRFMKCISSGMRDDQVQSER 95
Cdd:cd07171     1 KDTHFCAVCSDYASGYHYGVWSCEGCKAFFKRSIQGHNDYICPATNQCTIDKNRRKSCQACRLRKCYEVGMMKGGIRRER 80

DNA-binding domain of peroxisome proliferator-activated receptors (PPAR) is composed of two C4-type zinc fingers; DNA-binding domain of peroxisome proliferator-activated receptors (PPAR) 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. PPAR interacts with specific DNA sites upstream of the target gene and modulates the rate of transcriptional initiation. 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 elements, which are composed of two direct repeats of the consensus sequence 5'-AGGTCA-3' separated by one to five base pair located upstream of the peroxisome proliferator responsive genes, and interacts with co-activators. 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 and a C-terminal ligand binding domain (LBD).

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 1972305589  21 CHICSDVATGRHYGAIACNGCKGFFRRTVRRNYEYHcRFESKCEIDKHNRAVCRYCRFMKCISSGMRDDQVQSER 95
Cdd:cd06965     2 CRVCGDKASGFHYGVHACEGCKGFFRRTIRLKLVYK-PCDLSCKIHKKSRNKCQYCRFQKCLNVGMSHNAIRFGR 75

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).

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 1972305589  21 CHICSDVATGRHYGAIACNGCKGFFRRTVRRNYEYHCRFESKCEIDKHNRAVCRYCRFMKCISSGMRDDQVQSER 95
Cdd:cd07155     1 CLVCGDIASGYHYGVASCEACKAFFKRTIQGNLGYSCPSTSECEVDKKRRKSCQACRLQKCLKVGMLKEGVRLDR 75

The second DNA-binding domain (DBD) of the 2DBD nuclear receptor is composed of two C4-type zinc fingers; The second DNA-binding domain (DBD) of the 2DBD nuclear receptor (NR) 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. The proteins contain two DBDs in tandem, probably resulting from an ancient recombination event. The 2DBD-NRs are found only in flatworm species, mollusks and arthropods. Their biological function is unknown.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1972305589  21 CHICSDVATGRHYGAIACNGCKGFFRRTVRRNYEYHCRFESKCEIDKHNRAVCRYCRFMKCISSGM 86
Cdd:cd07179     1 CRVCGGKSSGFHFGALTCEGCKGFFRRTELSSNSYVCPGGQNCAITPATRNACKSCRFRRCLAVGM 66

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).

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1972305589  21 CHICSDVATGRHYGAIACNGCKGFFRRTVRRNYEYHC-RFESKCEIDKHNRAVCRYCRFMKCISSGMRDDQVQSER 95
Cdd:cd06957     1 CKVCGDKSYGKHYGVYCCDGCSCFFKRSVRKGIIYTCiAGNGNCVVDKARRNWCPFCRLQKCFAVGMNRAAVQEER 76

DNA-binding domain of glucocorticoid receptor (GR) is composed of two C4-type zinc fingers; DNA-binding domains of glucocorticoid receptor (GR) and progesterone receptor (PR) are composed of two C4-type zinc fingers. Each zinc finger contains a group of four Cys residues which co-ordinate a single zinc atom. The DBD from both receptors interact with the same hormone response element (HRE), which is an imperfect palindrome GGTACAnnnTGTTCT, upstream of target genes and modulates the rate of transcriptional initiation. GR is a transcriptional regulator that mediates the biological effects of glucocorticoids and PR regulates genes controlled by progesterone. GR is expressed in almost every cell in the body and regulates genes controlling a wide variety of processes including the development, metabolism, and immune response of the organism. PR functions in a variety of biological processes including development of the mammary gland, regulating cell cycle progression, protein processing, and metabolism. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, GR and PR 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).

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1972305589  20 ICHICSDVATGRHYGAIACNGCKGFFRRTVRRNYEYHCRFESKCEIDKHNRAVCRYCRFMKCISSGM 86
Cdd:cd07172     4 ICLVCSDEASGCHYGVLTCGSCKVFFKRAVEGQHNYLCAGRNDCIIDKIRRKNCPACRLRKCLQAGM 70

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).

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1972305589  21 CHICSDVATGRHYGAIACNGCKGFFRRTVRRNYEYHCRFESKCEIDKHNRAVCRYCRFMKCISSGM 86
Cdd:cd07173     6 CLICGDEASGCHYGALTCGSCKVFFKRAAEGKQKYLCASRNDCTIDKFRRKNCPSCRLRKCFEAGM 71

The ligand binding domain of the liver receptor homolog-1, a member of nuclear receptor superfamily,; The ligand binding domain (LBD) of the liver receptor homolog-1 (LRH-1): LRH-1 belongs to nuclear hormone receptor superfamily, and is expressed mainly in the liver, intestine, exocrine pancreas, and ovary. Most nuclear receptors function as homodimer or heterodimers. However, LRH-1 binds DNA as a monomer, and is a regulator of bile-acid homeostasis, steroidogenesis, reverse cholesterol transport and the initial stages of embryonic development. Recently, phospholipids have been identified as potential ligand for LRH-1 and steroidogenic factor-1 (SF-1). Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, LRH-1 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 1972305589 133 QLLESLLKSEmtiqslRDTVITQTGNVEYTTKSKNRLSHTDRTATLNDVLKSMHSQLLLVIEWAKTLPEFKQLSGADQAV 212
Cdd:cd07069     3 HLILELLKCE------PDEPQVQAKIMAYLQQEQANRSKHEKLSTFGLMCKMADQTLFSIVEWARSSIFFRELKVDDQMK 76

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1972305589 213 LLKNFAGQHVTLCVAYRSV--GANDALKLLNDLYIPRASKTTPhlkeyvDGFYLRDCEKVMDQLVEPMRFLKLDNKEFVA 290
Cdd:cd07069    77 LLQNCWSELLILDHIYRQVvhGKEGSIFLVTGQQVDYSIIASQ------AGATLNNLMSHAQELVAKLRSLQFDQREFVC 150

                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1972305589 291 LKACVLFNPVAPGLSNhaVNLVLNARRKIFAAFEKYVRVNKPLETTRVGDLtFFILTPLSVLSKSISEDIMFTKVSGVAR 370
Cdd:cd07069   151 LKFLVLFSLDVKNLEN--FQLVEGVQEQVNAALLDYTMCNYPQQTEKFGQL-LLRLPEIRAISMQAEEYLYYKHLNGDVP 227