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 71990114 151 CRVCGDSRAGRHYGTIACNGCKGFFRRSIWEQRDYVCRFGGKCLVVQEYRNRCRACRLRKCFTVGMDARAVQSERD 226
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 71990114 151 CRVCGDSRAGRHYGTIACNGCKGFFRRSIWEQRDYVCRFGGKCLVVQEYRNRCRACRLRKCFTVGMDARAVQSERD 226
Cdd:cd06960   1 CAVCGDRATGKHYGVLSCNGCKGFFRRSVRKNRTYTCRFGGNCVVDKDKRNACRYCRFKKCLEVGMDPEAVQNERD 76

c4 zinc finger in nuclear hormone receptors;

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 71990114    150 KCRVCGDSRAGRHYGTIACNGCKGFFRRSIWEQRDYVCRFGGKCLVVQEYRNRCRACRLRKCFTVGMD 217
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 71990114   151 CRVCGDSRAGRHYGTIACNGCKGFFRRSIWEQRDYVCRFGGKCLVVQEYRNRCRACRLRKCFTVGMD 217
Cdd:pfam00105   2 CKVCGDKASGYHYGVLTCEGCKGFFRRSIQKNIVYTCKFNKDCVIDKRNRNRCQYCRLKKCLEVGMS 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 71990114 151 CRVCGDSRAGRHYGTIACNGCKGFFRRSIWEQRDYVCRFGGKCLVVQEYRNRCRACRLRKCFTVGMDARAVQSERD 226
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 71990114 151 CRVCGDSRAGRHYGTIACNGCKGFFRRSIWEQRDYVCRFGGKCLVVQEYRNRCRACRLRKCFTVGMDARAVQ 222
Cdd:cd06916   1 CAVCGDKASGYHYGVLTCEGCKGFFRRSVRRNLEYTCPAGGNCVIDKRNRNRCQACRLKKCLAVGMRKEAVR 72

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 71990114 374 EDVHIAWCRSFVLCIDYAKIMKDYQELSPTDQFTLLRNRVISVNWLCHTYKTFKAGCDGVALVNGSWYPRDKELQKqldp 453
Cdd:cd06157   1 ELLCELATRDLLLIVEWAKSIPGFRELPLEDQIVLLKSFWLELLVLDLAYRSYKNGLSLLLAPNGGHTDDDKEDEM---- 76

                        90       100       110       120       130       140       150       160
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 71990114 454 gCNHYFRILSEHLMEdLVIPMREMDMDEGEFVILKALILFRAHRRLSEEGRAHIKRVRDKYIEALYQHVQHQHRHfssvQ 533
Cdd:cd06157  77 -KLLLKGELIRLLFE-FVNPLRALKLDDEEYALLKAIVLFSPDRKESLEDRKIVEELQERLLEALQDYLRKNYPE----E 150

                       170
                ....*....|....*...
gi 71990114 534 TSMRISKILLLLPSIEHL 551
Cdd:cd06157 151 APSRFAKLLLLLPSLRKL 168

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 71990114 151 CRVCGDSRAGRHYGTIACNGCKGFFRRSIWEQRDYVCRF--GGKCLVVQEYRNRCRACRLRKCFTVGMDARAVQSER 225
Cdd:cd07163   9 CKVCGDRSSGKHYGIYACDGCSGFFKRSIRRNRQYVCKSkgQGGCPVDKTHRNQCRACRLKKCFEVGMNKDAVQHER 85

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).

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 71990114 147 TGLKCRVCGDSRAGRHYGTIACNGCKGFFRRSIWEQRDYVCRFG-GKCLVVQEYRNRCRACRLRKCFTVGMDARAVQSER 225
Cdd:cd06970   5 PGLLCRVCGDTSSGKHYGIYACNGCSGFFKRSVRRKLIYRCQAGtGMCPVDKAHRNQCQACRLKKCLQAGMNKDAVQNER 84

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).

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 71990114 151 CRVCGDSRAGRHYGTIACNGCKGFFRRSIWEQRDYVCRFGGKCLVVQEYRNRCRACRLRKCFTVGMDARAVQSER 225
Cdd:cd06967   6 CVVCGDKASGRHYGAVSCEGCKGFFKRSIRKNLGYSCRGSKDCVINKHHRNRCQYCRLQKCLAMGMKSDSVQCER 80

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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 71990114 151 CRVCGDSRAGRHYGTIACNGCKGFFRRSIWEQRDYVCRFGGKCLVVQEYRNRCRACRLRKCFTVGMDARAVQSER 225
Cdd:cd06961   2 CVVCGDKATGYHYRCITCEGCKGFFRRTVQKKLSYSCKGEGKCEIDKVTRNQCQECRFKKCIAVGMAKDLVLDDR 76

Ligand-binding domain of nuclear hormone receptor; This all helical domain is involved in binding the hormone in these receptors.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 71990114   372 TLEDVHIAWCRSFVLCIDYAKIMKDYQELSPTDQFTLLRN---RVISVNWLCHTYKTFKAGCDGVALVNGSWYPRDKELQ 448
Cdd:pfam00104  12 TKEELCELWERDLLLVAEWAKHFPEFQELPLEDQMALLKSfwlEWLRLEKAARSAKLRRKKILGEDVLMISDDDAMKFVE 91

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 71990114   449 KQLDPGCNH------YFRILSEHLMEDLVIPMREMDMDEGEFVILKALILFR-AHRRLSEEGRAHIKRVRDKYIEALYQH 521
Cdd:pfam00104  92 DDSSWCTNYdleqllFFLPFFNSYFFELVKPLRELNPDDEELAYLLAQLLFDyAGDGLSGEILEIVEKLQEKLANELHDY 171

                         170       180       190
                  ....*....|....*....|....*....|.
gi 71990114   522 VQHQHrhfssvqtSMRISKILLLLPSIEHLS 552
Cdd:pfam00104 172 YVNKY--------SGRLAKLLKILPSLRKIS 194

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 71990114 151 CRVCGDSRAGRHYGTIACNGCKGFFRRSIWEQRDYVCRFGGKCLVVQEYRNRCRACRLRKCFTVGMDARAVQSER 225
Cdd:cd06956   3 CAICGDRASGKHYGVYSCEGCKGFFKRTVRKDLTYTCRDNKDCLIDKRQRNRCQYCRYQKCLAMGMKREAVQEER 77

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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 71990114 150 KCRVCGDSRAGRHYGTIACNGCKGFFRRSIWEQRDYVCRFGGKCLVVQEYRNRCRACRLRKCFTVGMDARAVQSER 225
Cdd:cd07171   5 FCAVCSDYASGYHYGVWSCEGCKAFFKRSIQGHNDYICPATNQCTIDKNRRKSCQACRLRKCYEVGMMKGGIRRER 80

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).

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 71990114 151 CRVCGDSRAGRHYGTIACNGCKGFFRRSIWEQRDY-VCRFGGKCLVVQEYRNRCRACRLRKCFTVGMDARAVQSERDKHK 229
Cdd:cd07166   6 CKVCGDKASGFHYGVHACEGCKGFFRRSIQQKIQYrKCTKNETCSIMRINRNRCQYCRFKKCLAVGMSRDAVRFGRIPKR 85

                ....
gi 71990114 230 KNPK 233
Cdd:cd07166  86 EKAR 89

DNA-binding domain of Germ cell nuclear factor (GCNF) F1 is composed of two C4-type zinc fingers; DNA-binding domain of Germ cell nuclear factor (GCNF) F1 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. GCNF is a transcription factor expressed in post-meiotic stages of developing male germ cells. In vitro, GCNF has the ability to bind to direct repeat elements of 5'-AGGTCA.AGGTCA-3', as well as to an extended half-site sequence 5'-TCA.AGGTCA-3'. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, GCNF 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 71990114 151 CRVCGDSRAGRHYGTIACNGCKGFFRRSIWEQRDYVCRFGGKCLVVQEYRNRCRACRLRKCFTVGMDARAVQSERDKHKK 230
Cdd:cd07169   9 CLICGDRATGLHYGIISCEGCKGFFKRSICNKRVYRCSRDKNCVMSRKQRNRCQYCRLLKCLQMGMNRKAIREDGMPGGR 88

                .
gi 71990114 231 N 231
Cdd:cd07169  89 N 89

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).

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 71990114 151 CRVCGDSRAGRHYGTIACNGCKGFFRRSIWEQRDYVCRFGGKCLVVQEYRNRCRACRLRKCFTVGMDARAVQ 222
Cdd:cd06969   3 CAVCGDNAACQHYGVRTCEGCKGFFKRTVQKNAKYVCLANKNCPVDKRRRNRCQYCRFQKCLQVGMVKEVVR 74

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 71990114 151 CRVCGDSRAGRHYGTIACNGCKGFFRRSIWEQRDYVCRFGGKCLVVQEYRNRCRACRLRKCFTVGMDARAVQS 223
Cdd:cd06958   1 CVVCGDKSSGKHYGQFTCEGCKSFFKRSVRRNLTYTCRGNRNCPIDQHHRNQCQYCRLKKCLKVGMRREAVQR 73

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.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 71990114 151 CRVCGDSRAGRHYGTIACNGCKGFFRRSIWEQRDYVCRFGGKCLVVQEYRNRCRACRLRKCFTVGMDARAVQSERDKHKK 230
Cdd:cd06966   3 CGVCGDKALGYNFNAITCESCKAFFRRNALKNKEFKCPFNESCEINVVTRRFCQKCRLDKCFAIGMKKEWIMSEEDKSEK 82

                ....*....
gi 71990114 231 NPKDSNNEG 239
Cdd:cd06966  83 RQKIEENRA 91

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).

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 71990114 151 CRVCGDSRAGRHYGTIACNGCKGFFRRSIWEQRDYVCRFGGKCLVVQEYRNRCRACRLRKCFTVGMDARAVQSER 225
Cdd:cd06968   8 CKICGDKSSGIHYGVITCEGCKGFFRRSQQNNVSYSCPRQKNCLIDRTNRNRCQHCRLQKCLALGMSRDAVKFGR 82

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 71990114 151 CRVCGDSRAGRHYGTIACNGCKGFFRRSIWEQRDYVCRFGGKCLVVQEYRNRCRACRLRKCFTVGMDARAVQSER 225
Cdd:cd07155   1 CLVCGDIASGYHYGVASCEACKAFFKRTIQGNLGYSCPSTSECEVDKKRRKSCQACRLQKCLKVGMLKEGVRLDR 75

DNA-binding domain of vitamin D receptors (VDR) is composed of two C4-type zinc fingers; DNA-binding domain of vitamin D receptors (VDR) is composed of two C4-type zinc fingers. Each zinc finger contains a group of four Cys residues which coordinates a single zinc atom. VDR interacts with a VDR response element, a direct repeat of GGTTCA DNA site with 3 bp spacer upstream of the target gene, and modulates the rate of transcriptional initiation. VDR is a member of the nuclear receptor (NR) superfamily that functions as classical endocrine receptors. VDR controls a wide range of biological activities including calcium metabolism, cell proliferation and differentiation, and immunomodulation. VDR is a high-affinity receptor for the biologically most active Vitamin D metabolite, 1alpha,25-dihydroxyvitamin D3 (1alpha,25(OH)2D3). The binding of the ligand to the receptor induces a conformational change of the ligand binding domain (LBD) with consequent dissociation of corepressors. Upon ligand binding, VDR forms a heterodimer with the retinoid X receptor (RXR) that binds to vitamin D response elements (VDREs), recruits coactivators. This leads to the expression of a large number of genes. Approximately 200 human genes are considered to be primary targets of VDR and even more genes are regulated indirectly. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, VDR 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 71990114 151 CRVCGDSRAGRHYGTIACNGCKGFFRRSIWEQRDYVCRFGGKCLVVQEYRNRCRACRLRKCFTVGMDARAVQSERDKHKK 230
Cdd:cd06955   9 CGVCGDRATGFHFNAMTCEGCKGFFRRSMKRKALFTCPFNGDCRITKDNRRHCQACRLKRCVDIGMMKEFILTDEEVQRK 88

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).

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 71990114 151 CRVCGDSRAGRHYGTIACNGCKGFFRRSIWEQRDYVCRFGGKCLVVQEYRNRCRACRLRKCFTVGMDARAVQSER----- 225
Cdd:cd07170   7 CLVCGDIASGYHYGVASCEACKAFFKRTIQGNIEYSCPATNECEITKRRRKSCQACRFMKCLKVGMLKEGVRLDRvrggr 86

                        90
                ....*....|..
gi 71990114 226 DKHKKNPkDSNN 237
Cdd:cd07170  87 QKYKRRI-DAEN 97

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.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 71990114 150 KCRVCGDSRAGRHYGTIACNGCKGFFRRSIWEQR--DYVCRFGGKCLVVQEYRNRCRACRLRKCFTVGM 216
Cdd:cd07157   2 TCQVCGEPAAGFHHGAYVCEACKKFFMRSSNAISftISECPNGGKCIIDKKNRTKCQACRYRKCLNVGM 70

The DNA binding domain of GR_like nuclear receptors is composed of two C4-type zinc fingers; The DNA binding domain of GR_like 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 specific DNA sites upstream of the target gene and modulates the rate of transcriptional initiation. This family of NRs includes four types of nuclear hormone receptors: glucocorticoid receptor (GR), mineralocorticoid receptor (MR), progesterone receptor (PR), and androgen receptor (AR). The receptors bind to common DNA elements containing a partial palindrome of the core sequence 5'-TGTTCT-3' with a 3bp spacer. These four receptors regulate some of the most fundamental physiological functions such as the stress response, metabolism, electrolyte homeostasis, immune function, growth, development, and reproduction. The NRs in this family have high sequence homology and share similar functional mechanisms. The dominant mechanism of function is by direct DNA binding and transcriptional regulation of target genes . The GR, MR, PR, and AR exhibit same modular structure. 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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 71990114 151 CRVCGDSRAGRHYGTIACNGCKGFFRRSIWEQRDYVCRFGGKCLVVQEYRNRCRACRLRKCFTVGM 216
Cdd:cd06963   1 CLICGDEASGCHYGVLTCGSCKVFFKRAAEGQHNYLCAGRNDCIIDKIRRKNCPACRLRKCYQAGM 66

Ligand-binding domain of nuclear receptor family 2; Ligand-binding domain (LBD) of nuclear receptor (NR) family 2: This is one of the major subfamily of nuclear receptors, including some well known nuclear receptors such as glucocorticoid receptor (GR), mineralocorticoid receptor (MR), estrogen receptor (ER), progesterone receptor (PR), and androgen receptor (AR), other related receptors. 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 non-conserved hinge and a C-terminal ligand binding domain (LBD).

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 71990114 381 CRSFVLCIDYAKIMKDYQELSPTDQFTLLRNRvisvnW-----LCHTYktfkagcDGVALVNGSwYPRDKELQKQLDPGC 455
Cdd:cd06930   9 DRVLFKTVDWAKNLPAFRNLPLDDQLTLLQNS-----WaelllLGLAQ-------RSVHFELSE-LLLPSPLLVILTERE 75

                        90       100       110       120       130       140       150       160
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 71990114 456 NHyfRILSEHL--MEDLVIPMREMDMDEGEFVILKALILFRA-HRRLSEegRAHIKRVRDKYIEALYQHVQHQHRhfssv 532
Cdd:cd06930  76 AL--LGLAELVqrLQELLSKLRSLQLDPKEYACLKAIVLFNPdLPGLKN--QQQVEELQEKAQQALQEYIRKRYP----- 146

                       170
                ....*....|....*....
gi 71990114 533 QTSMRISKILLLLPSIEHL 551
Cdd:cd06930 147 QQPARFAKLLLRLPELRSI 165

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 71990114 388 IDYAKIMKDYQELSPTDQFTLLR---NRVISVNwLCHTYKTFKagcDGVALVNGSWYPRDKELQKQLDPgcnhYF-RILS 463
Cdd:cd06943  47 VEWAKRIPHFSELPLDDQVILLRagwNELLIAA-FAHRSIAVK---DGILLATGLHLHRNSAHQAGVGA----IFdRILT 118

                        90       100       110       120       130       140       150       160
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 71990114 464 EhlmedLVIPMREMDMDEGEFVILKALILFRAH-RRLSEegRAHIKRVRDKYIEALYQHVQHQHrhfsSVQTSmRISKIL 542
Cdd:cd06943 119 E-----LVVKMRDLKMDRTELGCLRAIILFNPDvKGLKS--RQEVESLREKVYASLEEYCRQKH----PEQPG-RFAKLL 186

                       170
                ....*....|....*..
gi 71990114 543 LLLP---SI-----EHL 551
Cdd:cd06943 187 LRLPalrSIglkclEHL 203

The ligand binding domain of estrogen receptor-related nuclear receptors; The ligand binding domain of estrogen receptor-related receptors (ERRs): The family of estrogen receptor-related receptors (ERRs), a subfamily of nuclear receptors, is closely related to the estrogen receptor (ER) family, but it lacks the ability to bind estrogen. ERRs can interfere with the classic ER-mediated estrogen signaling pathway, positively or negatively. ERRs share target genes, co-regulators and promoters with the estrogen receptor (ER) family. There are three subtypes of ERRs: alpha, beta and gamma. ERRs bind at least two types of DNA sequence, the estrogen response element and another site, originally characterized as SF-1 (steroidogenic factor 1) response element. 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 flexible hinge and a C-terminal ligand binding domain (LBD).

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 71990114 366 ALERLTTLEDVHIawcRSFVLCIDYAKIMKDYQELSPTDQFTLLRNRVISVNWLCHTYKTFKagCDGvALVNGSWYPRDK 445
Cdd:cd06946  25 DIKALTTLSDLAD---RELVVIIGWAKHIPGFSSLSLNDQMSLLQSAWMEILTLGVVFRSLP--FNG-ELVFAEDFILDE 98

                        90       100       110       120       130       140       150       160
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 71990114 446 ELQKqldpgCNHYFRILSeHLMEdLVIPMREMDMDEGEFVILKALILFRAHRRLSEEGRAhIKRVRDKYIEALYQHVQHQ 525
Cdd:cd06946  99 ELAR-----EAGLLELYS-ACLQ-LVRRLQRLRLEKEEYVLLKALALANSDSVHIEDVEA-VRQLRDALLEALSDYEAGR 170

                       170       180       190
                ....*....|....*....|....*....|....*.
gi 71990114 526 HrhfsSVQTSMRISKILLLLPSiehLSQQEDDNVQF 561
Cdd:cd06946 171 H----PGEAPRRAGQLLLTLPL---LRQTDGKARRF 199

Ligand-binding domain of nuclear receptor family 1; Ligand-binding domain (LBD) of nuclear receptor (NR) family 1: This is one of the major subfamily of nuclear receptors, including thyroid receptor, retinoid acid receptor, ecdysone receptor, farnesoid X receptor, vitamin D receptor, and other related receptors. 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).

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 71990114 387 CIDYAKIMKDYQELSPTDQFTLLRN---RVISVNWlCHTYktfkaGCDGVALVNGSWYPRDKELQKQLdpgcnhYFRILS 463
Cdd:cd06929  18 VVEFAKRIPGFRELSQEDQIALLKGgcfEILLLRS-ATLY-----DPEKNSLTFGDGKGNSRDVLLNG------GFGEFI 85

                        90       100       110       120       130       140       150       160
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 71990114 464 EHLMEdLVIPMREMDMDEGEFVILKALILFRAHRRlSEEGRAHIKRVRDKYIEALYQHVQHQHRhfssvQTSMRISKILL 543
Cdd:cd06929  86 EPLFE-FAEKMNKLQLDDNEYALLTAIVLFSPDRP-GLQDVDTVEKLQERLLEALQRYLKVNHP-----DAPQMFAKLLK 158

                ...
gi 71990114 544 LLP 546
Cdd:cd06929 159 KLT 161

Ligand binding domain of Estrogen receptor, which are activated by the hormone 17beta-estradiol (estrogen); The ligand binding domain (LBD) of Estrogen receptor (ER): Estrogen receptor, a member of nuclear receptor superfamily, is activated by the hormone estrogen. Estrogen regulates many physiological processes including reproduction, bone integrity, cardiovascular health, and behavior. The main mechanism of action of the estrogen receptor is as a transcription factor by binding to the estrogen response element of target genes upon activation by estrogen and then recruiting coactivator proteins which are responsible for the transcription of target genes. Additionally some ERs may associate with other membrane proteins and can be rapidly activated by exposure of cells to estrogen. 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 flexible hinge and a C-terminal ligand binding domain (LBD). The C-terminal LBD also contains AF-2 activation motif, the dimerization motif, and part of the nuclear localization region. Estrogen receptor has been linked to aging, cancer, obesity and other diseases.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 71990114 475 REMDMDEGEFVILKALILFRA--HRRLSE--EGRAHIKRVRDKYIEALYQHVqhQHRHFSSVQTSMRISKILLLLPSIEH 550
Cdd:cd06949 127 RELQLQREEYVCLKAIILLNSsvYTFLLEslESRRQVQRLLDKITDALVHAC--SKRGLSLQQQSRRLAQLLLILSHIRH 204

                ..
gi 71990114 551 LS 552
Cdd:cd06949 205 VS 206

Ligand binding domain of chicken ovalbumin upstream promoter transcription factors, a member of the nuclear receptor family; The ligand binding domain of chicken ovalbumin upstream promoter transcription factors (COUP-TFs): 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. In mammals two isoforms named COUP-TFI and COUP-TFII have been identified. Both genes show an exceptional homology and overlapping expression patterns, suggesting that they may serve redundant functions. Although COUP-TF was originally characterized as a transcriptional activator of the chicken ovalbumin gene, 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 cons erved 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 71990114 466 LMEDLVIPMREMDMDEGEFVILKALILFRAHRR-LSEEgrAHIKRVRDKYIEALYQHVQHQHRHfssvQTSmRISKILLL 544
Cdd:cd06948 117 IFQEQVEKLKALHVDSAEFSCLKAIVLFTSDACgLSDP--AHIESLQEKSQCALEEYVRTQYPN----QPT-RFGKLLLR 189

                        90       100
                ....*....|....*....|
gi 71990114 545 LPSIEHLSQQEDDNVQFLAL 564
Cdd:cd06948 190 LPSLRTVSSSVIEQLFFVRL 209