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 1622871068  52 DDRAEQRTCLICGDRATGLHYGIISCEGCKGFFKRSICNKRVYRCSRDKNCVMSRKQRNRCQYCRLLKCLQMGMNRKAIR 131
Cdd:cd07169     1 DDRAEQRTCLICGDRATGLHYGIISCEGCKGFFKRSICNKRVYRCSRDKNCVMSRKQRNRCQYCRLLKCLQMGMNRKAIR 80

                          90
                  ....*....|
gi 1622871068 132 EDGMPGGRNK 141
Cdd:cd07169    81 EDGMPGGRNK 90

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 1622871068  52 DDRAEQRTCLICGDRATGLHYGIISCEGCKGFFKRSICNKRVYRCSRDKNCVMSRKQRNRCQYCRLLKCLQMGMNRKAIR 131
Cdd:cd07169     1 DDRAEQRTCLICGDRATGLHYGIISCEGCKGFFKRSICNKRVYRCSRDKNCVMSRKQRNRCQYCRLLKCLQMGMNRKAIR 80

                          90
                  ....*....|
gi 1622871068 132 EDGMPGGRNK 141
Cdd:cd07169    81 EDGMPGGRNK 90

c4 zinc finger in nuclear hormone receptors;

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622871068   59 TCLICGDRATGLHYGIISCEGCKGFFKRSICNKRVYRCSRDKNCVMSRKQRNRCQYCRLLKCLQMGMNRK 128
Cdd:smart00399   1 LCCVCGDHASGFHFGVCSCRACKAFFRRTVNLRYKYRCDRKNNCSINKRYRCRCRACRLKKCLGVGMDPE 70

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 1622871068 286 LCRLADELLFRQIAWIKKLPFFCELSIKDYTCLLSSTWQELILL----SSLTVYSKQIFGELADVTAKYSPSDEELHRFS 361
Cdd:pfam00104  16 LCELWERDLLLVAEWAKHFPEFQELPLEDQMALLKSFWLEWLRLekaaRSAKLRRKKILGEDVLMISDDDAMKFVEDDSS 95

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622871068 362 DEGMEVIERLIY-----------LYHKFHQLKVSNEEYACMKAINFLNQDIRGLTSaSQLEQLNKRYWYICQDFTEYKYT 430
Cdd:pfam00104  96 WCTNYDLEQLLFflpffnsyffeLVKPLRELNPDDEELAYLLAQLLFDYAGDGLSG-EILEIVEKLQEKLANELHDYYVN 174

                         170
                  ....*....|....*..
gi 1622871068 431 HQPNRFPDLMMCLPEIR 447
Cdd:pfam00104 175 KYSGRLAKLLKILPSLR 191

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 1622871068  52 DDRAEQRTCLICGDRATGLHYGIISCEGCKGFFKRSICNKRVYRCSRDKNCVMSRKQRNRCQYCRLLKCLQMGMNRKAIR 131
Cdd:cd07169     1 DDRAEQRTCLICGDRATGLHYGIISCEGCKGFFKRSICNKRVYRCSRDKNCVMSRKQRNRCQYCRLLKCLQMGMNRKAIR 80

                          90
                  ....*....|
gi 1622871068 132 EDGMPGGRNK 141
Cdd:cd07169    81 EDGMPGGRNK 90

DNA-binding domain of ecdysone-induced DHR4 orphan nuclear receptor is composed of two C4-type zinc fingers; DNA-binding domain of ecdysone-induced DHR4 orphan nuclear receptor 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. Ecdysone-induced orphan receptor DHR4 is a member of the nuclear receptor family. DHR4 is expressed during the early Drosophila larval development and is induced by ecdysone. DHR4 coordinates growth and maturation in Drosophila by mediating endocrine response to the attainment of proper body size during larval development. Mutations in DHR4 result in shorter larval development which translates into smaller and lighter flies. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, DHR4 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 1622871068  52 DDRAEQRTCLICGDRATGLHYGIISCEGCKGFFKRSICNKRVYRCSRDKNCVMSRKQRNRCQYCRLLKCLQMGMNRKAIR 131
Cdd:cd07168     1 DEDESPKLCSICEDKATGLHYGIITCEGCKGFFKRTVQNKRVYTCVGDGRCEITKAQRNRCQYCRFRKCIRKGMMLAAVR 80

                          90
                  ....*....|
gi 1622871068 132 EDGMPGGRNK 141
Cdd:cd07168    81 EDRMPGGRNS 90

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 1622871068  60 CLICGDRATGLHYGIISCEGCKGFFKRSICNKRVYRCSRDKNCVMSRKQRNRCQYCRLLKCLQMGMNRKAIREDGMPGGR 139
Cdd:cd07167     1 CPVCGDKVSGYHYGLLTCESCKGFFKRTVQNKKRYTCIENQNCQIDKTQRKRCPYCRFQKCLSVGMKLEAVRADRMRGGR 80

                  ..
gi 1622871068 140 NK 141
Cdd:cd07167    81 NK 82

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 1622871068 285 LLCRLADELLFRQIAWIKKLPFFCELSIKDYTCLLSSTWQELILLSSLTVYSKQIFGELADVTAKYSPSDEELHRFSDEG 364
Cdd:cd06157     2 LLCELATRDLLLIVEWAKSIPGFRELPLEDQIVLLKSFWLELLVLDLAYRSYKNGLSLLLAPNGGHTDDDKEDEMKLLLK 81

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622871068 365 MEVIERLIYLYHKFHQLKVSNEEYACMKAINFLNQDI-RGLTSASQLEQLNKRYWYICQDFTEYKY-THQPNRFPDLMMC 442
Cdd:cd06157    82 GELIRLLFEFVNPLRALKLDDEEYALLKAIVLFSPDRkESLEDRKIVEELQERLLEALQDYLRKNYpEEAPSRFAKLLLL 161

                  ....*..
gi 1622871068 443 LPEIRYI 449
Cdd:cd06157   162 LPSLRKL 168

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 1622871068  60 CLICGDRATGLHYGIISCEGCKGFFKRSICNKRVYRCSRDKNCVMSRKQRNRCQYCRLLKCLQMGMNRKAIRED 133
Cdd:cd06960     1 CAVCGDRATGKHYGVLSCNGCKGFFRRSVRKNRTYTCRFGGNCVVDKDKRNACRYCRFKKCLEVGMDPEAVQNE 74

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        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622871068  58 RTCLICGDRATGLHYGIISCEGCKGFFKRSICNKRVYRCSRDKNCVMSRKQRNRCQYCRLLKCLQMGMNRKAIREDgmpg 137
Cdd:cd06964     5 KPCFVCQDKSSGYHYGVSACEGCKGFFRRSIQKNMVYTCHRDKNCIINKVTRNRCQYCRLQKCFEVGMSKESVRND---- 80

                  ....
gi 1622871068 138 gRNK 141
Cdd:cd06964    81 -RNK 83

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 1622871068  60 CLICGDRATGLHYGIISCEGCKGFFKRSICNKRVYRCSRDKNCVMSRKQRNRCQYCRLLKCLQMGMNRKAIRED 133
Cdd:cd06956     3 CAICGDRASGKHYGVYSCEGCKGFFKRTVRKDLTYTCRDNKDCLIDKRQRNRCQYCRYQKCLAMGMKREAVQEE 76

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 1622871068  59 TCLICGDRATGLHYGIISCEGCKGFFKRSICNKRVYRCSRDKNCVMSRKQRNRCQYCRLLKCLQMGMNRKAIR 131
Cdd:cd06969     2 LCAVCGDNAACQHYGVRTCEGCKGFFKRTVQKNAKYVCLANKNCPVDKRRRNRCQYCRFQKCLQVGMVKEVVR 74

Ligand binding domain of hormone receptors;

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622871068  290 ADELLFRQIAWIKKLPFFCELSIKDYTCLLSSTWQELILLSSLTVYSKQIFGELADVTAKYSPSDEELHRFSDEGMEVIE 369
Cdd:smart00430   1 AERQLLLTVEWAKSFPGFRELSLEDQIVLLKSFWFELLLLELAYRSVKLKKELLLAPDGTYIRPDAVLELRKLFSPFLDR 80

                           90       100       110       120       130       140       150       160
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622871068  370 RLIYLYHKFHQLKVSNEEYACMKAINFLNQDIRGLTSASQ--LEQLNKRYWYICQDFTEYKY-THQPNRFPDLMMCLPEI 446
Cdd:smart00430  81 ILSELVKPLRELKLDDEEYALLKAIVLFNPAVPGLSEEGKeiVEKLQEKYANALHDYYLKNYpMNYPGRFAKLLLILPEL 160

                   ...
gi 1622871068  447 RYI 449
Cdd:smart00430 161 RKI 163

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
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1622871068  60 CLICGDRATGLHYGIISCEGCKGFFKRSICNKRVYR-CSRDKNCVMSRKQRNRCQYCRLLKCLQMGMNRKAIR 131
Cdd:cd07166     6 CKVCGDKASGFHYGVHACEGCKGFFRRSIQQKIQYRkCTKNETCSIMRINRNRCQYCRFKKCLAVGMSRDAVR 78

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 1622871068  60 CLICGDRATGLHYGIISCEGCKGFFKRSICNKRVY-RCsrDKNCVMSRKQRNRCQYCRLLKCLQMGMNRKAIREDGMP 136
Cdd:cd06965     2 CRVCGDKASGFHYGVHACEGCKGFFRRTIRLKLVYkPC--DLSCKIHKKSRNKCQYCRFQKCLNVGMSHNAIRFGRMP 77

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 1622871068  60 CLICGDRATGLHYGIISCEGCKGFFKRSICNKRVYRC-SRDKNCVMSRKQRNRCQYCRLLKCLQMGMNRKAIR 131
Cdd:cd07154     1 CKVCGDRSSGKHYGVYACDGCSGFFKRSIRRNLLYTCkAGNGSCVVDKARRNQCQACRLKKCLEVSMNKDAVQ 73

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        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1622871068  60 CLICGDRATGLHYGIISCEGCKGFFKRSICNKRVYRCSRDKNCVMSRKQRNRCQYCRLLKCLQMGMNRKAIR 131
Cdd:cd07179     1 CRVCGGKSSGFHFGALTCEGCKGFFRRTELSSNSYVCPGGQNCAITPATRNACKSCRFRRCLAVGMSKTGSR 72

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        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622871068  60 CLICGDRATGLHYGIISCEGCKGFFKRSICNKRVYRC-SRDK-NCVMSRKQRNRCQYCRLLKCLQMGMNRKAIREDGMPg 137
Cdd:cd07163     9 CKVCGDRSSGKHYGIYACDGCSGFFKRSIRRNRQYVCkSKGQgGCPVDKTHRNQCRACRLKKCFEVGMNKDAVQHERGP- 87

                  ....*.
gi 1622871068 138 gRNKSI 143
Cdd:cd07163    88 -RNSTL 92

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 1622871068  60 CLICGDRATGLHYGIISCEGCKGFFKRSICNKRVYRCSRDKNCVMSRKQRNRCQYCRLLKCLQMGMNRKAIRED 133
Cdd:cd07155     1 CLVCGDIASGYHYGVASCEACKAFFKRTIQGNLGYSCPSTSECEVDKKRRKSCQACRLQKCLKVGMLKEGVRLD 74

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 1622871068  55 AEQRTCLICGDRATGLHYGIISCEGCKGFFKRSICNKRVYRCSRDKNCVMSRKQRNRCQYCRLLKCLQMGMNRKAIRED 133
Cdd:cd07171     1 KDTHFCAVCSDYASGYHYGVWSCEGCKAFFKRSIQGHNDYICPATNQCTIDKNRRKSCQACRLRKCYEVGMMKGGIRRE 79

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 1622871068  60 CLICGDRATGLHYGIISCEGCKGFFKRSICNKRVYRCSRDKNCVMSRKQRNRCQYCRLLKCLQMGM 125
Cdd:cd06959     2 CVVCGDKASGFHYGVLSCEGCKGFFRRSVTKGAVYACKFGNKCEMDMYMRRKCQECRLRKCKAAGM 67

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).

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622871068 286 LCRLADELLFRQIAWIKKLPFFCELSIKDYTCLLSSTWQELILLSSL---TVYSKQIFgeLAdvtakyspSDEELHRFSD 362
Cdd:cd06943    35 ICQAADKQLFQLVEWAKRIPHFSELPLDDQVILLRAGWNELLIAAFAhrsIAVKDGIL--LA--------TGLHLHRNSA 104

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622871068 363 EGMEV---IERLIY-LYHKFHQLKVSNEEYACMKAINFLNQDIRGLTSASQLEQLNKRYWYICQDFTEYKYTHQPNRFPD 438
Cdd:cd06943   105 HQAGVgaiFDRILTeLVVKMRDLKMDRTELGCLRAIILFNPDVKGLKSRQEVESLREKVYASLEEYCRQKHPEQPGRFAK 184

                         170
                  ....*....|....
gi 1622871068 439 LMMCLPEIRYIAGK 452
Cdd:cd06943   185 LLLRLPALRSIGLK 198

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

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1622871068  60 CLICGDRATGLHYGIISCEGCKGFFKRSICNKRVYRCSRDK-NCVMSRKQRNRCQYCRLLKCLQMGMNRKAIREDGMP 136
Cdd:cd06957     1 CKVCGDKSYGKHYGVYCCDGCSCFFKRSVRKGIIYTCIAGNgNCVVDKARRNWCPFCRLQKCFAVGMNRAAVQEERGP 78

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).

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622871068  53 DRAEQRTCLICGDRATGLHYGIISCEGCKGFFKRSICNKRVYRCSRDKNCVMSRKQRNRCQYCRLLKCLQMGMNRKAIRE 132
Cdd:cd06955     2 DRNVPRICGVCGDRATGFHFNAMTCEGCKGFFRRSMKRKALFTCPFNGDCRITKDNRRHCQACRLKRCVDIGMMKEFILT 81

                  .
gi 1622871068 133 D 133
Cdd:cd06955    82 D 82

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).

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622871068 286 LCRLADELLFRQIAWIKKLPFFCELSIKDYTCLLSSTWQELILLSSLTVYSK-QIFGELADVTAKYSP-SDEELHRFSDE 363
Cdd:cd06948    35 ICELAARLLFSAVEWARNIPFFPDLQVTDQVALLRLSWSELFVLNAAQCCMPlHVAPLLAAAGLHASPmSADRVVAFMDH 114

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622871068 364 gMEVIERLIylyHKFHQLKVSNEEYACMKAINFLNQDIRGLTSASQLEQLNKRYWYICQDFTEYKYTHQPNRFPDLMMCL 443
Cdd:cd06948   115 -IRIFQEQV---EKLKALHVDSAEFSCLKAIVLFTSDACGLSDPAHIESLQEKSQCALEEYVRTQYPNQPTRFGKLLLRL 190

                         170
                  ....*....|....*...
gi 1622871068 444 PEIRYIAGKMVnvplEQL 461
Cdd:cd06948   191 PSLRTVSSSVI----EQL 204

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
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1622871068  58 RTCLICGDRATGLHYGIISCEGCKGFFKRSICNKRVYRCSRDKNCVMSRKQRNRCQYCRLLKCLQMGMNRKAI 130
Cdd:cd06966     1 KICGVCGDKALGYNFNAITCESCKAFFRRNALKNKEFKCPFNESCEINVVTRRFCQKCRLDKCFAIGMKKEWI 73

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).

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622871068  60 CLICGDRATGLHYGIISCEGCKGFFKRSICNKRVYRCSRDKNCVMSRKQRNRCQYCRLLKCLQMGMNRKA 129
Cdd:cd06963     1 CLICGDEASGCHYGVLTCGSCKVFFKRAAEGQHNYLCAGRNDCIIDKIRRKNCPACRLRKCYQAGMTLGA 70

The ligand binding domain of Tailless-like proteins, orphan nuclear receptors; The ligand binding domain of the photoreceptor cell-specific nuclear receptor (PNR) like family: This family includes photoreceptor cell-specific nuclear receptor (PNR), Tailless (TLX), and related receptors. 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. 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, TLX and PNR 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 1622871068 286 LCRLADELLFRQIAWIKKLPFFCELSIKDYTCLLSSTWQELILLS----SLTVYSKQIF---GELADVTAKYSPSDEELH 358
Cdd:cd06950    31 VCESAARLLFMAVKWAKSIPAFSTLPFRDQLILLEESWSELFLLGaaqwSLPLDSCPLLavpGLSPDNTEAERTFLSEVR 110

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1622871068 359 RFSDegmevierliyLYHKFHQLKVSNEEYACMKAINFLNQDIRGLTSASQLEQLnkrywyicQD-----FTEYKYTH-- 431
Cdd:cd06950   111 ALQE-----------TLSRFRQLRVDATEFACLKAIVLFKPETRGLKDPAQVEAL--------QDqaqlmLNKHIRTRyp 171

                         170
                  ....*....|....*....
gi 1622871068 432 -QPNRFPDLMMCLPEIRYI 449
Cdd:cd06950   172 tQPARFGKLLLLLPSLRFI 190

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        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1622871068  58 RTCLICGDRATGLHYGIISCEGCKGFFKRSICNKRV--YRCSRDKNCVMSRKQRNRCQYCRLLKCLQMGMNRK 128
Cdd:cd07157     1 QTCQVCGEPAAGFHHGAYVCEACKKFFMRSSNAISFtiSECPNGGKCIIDKKNRTKCQACRYRKCLNVGMSLG 73

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 1622871068 281 ELFALLCRLADELLFRQIAWIKKLPFFCELSIKDYTCLLSSTWQELILLSSLTVYSKQiFGELADVTAKYSpSDEELHRF 360
Cdd:cd06929     2 EKFDHFTEIMTVAIRRVVEFAKRIPGFRELSQEDQIALLKGGCFEILLLRSATLYDPE-KNSLTFGDGKGN-SRDVLLNG 79