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

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1143076912 555 PPQKTCLICGDEASGCHYGALTCGSCKVFFKRAAEGKQKYLCASRNDCTIDKFRRKNCPSCRLRKCYEAGMTLGEK 630
Cdd:cd07173     1 PPQKTCLICGDEASGCHYGALTCGSCKVFFKRAAEGKQKYLCASRNDCTIDKFRRKNCPSCRLRKCFEAGMTLGAR 76

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

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1143076912 555 PPQKTCLICGDEASGCHYGALTCGSCKVFFKRAAEGKQKYLCASRNDCTIDKFRRKNCPSCRLRKCYEAGMTLGEK 630
Cdd:cd07173     1 PPQKTCLICGDEASGCHYGALTCGSCKVFFKRAAEGKQKYLCASRNDCTIDKFRRKNCPSCRLRKCFEAGMTLGAR 76

c4 zinc finger in nuclear hormone receptors;

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                   ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1143076912  559 TCLICGDEASGCHYGALTCGSCKVFFKRAAEGKQKYLCASRNDCTIDKFRRKNCPSCRLRKCYEAGMT 626
Cdd:smart00399   1 LCCVCGDHASGFHFGVCSCRACKAFFRRTVNLRYKYRCDRKNNCSINKRYRCRCRACRLKKCLGVGMD 68

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

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1143076912 555 PPQKTCLICGDEASGCHYGALTCGSCKVFFKRAAEGKQKYLCASRNDCTIDKFRRKNCPSCRLRKCYEAGMTLGEK 630
Cdd:cd07173     1 PPQKTCLICGDEASGCHYGALTCGSCKVFFKRAAEGKQKYLCASRNDCTIDKFRRKNCPSCRLRKCFEAGMTLGAR 76

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        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1143076912 560 CLICGDEASGCHYGALTCGSCKVFFKRAAEGKQKYLCASRNDCTIDKFRRKNCPSCRLRKCYEAGMTLGEK 630
Cdd:cd06963     1 CLICGDEASGCHYGVLTCGSCKVFFKRAAEGQHNYLCAGRNDCIIDKIRRKNCPACRLRKCYQAGMTLGAR 71

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.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1143076912 559 TCLICGDEASGCHYGALTCGSCKVFFKRAAEGKQKYLCASRNDCTIDKFRRKNCPSCRLRKCYEAGMT 626
Cdd:pfam00105   1 LCKVCGDKASGYHYGVLTCEGCKGFFRRSIQKNIVYTCKFNKDCVIDKRNRNRCQYCRLKKCLEVGMS 68

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 1143076912 556 PQKTCLICGDEASGCHYGALTCGSCKVFFKRAAEGKQKYLCASRNDCTIDKFRRKNCPSCRLRKCYEAGMTLG 628
Cdd:cd07171     2 DTHFCAVCSDYASGYHYGVWSCEGCKAFFKRSIQGHNDYICPATNQCTIDKNRRKSCQACRLRKCYEVGMMKG 74

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).

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1143076912 560 CLICGDEASGCHYGALTCGSCKVFFKRAAEGKQKYLCASRNDCTIDKFRRKNCPSCRLRKCYEAGMTL 627
Cdd:cd07167     1 CPVCGDKVSGYHYGLLTCESCKGFFKRTVQNKKRYTCIENQNCQIDKTQRKRCPYCRFQKCLSVGMKL 68

DNA-binding domain of thyroid hormone receptors (TRs) is composed of two C4-type zinc fingers; DNA-binding domain of thyroid hormone receptors (TRs) is composed of two C4-type zinc fingers. Each zinc finger contains a group of four Cys residues which co-ordinates a single zinc atom. TR interacts with the thyroid response element, which is a DNA site with direct repeats of the consensus sequence 5'-AGGTCA-3' separated by one to five base pairs, upstream of target genes and modulates the rate of transcriptional initiation. Thyroid hormone receptor (TR) mediates the actions of thyroid hormones, which play critical roles in growth, development, and homeostasis in mammals. They regulate overall metabolic rate, cholesterol and triglyceride levels, and heart rate, and affect mood. TRs are expressed from two separate genes (alpha and beta) in human and each gene generates two isoforms of the receptor through differential promoter usage or splicing. TRalpha functions in the heart to regulate heart rate and rhythm and TRbeta is active in the liver and other tissues. The unliganded TRs function as transcription repressors, by binding to thyroid hormone response elements (TRE) predominantly as homodimers, or as heterodimers with retinoid X-receptors (RXR), and being associated with a complex of proteins containing corepressor proteins. Ligand binding promotes corepressor dissociation and binding of a coactivator to activate transcription. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, TR has a central well conserved DNA binding domain (DBD), a variable N-terminal domain, a flexible hinge and a C-terminal ligand binding domain (LBD).

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1143076912 560 CLICGDEASGCHYGALTCGSCKVFFKRAAEGKQKYLCASRNDCTIDKFRRKNCPSCRLRKCYEAGMT----LGEKFRVGN 635
Cdd:cd06961     2 CVVCGDKATGYHYRCITCEGCKGFFRRTVQKKLSYSCKGEGKCEIDKVTRNQCQECRFKKCIAVGMAkdlvLDDRKRGAK 81

                  ...
gi 1143076912 636 CKH 638
Cdd:cd06961    82 RKL 84

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).

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1143076912 558 KTCLICGDEASGCHYGALTCGSCKVFFKRAAEGKQKYLCASRNDCTIDKFRRKNCPSCRLRKCYEAGMTL 627
Cdd:cd07168     7 KLCSICEDKATGLHYGIITCEGCKGFFKRTVQNKRVYTCVGDGRCEITKAQRNRCQYCRFRKCIRKGMML 76

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

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1143076912 555 PPQKTCLICGDEASGCHYGALTCGSCKVFFKRAAEGKQKYLCASRNDCTIDKFRRKNCPSCRLRKCYEAGM 625
Cdd:cd06967     1 QPVELCVVCGDKASGRHYGAVSCEGCKGFFKRSIRKNLGYSCRGSKDCVINKHHRNRCQYCRLQKCLAMGM 71

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).

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1143076912 557 QKTCLICGDEASGCHYGALTCGSCKVFFKRAAEGKQKYLCASRNDCTIDKFRRKNCPSCRLRKCYEAGMTL 627
Cdd:cd07169     6 QRTCLICGDRATGLHYGIISCEGCKGFFKRSICNKRVYRCSRDKNCVMSRKQRNRCQYCRLLKCLQMGMNR 76

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).

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 1143076912 558 KTCLICGDEASGCHYGALTCGSCKVFFKRAAEGKQKYLCASRNDCTIDKFRRKNCPSCRLRKCYEAGMT 626
Cdd:cd06964     5 KPCFVCQDKSSGYHYGVSACEGCKGFFRRSIQKNMVYTCHRDKNCIINKVTRNRCQYCRLQKCFEVGMS 73

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).

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1143076912 560 CLICGDEASGCHYGALTCGSCKVFFKRAAEGKQKYLCASRN-DCTIDKFRRKNCPSCRLRKCYEAGM 625
Cdd:cd07154     1 CKVCGDRSSGKHYGVYACDGCSGFFKRSIRRNLLYTCKAGNgSCVVDKARRNQCQACRLKKCLEVSM 67

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

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1143076912 558 KTCLICGDEASGCHYGALTCGSCKVFFKR--AAEGKQKYLCASRNDCTIDKFRRKNCPSCRLRKCYEAGMTLG 628
Cdd:cd07157     1 QTCQVCGEPAAGFHHGAYVCEACKKFFMRssNAISFTISECPNGGKCIIDKKNRTKCQACRYRKCLNVGMSLG 73

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

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1143076912 560 CLICGDEASGCHYGALTCGSCKVFFKRAAEGKQKYLCASRNDCTIDKFRRKNCPSCRLRKCYEAGM 625
Cdd:cd06962     4 CVVCGDKASGYHYNALTCEGCKGFFRRSITKNAVYKCKNGGNCEMDMYMRRKCQECRLRKCKEMGM 69

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

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1143076912 560 CLICGDEASGCHYGALTCGSCKVFFKRAAEGKQKYLCASRNDCTIDKFRRKNCPSCRLRKCYEAGM 625
Cdd:cd07160    21 CSVCGDKASGFHYNVLSCEGCKGFFRRSVIKGAQYVCKNGGKCQMDMYMRRKCQECRLRKCREAGM 86

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.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1143076912 560 CLICGDEASGCHYGALTCGSCKVFFKRAAEGKQKYLCASRNDCTIDKFRRKNCPSCRLRKCYEAGMT 626
Cdd:cd07179     1 CRVCGGKSSGFHFGALTCEGCKGFFRRTELSSNSYVCPGGQNCAITPATRNACKSCRFRRCLAVGMS 67

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
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1143076912 558 KTCLICGDEASGCHYGALTCGSCKVFFKRAAEGKQKYLCASRNDCTIDKFRRKNCPSCRLRKCYEAGM 625
Cdd:cd06955     7 RICGVCGDRATGFHFNAMTCEGCKGFFRRSMKRKALFTCPFNGDCRITKDNRRHCQACRLKRCVDIGM 74

DNA-binding domain of Drosophila ecdysone-induced protein 78 (E78) like is composed of two C4-type zinc fingers; DNA-binding domain of proteins similar to Drosophila ecdysone-induced protein 78 (E78) is composed of two C4-type zinc fingers. Each zinc finger contains a group of four Cys residues which coordinates a single zinc atom. E78 interacts with specific DNA sites upstream of the target gene and modulates the rate of transcriptional initiation. Drosophila ecdysone-induced protein 78 (E78) is a transcription factor belonging to the nuclear receptor superfamily. E78 is a product of the ecdysone-inducible gene found in an early late puff locus at position 78C during the onset of Drosophila metamorphosis. An E78 orthologue from the Platyhelminth Schistosoma mansoni (SmE78) has also been identified. It is the first E78 orthologue known outside of the molting animals--the Ecdysozoa. The SmE78 may be involved in transduction of an ecdysone signal in S. mansoni, consistent with its function in Drosophila. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, E78-like receptors have a central well conserved DNA-binding domain (DBD), a variable N-terminal domain, a non-conserved hinge and a C-terminal ligand binding domain (LBD).

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1143076912 560 CLICGDEASGCHYGALTCGSCKVFFKRAAEGKQKYLCASRNDCTIDKFRRKNCPSCRLRKCYEAGMT 626
Cdd:cd07165     1 CKVCGDKASGYHYGVTSCEGCKGFFRRSIQKQIEYRCLRDGKCEIIRLNRNRCQYCRFKKCLAAGMS 67

DNA-binding domain of the photoreceptor cell-specific nuclear receptor (PNR) is composed of two C4-type zinc fingers; DNA-binding domain of the photoreceptor cell-specific nuclear receptor (PNR) is composed of two C4-type zinc fingers. Each zinc finger contains a group of four Cys residues which co-ordinates a single zinc atom. PNR interacts with specific DNA sites upstream of the target gene and modulates the rate of transcriptional initiation. PNR is a member of the nuclear receptor superfamily of the ligand-activated transcription factors. PNR is expressed only in the outer layer of retinal photoreceptor cells. It may be involved in the signaling pathway regulating photoreceptor differentiation and/or maintenance. It most likely binds to DNA as a homodimer. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, PNR has a central well conserved DNA binding domain (DBD), a variable N-terminal domain, a flexible hinge and a C-terminal ligand binding domain (LBD).

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gi 1143076912 556 PQKTCLICGDEASGCHYGALTCGSCKVFFKRAAEGKQKYLC-ASRNDCTIDKFRRKNCPSCRLRKCYEAGM 625
Cdd:cd06970     5 PGLLCRVCGDTSSGKHYGIYACNGCSGFFKRSVRRKLIYRCqAGTGMCPVDKAHRNQCQACRLKKCLQAGM 75

DNA-binding domain of REV-ERB receptor-like is composed of two C4-type zinc fingers; DNA-binding domain of REV-ERB receptor- like is composed of two C4-type zinc fingers. Each zinc finger contains a group of four Cys residues which coordinates a single zinc atom. This domain interacts with specific DNA sites upstream of the target gene and modulates the rate of transcriptional initiation. REV-ERB receptors are transcriptional regulators belonging to the nuclear receptor superfamily. They regulate a number of physiological functions including the circadian rhythm, lipid metabolism, and cellular differentiation. REV-ERB receptors bind as a monomer to a (A/G)GGTCA half-site with a 5' AT-rich extension or as a homodimer to a direct repeat 2 element (AGGTCA sequence with a 2-bp spacer), indicating functional diversity. When bound to the DNA, they recruit corepressors (NcoR/histone deacetylase 3) to the promoter, resulting in repression of the target genes. The porphyrin heme has been demonstrated to function as a ligand for REV-ERB receptor. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, REV-ERB receptors have a central well conserved DNA binding domain (DBD), a variable N-terminal domain, a non-conserved hinge and a C-terminal ligand binding domain (LBD).

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gi 1143076912 560 CLICGDEASGCHYGALTCGSCKVFFKRAAEGKQKYLCASRND-CTIDKFRRKNCPSCRLRKCYEAGMT 626
Cdd:cd07166     6 CKVCGDKASGFHYGVHACEGCKGFFRRSIQQKIQYRKCTKNEtCSIMRINRNRCQYCRFKKCLAVGMS 73

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).

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gi 1143076912 560 CLICGDEASGCHYGALTCGSCKVFFKRAAEGKQKYLCASRNdCTIDKFRRKNCPSCRLRKCYEAGMT 626
Cdd:cd06965     2 CRVCGDKASGFHYGVHACEGCKGFFRRTIRLKLVYKPCDLS-CKIHKKSRNKCQYCRFQKCLNVGMS 67