PHD finger superfamily; The PHD finger superfamily includes a canonical plant homeodomain (PHD) finger typically characterized as Cys4HisCys3, and a non-canonical extended PHD finger, characterized as Cys2HisCys5HisCys2His. Variations include the RAG2 PHD finger characterized by Cys3His2Cys2His and the PHD finger 5 found in nuclear receptor-binding SET domain-containing proteins characterized by Cys4HisCys2His. The PHD finger is also termed LAP (leukemia-associated protein) motif or TTC (trithorax consensus) domain. Single or multiple copies of PHD fingers have been found in a variety of eukaryotic proteins involved in the control of gene transcription and chromatin dynamics. PHD fingers can recognize the unmodified and modified histone H3 tail, and some have been found to interact with non-histone proteins. They also function as epigenome readers controlling gene expression through molecular recruitment of multi-protein complexes of chromatin regulators and transcription factors. The PHD finger domain SF is structurally similar to the RING and FYVE_like superfamilies.

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                 ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 569012403 503 ICICGQVcAGVESLQCDLCHDWFHGQCVTVPHLLSSVRAshTSSQLLAWWEWDTKFLCPLC 563
Cdd:cd15608    1 VCVCGQP-PRPGMLRCHLCQDWFHGGCVSFPRLLSSSGP--HSSPSLAWWEWDTRFLCPLC 58

PHD finger 2 found in Lysine-specific demethylase 5C (KDM5C) and 5D (KDM5D); The family includes KDM5C and KDM5D, both of which belong to the JARID subfamily within the JmjC proteins. KDM5C (also termed Histone demethylase JARID1C, Jumonji/ARIDdomain-containing protein 1C, SmcX, or Xe169) is a H3K4 trimethyl-histone demethylase that catalyzes demethylation of H3K4me3 and H3K4me2 to H3K4me1. It plays a role in neuronal survival and dendrite development. KDM5C defects are associated with X-linked mental retardation (XLMR). KDM5D (also termed Histocompatibility Y antigen (H-Y), Histone demethylase JARID1D, Jumonji/ARID domain-containing protein 1D, or SmcY) is a male-specific antigen that shows a demethylase activity specific for di- and tri-methylated histone H3K4 (H3K4me3 and H3K4me2), and has a male-specific function as a histone H3K4 demethylase by recruiting a meiosis-regulatory protein, MSH5, to condensed DNA. KDM5D directly interacts with a polycomb-like protein Ring6a/MBLR, and plays a role in regulation of transcriptional initiation through H3K4 demethylation. Both KDM5C and KDM5D contain the catalytic JmjC domain, JmjN, the BRIGHT domain, which is an AT-rich interacting domain (ARID), and a Cys5HisCys2 zinc finger, as well as two plant homeodomain (PHD) fingers. This model corresponds to the second PHD finger.

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                 ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 569012403 503 ICICGQVcAGVESLQCDLCHDWFHGQCVTVPHLLSSVRAshTSSQLLAWWEWDTKFLCPLC 563
Cdd:cd15608    1 VCVCGQP-PRPGMLRCHLCQDWFHGGCVSFPRLLSSSGP--HSSPSLAWWEWDTRFLCPLC 58

PHD zinc finger; The plant homeodomain (PHD) finger is a C4HC3 zinc-finger-like motif found in nuclear proteins thought to be involved in epigenetics and chromatin-mediated transcriptional regulation. The PHD finger binds two zinc ions using the so-called 'cross-brace' motif and is thus structurally related to the RING finger and the FYVE finger. It is not yet known if PHD fingers have a common molecular function. Several reports suggest that it can function as a protein-protein interacton domain and it was recently demonstrated that the PHD finger of p300 can cooperate with the adjacent BROMO domain in nucleosome binding in vitro. Other reports suggesting that the PHD finger is a ubiquitin ligase have been refuted as these domains were RING fingers misidentified as PHD fingers.

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                   ....*....|....*....|....*....|....*....|....*....|....*....|
gi 569012403   504 CICGQVCAGVESLQCDLCHDWFHGQCVTVPhllssvrashtssqlLAWWEWDTKFLCPLC 563
Cdd:smart00249   3 SVCGKPDDGGELLQCDGCDRWYHQTCLGPP---------------LLEEEPDGKWYCPKC 47

PHD finger 2 found in Lysine-specific demethylase 5C (KDM5C) and 5D (KDM5D); The family includes KDM5C and KDM5D, both of which belong to the JARID subfamily within the JmjC proteins. KDM5C (also termed Histone demethylase JARID1C, Jumonji/ARIDdomain-containing protein 1C, SmcX, or Xe169) is a H3K4 trimethyl-histone demethylase that catalyzes demethylation of H3K4me3 and H3K4me2 to H3K4me1. It plays a role in neuronal survival and dendrite development. KDM5C defects are associated with X-linked mental retardation (XLMR). KDM5D (also termed Histocompatibility Y antigen (H-Y), Histone demethylase JARID1D, Jumonji/ARID domain-containing protein 1D, or SmcY) is a male-specific antigen that shows a demethylase activity specific for di- and tri-methylated histone H3K4 (H3K4me3 and H3K4me2), and has a male-specific function as a histone H3K4 demethylase by recruiting a meiosis-regulatory protein, MSH5, to condensed DNA. KDM5D directly interacts with a polycomb-like protein Ring6a/MBLR, and plays a role in regulation of transcriptional initiation through H3K4 demethylation. Both KDM5C and KDM5D contain the catalytic JmjC domain, JmjN, the BRIGHT domain, which is an AT-rich interacting domain (ARID), and a Cys5HisCys2 zinc finger, as well as two plant homeodomain (PHD) fingers. This model corresponds to the second PHD finger.

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                 ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 569012403 503 ICICGQVcAGVESLQCDLCHDWFHGQCVTVPHLLSSVRAshTSSQLLAWWEWDTKFLCPLC 563
Cdd:cd15608    1 VCVCGQP-PRPGMLRCHLCQDWFHGGCVSFPRLLSSSGP--HSSPSLAWWEWDTRFLCPLC 58

C5HC2 zinc finger; Predicted zinc finger with eight potential zinc ligand binding residues. This domain is found in Jumonji. This domain may have a DNA binding function.

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gi 569012403   27 CIKCKTTCFLSALACYDCPDSLVCLSHINDLCK-CSRNRQYLRYRYTLDELPAM 79
Cdd:pfam02928   1 CSFCKAYCYLSAVTCSKCSGKVVCLRHAKELCSdCPPSKRTLLYRYTDDELEAL 54

PHD zinc finger; The plant homeodomain (PHD) finger is a C4HC3 zinc-finger-like motif found in nuclear proteins thought to be involved in epigenetics and chromatin-mediated transcriptional regulation. The PHD finger binds two zinc ions using the so-called 'cross-brace' motif and is thus structurally related to the RING finger and the FYVE finger. It is not yet known if PHD fingers have a common molecular function. Several reports suggest that it can function as a protein-protein interacton domain and it was recently demonstrated that the PHD finger of p300 can cooperate with the adjacent BROMO domain in nucleosome binding in vitro. Other reports suggesting that the PHD finger is a ubiquitin ligase have been refuted as these domains were RING fingers misidentified as PHD fingers.

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                   ....*....|....*....|....*....|....*....|....*....|....*....|
gi 569012403   504 CICGQVCAGVESLQCDLCHDWFHGQCVTVPhllssvrashtssqlLAWWEWDTKFLCPLC 563
Cdd:smart00249   3 SVCGKPDDGGELLQCDGCDRWYHQTCLGPP---------------LLEEEPDGKWYCPKC 47

PHD finger found in PHD finger protein 3 (PHF3), and death-inducer obliterator variants Dido1, Dido2, and Dido3; PHF3 is a human homolog of yeast protein bypass of Ess1 (Bye1), a nuclear protein with a domain resembling the central domain in the transcription elongation factor TFIIS. It is ubiquitously expressed in normal tissues including brain, but its expression is significantly reduced or lost in glioblastomas. PHF3 contains an N-terminal plant homeodomain (PHD) finger, a central RNA polymerase II (Pol II)-binding TFIIS-like domain (TLD) domain, and a C-terminal Spen paralogue and orthologue C-terminal (SPOC) domain. This family also includes Dido gene encoding three alternative splicing variants (Dido1, 2, and 3), which have been implicated in a number of cellular processes such as apoptosis and chromosomal segregation, particularly in the hematopoietic system. Dido1 is important for maintaining embryonic stem (ES) cells and directly regulates the expression of pluripotency factors. It is the shortest isoform that contains only a highly conserved PHD finger responsible for the binding of histone H3 with a higher affinity for trimethylated lysine4 (H3K4me3). Gene Dido1 is a Bone morphogenetic protein (BMP) target gene and promotes BMP-induced melanoma progression. It also triggers apoptosis after nuclear translocation and caspase upregulation. Dido3 is the largest isoform and is ubiquitously expressed in all human tissues. It is dispensable for ES cell self-renewal and pluripotency, but is involved in the maintenance of stem cell genomic stability and tumorigenesis. Dido3 contains a PHD finger, a transcription elongation factor S-II subunit M (TFSIIM) domain, a SPOC module, and a long C-terminal region (CT) of unknown homology.

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gi 569012403 504 CICGQVCAGVESLQCDLCHDWFHGQCVTVphllssvrashTSSQLLAWWEWDTKFLCPLC 563
Cdd:cd15552    2 CICRKPHNNRFMICCDRCEEWFHGDCVGI-----------TEAQGKEMEENIEEYVCPKC 50

PHD finger found in Saccharomyces cerevisiae extracellular matrix protein 5 (Ecm5p), Schizosaccharomyces pombe Lid2 complex component Lid2p, and similar proteins; The family includes Saccharomyces cerevisiae Ecm5p, Schizosaccharomyces pombe Lid2 complex component Lid2p, and similar proteins. Ecm5p is a JmjC domain-containing protein that directly removes histone lysine methylation via a hydroxylation reaction. It associates with the yeast Snt2p and Rpd3 deacetylase, which may play a role in regulating transcription in response to oxidative stress. Ecm5p promotes oxidative stress tolerance, while Snt2p ultimately decreases tolerance. Ecm5p contains an N-terminal ARID domain, a JmjC domain, and a C-terminal plant homeodomain (PHD) finger. Lid2p is a trimethyl H3K4 (H3K4me3) demethylase responsible for H3K4 hypomethylation in heterochromatin. It interacts with the histone lysine-9 methyltransferase, Clr4, through the Dos1/Clr8-Rik1 complex, and mediates H3K9 methylation and small RNA production. It also acts cooperatively with the histone modification enzymes Set1 and Lsd1 and plays an essential role in cross-talk between H3K4 and H3K9 methylation in euchromatin. Lid2p contains a JmjC domain, three PHD fingers and a JmjN domain. This model includes the second PHD finger of Lid2p.

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gi 569012403 504 CICGQVCAGVeSLQCDLCHDWFHGQCVTVPHLLSSVrashtssqllawwewDTKFLCPLC 563
Cdd:cd15518    2 CFCRQGEGGT-MIECEICKEWYHVKCIKNGRWKLDD---------------DDKFVCPIC 45

PHD finger found in lysine-specific demethylase 7 (KDM7); KDM7, also termed JmjC domain-containing histone demethylation protein 1D (JHDM1D), or KIAA1718, is a dual histone demethylase that catalyzes demethylation of monomethylated and dimethylated H3K9 (H3K9me2/me1) and H3K27 (H3K27me2/me1), which functions as an eraser of silencing marks on chromatin during brain development. It also plays a tumor-suppressive role by regulating angiogenesis. KDM7 contains a plant homeodomain (PHD) that binds Lys4-trimethylated histone 3 (H3K4me3) and a jumonji domain that demethylates either H3K9me2 or H3K27me2.

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gi 569012403 516 LQCDLCHDWFHGQCVTV 532
Cdd:cd15640   15 IECDICKDWFHGSCVQV 31

PHD finger 1 found in Saccharomyces cerevisiae SANT domain-containing protein 2 (Snt2p) and similar proteins; Snt2p is a yeast protein that may function in multiple stress pathways. It coordinates the transcriptional response to hydrogen peroxide-mediated oxidative stress through interaction with Ecm5 and the Rpd3 deacetylase. Snt2p contains a bromo adjacent homology (BAH) domain, two canonical Cys4HisCys3 plant homeodomain (PHD) fingers, a non-canonical extended PHD (ePHD) finger, Cys2HisCys5HisCys2His, and a SANT (SWI3, ADA2, N-CoR and TFIIIB) DNA-binding domain; this model corresponds to the first canonical Cys4HisCys3 PHD finger.

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                 ....*....|....*....|....*....|
gi 569012403 504 CICGQVCAGVESLQCDLCHDWFHGQCVTVP 533
Cdd:cd15497    3 KVCKEWCASDDSVRCDECKVSYHLLCVDPP 32

PHD finger found in CXXC-type zinc finger protein 1 (Cfp1); Cfp1, also termed CpG-binding protein, or PHD finger and CXXC domain-containing protein 1 (PCCX1), is a specificity factor that binds to unmethylated CpGs and links H3K4me3 with CpG islands (CGIs). It integrates both promoter CpG content and gene activity for accurate trimethylation of histone H3 Lys 4 (H3K4me3) deposition in embryonic stem cells. Moreover, Cfp1 is an essential component of the SETD1 histone H3K4 methyltransferase complex and functions as a critical regulator of histone methylation, cytosine methylation, cellular differentiation, and vertebrate development. Cfp1 contains a plant homeodomain (PHD) finger, a CXXC domain, and a CpG binding protein zinc finger C-terminal domain. Its CXXC domain selectively binds to non-methylated CpG islands, following by a preference for a guanosine nucleotide.

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                 ....*....|....*....|....*....
gi 569012403 504 CICGQVCAGVESLQCDLCHDWFHGQCVTV 532
Cdd:cd15553    2 CICRSSDISRFMIGCDNCEEWYHGDCINI 30

PHD domain found in Saccharomyces cerevisiae bypass of ESS1 protein 1 (Bye1p), the E3 Sumo Ligase SIZ1, and similar proteins; Yeast Bye1p is a nuclear transcription factor with a domain resembling the central domain in the transcription elongation factor TFIIS and plays an inhibitory role during transcription elongation. It functions as a multicopy suppressor of Ess1, a peptidyl-prolyl cis-trans isomerase involved in proline isomerization of the C-terminal domain (CTD) of RNA polymerase II (Pol II). Bye1p contains an N-terminal plant homeodomain (PHD) finger, a central Pol II-binding TFIIS-like domain (TLD) domain, and a C-terminal Spen paralogue and orthologue C-terminal (SPOC) domain. The PHD domain binds to a histone H3 tail peptide containing trimethylated lysine 4 (H3K4me3). The TLD domain is responsible for the association with chromatin. Plant SIZ1 protein is a SUMO (small ubiquitin-related modifier) E3 ligase that facilitates conjugation of SUMO to substrate target proteins (sumoylation) and belongs to the protein inhibitor of activated STAT (PIAS) protein family. It negatively regulates abscisic acid (ABA) signaling, which is dependent on the bZIP transcripton factor ABI5. It also modulates plant growth and plays a role in drought stress response likely through the regulation of gene expression. SIZ1 functions as a floral repressor that not only represses the salicylic acid (SA)-dependent pathway, but also promotes FLOWERING LOCUS C (FLC) expression by repressing FLOWERING LOCUS D (FLD) activity through sumoylation. SIZ1 contains a PHD finger, which specifically binds methylated histone H3 at lysine 4 and arginine 2.

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gi 569012403 504 CICGQVCAGVESLQCDLCHDWFHGQCVTVPHLLSSVRASHTSsqllawwewdtKFLCPLC 563
Cdd:cd15570    2 CPCGSSMEDGSMIQCEGCKTWQHMDCVLIPDKPADGLPELPS-----------KFYCELC 50