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.

                           10        20        30        40
                   ....*....|....*....|....*....|....*....|....*
gi 1370472174  346 CYCRKPFAGRPMIECSLCGTWIHLSCAKIKKT--NVPDFFYCQKC 388
Cdd:smart00249   3 SVCGKPDDGGELLQCDGCDRWYHQTCLGPPLLeeEPDGKWYCPKC 47

PHD finger found in PHD finger proteins PHF13 and PHF23; PHF13, also termed survival time-associated PHD finger protein in ovarian cancer 1 (SPOC1), is a novel plant homeodomain (PHD) finger-containing protein that shows strong expression in spermatogonia and ovarian cancer cells, modulates chromatin structure and mitotic chromosome condensation, and is important for proper cell division. It is also required for spermatogonial stem cell differentiation and sustained spermatogenesis. The overexpression of PHF13 associates with unresectable carcinomas and shorter survival in ovarian cancer. PHF23, also termed PHD-containing protein JUNE-1, is a hypothetical protein with a PHD finger. It is encoded by gene PHF23 that acts as a candidate fusion partner for the nucleoporin gene NUP98. The NUP98-PHF23 fusion results from a cryptic translocation t(11;17)(p15;p13) in acute myeloid leukemia (AML).

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                  ....*....|....*....|....*....|....*....|....
gi 1370472174 345 TCYCRKPFAGRPMIECSLCGTWIHLSCAKIKKTNVPDFFYCQKC 388
Cdd:cd15546     1 TCFCGKPFAGRPMIECSECLTWIHLSCAKIRKNNVPEVFICQKC 44

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 1370472174 346 CYCRKPFAGRpMIECSLCGTWIHLSCAKIKKTNVP--DFFYCQKC 388
Cdd:cd15518     2 CFCRQGEGGT-MIECEICKEWYHVKCIKNGRWKLDddDKFVCPIC 45

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.

                           10        20        30        40
                   ....*....|....*....|....*....|....*....|....*
gi 1370472174  346 CYCRKPFAGRPMIECSLCGTWIHLSCAKIKKT--NVPDFFYCQKC 388
Cdd:smart00249   3 SVCGKPDDGGELLQCDGCDRWYHQTCLGPPLLeeEPDGKWYCPKC 47

PHD finger found in PHF2, PHF8 and KDM7; This family includes PHF2, PHF8, KDM7, and similar proteins. PHF2, also termed GRC5, or PHD finger protein 2, is a histone lysine demethylase ubiquitously expressed in various tissues. PHF8, also termed PHD finger protein 8, or KDM7B, is a monomethylated histone H4 lysine 20(H4K20me1) demethylase that transcriptionally regulates many cell cycle genes. It also preferentially acts on H3K9me2 and H3K9me1. PHF8 is modulated by CDC20-containing anaphase-promoting complex (APC (cdc20)) and plays an important role in the G2/M transition. It acts as a critical molecular sensor for mediating retinoic acid (RA) treatment response in RAR alpha-fusion-induced leukemia. Moreover, PHF8 is essential for cytoskeleton dynamics and is associated with X-linked mental retardation. 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. All family members contain a plant homeodomain (PHD) finger and a JmjC domain.

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                  ....*....|....*....|....*....|....*....|....*.
gi 1370472174 346 CYCRKPF-AGRPMIECSLCGTWIHLSCAKIKKTNVPDF--FYCQKC 388
Cdd:cd15554     2 CICRQPYdVTRFMIECDVCKDWFHGSCVGVEEHQANDIerYHCPNC 47

PHD finger found in transcription initiation factor TFIID subunit 3 (TAF3); TAF3 (also termed 140 kDa TATA box-binding protein-associated factor, TBP-associated factor 3, transcription initiation factor TFIID 140 kDa subunit (TAF140), or TAFII-140, is an integral component of TFIID) is a general initiation factor (GTF) that plays a key role in preinitiation complex (PIC) assembly through core promoter recognition. The interaction of H3K4me3 with TAF3 directs global TFIID recruitment to active genes, which regulates gene-selective functions of p53 in response to genotoxic stress. TAF3 is highly enriched in embryonic stem cells and is required for endoderm lineage differentiation and prevents premature specification of neuroectoderm and mesoderm. Moreover, TAF3, along with TRF3, forms a complex that is essential for myogenic differentiation. TAF3 contains a plant homeodomain (PHD) finger. This family also includes Drosophila melanogaster BIP2 (Bric-a-brac interacting protein 2) protein, which functions as an interacting partner of D. melanogaster p53 (Dmp53).

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                  ....*....|....*....|....*....|....*....|..
gi 1370472174 348 CRKPFAGRPMIECSLCGTWIHLSCAKIKKTNVPDF-FYCQKC 388
Cdd:cd15522     5 CKKPDDGSPMIGCDECDDWYHWECVGITDEPPEEDdWFCPKC 46

PHD finger found in mixed lineage leukemia 5 (MLL5); MLL5 is a histone methyltransferase that plays a key role in hematopoiesis, spermatogenesis and cell cycle progression. It contains a single plant homeodomain (PHD) finger followed by a catalytic SET domain. MLL5 can be recruited to E2F1-responsive promoters to stimulate H3K4 trimethylation and transcriptional activation by binding to the cell cycle regulator host cell factor (HCF-1), thereby facilitating the cell cycle G1 to S phase transition. It is also involved in mitotic fidelity and genomic integrity by modulating the stability of the chromosomal passenger complex (CPC) via the interaction with Borealin. Moreover, MLL5 is a component of a complex associated with retinoic acid receptor that requires GlcN Acylation of its SET domain in order to activate its histone lysine methyltransferase activity. It also participates in the camptothecin (CPT)-induced p53 activation. Furthermore, MLL5 indirectly regulates H3K4 methylation, represses cyclin A2 (CycA) expression, and promotes myogenic differentiation.

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                  ....*....|....*....|....*....|....*....|....
gi 1370472174 345 TCYCRKPFAGRPMIECSLCGTWIHLSCAKIKKTNVPDFFYCQKC 388
Cdd:cd15550     1 RCICGFEHDDGFMICCDKCSVWQHGDCMGIDRENIPDSYLCEQC 44

PHD finger found in Set1 complex component SPP1; Set1C component SPP1, also called COMPASS component Spp1, or Complex proteins associated with set1 protein Spp1, or Suppressor of PRP protein 1, is a component of the COMPASS complex that links histone methylation to initiation of meiotic recombination. It induces double-strand break (DSB) formation by tethering to recombinationally cold regions. SPP1 interacts with H3K4me3 and Mer2, a protein required for DSB formation, to promote recruitment of potential meiotic DSB sites to the chromosomal axis. SPP1 contains a PHD finger, a zinc binding motif.

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                  ....*....|....*....|....*....|....*....|....*
gi 1370472174 346 CYCRKPFAGRPMIECSLCGTWIHLSCAKIKKTNVP--DFFYCQKC 388
Cdd:cd16039     2 CICQKPDDGRWMIACDGCDEWYHFTCVNIPEADVElvDSFFCPPC 46

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 1370472174 346 CYCRKPFAGRPMIECSLCGTWIHLSCAKIKKT------NVPDFFYCQKC 388
Cdd:cd15570     2 CPCGSSMEDGSMIQCEGCKTWQHMDCVLIPDKpadglpELPSKFYCELC 50

PHD finger found in Transcription factor 19 (TCF-19), Lysine-specific demethylase KDM5A and KDM5B, and other similar proteins; TCF-19 was identified as a putative trans-activating factor with expression beginning at the late G1-S boundary in dividing cells. It functions as a novel islet factor necessary for proliferation and survival in the INS-1 beta cell line. It plays an important role in susceptibility to both Type 1 Diabetes Mellitus (T1DM) and Type 2 Diabetes Mellitus (T2DM); it has been suggested that it may positively impact beta cell mass under conditions of beta cell stress and increased insulin demand. KDM5A was originally identified as a retinoblastoma protein (Rb)-binding partner and its inactivation may be important for Rb to promote differentiation. It is involved in transcription through interaction with TBP, p107, nuclear receptors, Myc, Sin3/HDAC, Mad1, RBP-J, CLOCK, and BMAL1. KDM5B has a restricted expression pattern in the testis, ovary, and transiently in the mammary gland of the pregnant female and has been shown to be upregulated in breast cancer, prostate cancer, and lung cancer, suggesting a potential role in tumorigenesis. Both KDM5A and KDM5B function as trimethylated histone H3 lysine 4 (H3K4me3) demethylases. This family also includes Caenorhabditis elegans Lysine-specific demethylase 7 homolog (ceKDM7A). ceKDM7A (also termed JmjC domain-containing protein 1.2, PHD finger protein 8 homolog, or PHF8 homolog) is a plant homeodomain (PHD)- and JmjC domain-containing protein that functions as a histone demethylase specific for H3K9me2 and H3K27me2. The binding of the PHD finger to H3K4me3 guides H3K9me2- and H3K27me2-specific demethylation by its catalytic JmjC domain in a trans-histone regulation mechanism. In addition, this family includes plant protein OBERON 1 and OBERON 2, Alfin1-like (AL) proteins, histone acetyltransferases (HATs) HAC, and AT-rich interactive domain-containing protein 4 (ARID4).

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                  ....*....|....*....|....*....|...
gi 1370472174 358 IECSLCGTWIHLSCAKIK--KTNVPDFFYCQKC 388
Cdd:cd15517    17 VQCDGCDKWFHQFCLGLSneRYADEDKFKCPNC 49

PHD finger 2 found in Lysine-specific demethylase 5A (KDM5A); KDM5A (also termed Histone demethylase JARID1A, Jumonji/ARID domain-containing protein 1A, or Retinoblastoma-binding protein 2 (RBBP-2 or RBP2)) was originally identified as a retinoblastoma protein (Rb)-binding partner and its inactivation may be important for Rb to promote differentiation. It is involved in transcription through interacting with TBP, p107, nuclear receptors, Myc, Sin3/HDAC, Mad1, RBP-J, CLOCK, and BMAL1. KDM5A functions as a trimethylated histone H3 lysine 4 (H3K4me3) demethylase that belongs to the JARID subfamily within the JmjC proteins. It also displays DNA-binding activities that can recognize the specific DNA sequence CCGCCC. KDM5A contains the catalytic JmjC domain, JmjN, the BRIGHT domain, which is an AT-rich interacting domain (ARID), and a Cys5HisCys2 zinc finger, as well as three plant homeodomain (PHD) fingers. This model corresponds to the second PHD finger.

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                  ....*....|....*....|....*....|....
gi 1370472174 346 CYCRKPFAGRpMIECSLCGTWIHLSCAKIKKTNV 379
Cdd:cd15606     2 CICRKPFSGF-MLQCELCKDWFHSSCVPLPKSSS 34

PHD-like zinc-binding domain; The members of this family are annotated as containing PHD domain, but the zinc-binding region here is not typical of PHD domains. The conformation here is a well-conserved cysteine-histidine rich region spanning 90 residues, where the Cys and His are arranged as HxxC(31)CxxC(6)CxxCxxxxCxxxxHxxC (21)CxxH.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1370472174 309 STETSQDGDASSSEGEMRVMDEDImvesgdDSWDLITCYCRKPFaGrPMIECSL--CGTWIHLSCAK-------IKKTNV 379
Cdd:pfam13771   8 SPELVQRGNDSMGFPIEDIEKIPK------RRWKLKCYLCKKKG-G-ACIQCSKknCRRAFHVTCALeagllmqFDEDNG 79

                  ....*....
gi 1370472174 380 PDFFYCQKC 388
Cdd:pfam13771  80 TFKSYCKKH 88

PHD finger found in Arabidopsis thaliana AT-rich interactive domain-containing protein 4 (ARID4) and similar proteins; This family includes A. thaliana ARID4 (ARID domain-containing protein 4) and similar proteins. Their biological roles remain unclear, but they all contain an AT-rich interactive domain (ARID) and a plant homeodomain (PHD) finger at the C-terminus. ARID is a helix-turn-helix motif-based DNA-binding domain conserved in all eukaryotes. PHD fingers can recognize the unmodified and modified histone H3 tail, and some have been found to interact with non-histone proteins.

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gi 1370472174 347 YCRKPFAGRPMIECSLCGTWIHLSCAKIK-----KTNVPD--FFYCQKC 388
Cdd:cd15615     9 YEENEGDEKEWVQCDSCSEWVHFECDGRTglgafKYAKSDglQYVCPRC 57

PHD finger found in PHD finger protein 20 (PHF20) and PHD finger protein 20-like protein 1 (P20L1); PHF20, also termed Glioma-expressed antigen 2, or hepatocellular carcinoma-associated antigen 58, or novel zinc finger protein, or transcription factor TZP (referring to Tudor and zinc finger domain containing protein), is a regulator of NF-kappaB activation by disrupting recruitment of PP2A to p65. It also functions as a transcription factor that binds Akt and plays a role in Akt cell survival/growth signaling. Moreover, it transcriptionally regulates p53. The phosphorylation of PHF20 on Ser291 mediated by protein kinase B (PKB) is essential in tumorigenesis via the regulation of p53 mediated signaling. P20L1 is an active malignant brain tumor (MBT) domain-containing protein that binds to monomethylated lysine 142 on DNA (Cytosine-5) Methyltransferase 1 (DNMT1) (DNMT1K142me1) and colocalizes at the perinucleolar space in a SET7-dependent manner. Its MBT domain reads and controls enzyme levels of methylated DNMT1 in cells, thus representing a novel antagonist of DNMT1 proteasomal degradation. Both PHF20 and PHF20L1 contain an N-terminal MBT domain, two Tudor domains, a plant homeodomain (PHD) finger and the putative DNA-binding domains, AT hook and Cys2His2-type zinc finger.

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                  ....*....|....*....|....*....|....*....|....
gi 1370472174 346 CYCRKPFAGRPMIECSLCGTWIHLSCAKI-KKTNVPDFFYCQKC 388
Cdd:cd15549     2 CICGVNEENGLMIQCELCLCWQHGVCMGIeEEESVPERYVCYVC 45

PHD finger found in PHD finger protein 20 (PHF20); PHF20, also termed Glioma-expressed antigen 2, or hepatocellular carcinoma-associated antigen 58, or novel zinc finger protein, or transcription factor TZP (referring to Tudor and zinc finger domain containing protein), is a regulator of NF-kappaB activation by disrupting recruitment of PP2A to p65. It also functions as a transcription factor that binds Akt and plays a role in Akt cell survival/growth signaling. Moreover, it transcriptionally regulates p53. The phosphorylation of PHF20 on Ser291 mediated by protein kinase B (PKB) is essential in tumorigenesis via the regulation of p53 mediated signaling. PHF20 contains an N-terminal malignant brain tumor (MBT) domain, two Tudor domains, a plant homeodomain (PHD) finger and the putative DNA-binding domains, AT hook and Cys2His2-type zinc finger.

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                  ....*....|....*....|....*....|....*....|...
gi 1370472174 346 CYCRKPFAGRPMIECSLCGTWIHLSCAKIKKTNVPDFFYCQKC 388
Cdd:cd15634     2 CICEVQEENDFMIQCEECLCWQHGVCMGLLEDNVPEKYTCYIC 44

PHD finger found in PHD finger protein 3 (PHF3); 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.

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                  ....*....|....*....|....*....|....*....|....*...
gi 1370472174 347 YCRKPFAGRPMIECSLCGTWIH-----LSCAKIKKTNVPDFFY-CQKC 388
Cdd:cd15638     4 FCKKPHGNRFMVGCGRCDDWFHgdcvgLSLSQAQQMEEEDKEYvCVKC 51