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 291490783   3 IC--CMEGCEFNNSIsndehVRCWLCDEYAHAKCAGITDSVVEMIEG-RTGLKWTCETC 58
Cdd:cd15593    4 IClkCYEDNDYESKM-----MQCAKCDHWVHAKCEGLSDELYEILSSlPDSVVYSCAPC 57

PHD finger 3 found in Histone-lysine N-methyltransferase 2B (KMT2B); KMT2B, also termed trithorax homolog 2 or WW domain-binding protein 7 (WBP-7), is encoded by the gene that was first named myeloid/lymphoid or mixed-lineage leukemia 2 (MLL2), a second human homolog of Drosophila trithorax, located on chromosome 19. It belongs to the MLL subfamily of H3K4-specific histone lysine methyltransferases (KMT2) and is vital for normal mammalian embryonic development. KMT2B functions as the catalytic subunit in the MLL2 complex, which contains WDR5, RbBP5, ASH2L and DPY30 as integral core subunits required for the efficient methylation activity of the complex. The MLL2 complex is highly active and specific for histone 3 lysine 4 (H3K4) methylation, which stimulates chromatin transcription in a SAM- and H3K4-dependent manner. Moreover, KMT2B plays a critical role in memory formation through mediating hippocampal H3K4 di- and trimethylation. It is also required for RNA polymerase II association and protection from DNA methylation at the MagohB CpG island promoter. KMT2B contains a CxxC (x for any residue) zinc finger domain, three plant homeodomain (PHD) fingers, an extended PHD (ePHD) finger, Cys2HisCys5HisCys2His, two FY (phenylalanine tyrosine)-rich domains, and a SET (Suppressor of variegation, Enhancer of zeste, Trithorax) domain. This model corresponds to the third PHD finger.

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gi 291490783   3 IC--CMEGCEFNNSIsndehVRCWLCDEYAHAKCAGITDSVVEMIEG-RTGLKWTCETC 58
Cdd:cd15593    4 IClkCYEDNDYESKM-----MQCAKCDHWVHAKCEGLSDELYEILSSlPDSVVYSCAPC 57

PHD finger 3 found in Histone-lysine N-methyltransferase 2B (KMT2B); KMT2B, also termed trithorax homolog 2 or WW domain-binding protein 7 (WBP-7), is encoded by the gene that was first named myeloid/lymphoid or mixed-lineage leukemia 2 (MLL2), a second human homolog of Drosophila trithorax, located on chromosome 19. It belongs to the MLL subfamily of H3K4-specific histone lysine methyltransferases (KMT2) and is vital for normal mammalian embryonic development. KMT2B functions as the catalytic subunit in the MLL2 complex, which contains WDR5, RbBP5, ASH2L and DPY30 as integral core subunits required for the efficient methylation activity of the complex. The MLL2 complex is highly active and specific for histone 3 lysine 4 (H3K4) methylation, which stimulates chromatin transcription in a SAM- and H3K4-dependent manner. Moreover, KMT2B plays a critical role in memory formation through mediating hippocampal H3K4 di- and trimethylation. It is also required for RNA polymerase II association and protection from DNA methylation at the MagohB CpG island promoter. KMT2B contains a CxxC (x for any residue) zinc finger domain, three plant homeodomain (PHD) fingers, an extended PHD (ePHD) finger, Cys2HisCys5HisCys2His, two FY (phenylalanine tyrosine)-rich domains, and a SET (Suppressor of variegation, Enhancer of zeste, Trithorax) domain. This model corresponds to the third PHD finger.

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gi 291490783   3 IC--CMEGCEFNNSIsndehVRCWLCDEYAHAKCAGITDSVVEMIEG-RTGLKWTCETC 58
Cdd:cd15593    4 IClkCYEDNDYESKM-----MQCAKCDHWVHAKCEGLSDELYEILSSlPDSVVYSCAPC 57

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 291490783   3 ICCMEGCEFNNsisnDEHVRCWLCDEYAHAKCAGItdsvvEMIEGRTGLKWTCETC 58
Cdd:cd15517    3 GICNLETAAVD----ELWVQCDGCDKWFHQFCLGL-----SNERYADEDKFKCPNC 49