Interferon regulatory factor 2-binding protein zinc finger; IRF-2BP1 and IRF-2BP2 are nuclear transcriptional repressor proteins and can inhibit both enhancer-activated and basal transcription. They both contain N-terminal zinc finger represented in this family and C-terminal RING finger domains.

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gi 22003884    10 RRQSCYLCDLPRMPWAMIWDFSEPVCRGCVNYEGADRIEFVIETARQLKRAH 61
Cdd:pfam11261   1 RRQKCYLCDLPRGPWAMIWDFSEPVCRGCVNYEGADRIELVIDKARQLKRSH 52

Interferon regulatory factor 2-binding protein zinc finger; IRF-2BP1 and IRF-2BP2 are nuclear transcriptional repressor proteins and can inhibit both enhancer-activated and basal transcription. They both contain N-terminal zinc finger represented in this family and C-terminal RING finger domains.

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gi 22003884    10 RRQSCYLCDLPRMPWAMIWDFSEPVCRGCVNYEGADRIEFVIETARQLKRAH 61
Cdd:pfam11261   1 RRQKCYLCDLPRGPWAMIWDFSEPVCRGCVNYEGADRIELVIDKARQLKRSH 52

variant of RING finger, HC subclass, found in interferon regulatory factor 2 (IRF2)-binding protein 2 (IRF-2BP2); IRF-2BP2, also known as IRF-2-binding protein 2 or DIF-1, is a nuclear protein that binds to the C-terminal repression domain of IRF-2 and acts as an IRF-2-dependent transcriptional corepressor, both enhancer-activated and basal transcription. IRF-2BP2 also specifically interacts with the C-terminal domain of the nuclear factor of activated T cells NFAT1 transcription factor, and negatively regulates the NFAT1-dependent transactivation of NFAT-responsive promoters. Moreover, IRF2BP2 suppresses the transactivation activity of p53 on both Bax and p21 promoters. It also shows anti-apoptotic activity through the modulation of the death domain in NRIF3. In addition, IRF2BP2 functions as a cofactor of VGLL4 and plays a critical role controlling gene expression in skeletal, cardiac, and smooth muscle cells. It is a muscle-enriched transcription factor required to activate vascular endothelial growth factor-A (VEGF-A) expression. IRF-2BP2 contains an N-terminal C4-type zinc finger and a C-terminal variant C3HC4-type RING-HC finger. The zinc finger is responsible for the homo- and hetero-dimerization between different members of the IRF-2BP2 family. The RING-HC finger interacts with IRF2 and also with nuclear receptor interacting factor 3 (NRIF3).

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gi 22003884 691 PLCCTICHERLEDTHFVQCPSVPSHKFCFPCSRESIKAQGATGEVYCPSGEKCPLVGSNVPWAFMQG 757
Cdd:cd16716   1 PLCCTLCHERLEDTHFVQCPSVPSHKFCFPCSRESIKQQGATGEVYCPSGEKCPLVGSNVPWAFMQG 67

variant of RING finger, HC subclass, found in interferon regulatory factor 2-binding protein IRF-2BP1, IRF-2BP2, and similar proteins; This subfamily includes IRF-2BP1, IRF-2BP2, and their homolog, IRF-2BP-like, also known as IRF-2BPL or C14orf4. IRF-2BP1 and IRF-2BP2 are nuclear proteins that bind to the C-terminal repression domain of IRF-2 and act as IRF-2-dependent transcriptional corepressors, both enhancer-activated and basal transcription. IRF-2BPL is expressed in the mediobasal hypothalamus and plays a critical function in regulating the female reproductive neuroendocrine axis. All subfamily members contain a C-terminal variant C3HC4-type RING-HC finger.

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gi 22003884 692 LCCTICHERLEDTHFVQCPSVPSHKFCFPCSRESIKAQGATGEVYCPSGEKCPLVG 747
Cdd:cd16511   1 LCCTLCHERLEDTHFVQCPSVPSHKFCFPCSRDSIKRQGAGGEVYCPSGEKCPLVG 56

HC subclass of RING (RING-HC) finger and its variants; The RING finger is a specialized type of Zn-finger of 40 to 60 residues that binds two atoms of zinc. It is defined by the "cross-brace" motif that chelates zinc atoms by eight amino acid residues, typically Cys or His, arranged in a characteristic spacing. Canonical RING motifs have been categorized into two major subclasses, RING-HC (C3HC4-type) and RING-H2 (C3H2C3-type), according to their Cys/His content. There are also many variants of RING fingers. Some have a different Cys/His pattern. Some lack a single Cys or His residue at typical Zn ligand positions, especially, the fourth or eighth zinc ligand is prevalently exchanged for an Asp, which can chelate Zn in a RING finger as well. This family corresponds to the HC subclass of RING (RING-HC) fingers that are characterized by containing C3HC4-type canonical RING-HC fingers or noncanonical RING-HC finger variants, including C4C4-, C3HC3D-, C2H2C4-, and C3HC5-type modified RING-HC fingers. The canonical RING-HC finger has been defined as C-X2-C-X(9-39)-C-X(1-3)-H-X(2-3)-C-X2-C-X(4-48)-C-X2-C. It binds two Zn ions in a unique "cross-brace" arrangement, which distinguishes it from tandem zinc fingers and other similar motifs. RING-HC fingers can be found in a group of diverse proteins with a variety of cellular functions, including oncogenesis, development, viral replication, signal transduction, the cell cycle, and apoptosis. Many of them are ubiquitin-protein ligases (E3s) that serve as scaffolds for binding to ubiquitin-conjugating enzymes (E2s, also referred to as ubiquitin carrier proteins or UBCs) in close proximity to substrate proteins, which enables efficient transfer of ubiquitin from E2 to the substrates.

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gi 22003884 692 LCCTICHERLEDTHFVQCpsvpSHKFCFPCSRESIKaqgaTGEVYCP 738
Cdd:cd16449   1 LECPICLERLKDPVLLPC----GHVFCRECIRRLLE----SGSIKCP 39