RING-H2 zinc finger domain; There are 8 cysteine/ histidine residues which are proposed to be the conserved residues involved in zinc binding. The protein, of which this domain is the conserved region, participates in diverse functions relevant to chromosome metabolism and cell cycle control.

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                  ....*....|....*....|....*....|....*....|....*.
gi 116235456  657 LCLMCQklVQPSELHPMA---CTHVLHKECIKFWaqTNTNDTCPFC 699
Cdd:pfam12678  13 PCPECQ--APGDDECPVVwgeCGHAFHLHCISRW--LKTNNTCPLC 54

H2 subclass of RING (RING-H2) fingers 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 different Cys/His patterns while some lack a single Cys or His residue at typical Zn ligand positions (the fourth or eighth zinc ligand is prevalently exchanged for an Asp, which can indeed chelate Zn in a RING finger as well). This family corresponds to the H2 subclass of RING (RING-H2) finger proteins that are characterized by containing C3H2C3-type canonical RING-H2 fingers or noncanonical RING-H2 finger variants, including C4HC3- (RING-CH alias RINGv), C3H3C2-, C3H2C2D-, C3DHC3-, and C4HC2H-type modified RING-H2 fingers. The canonical RING-H2 finger has been defined as C-X2-C-X(9-39)-C-X(1-3)-H-X(2-3)-H-X2-C-X(4-48)-C-X2-C, X is any amino acid and the number of X residues varies in different fingers. It binds two Zn ions in a unique "cross-brace" arrangement, which distinguishes it from tandem zinc fingers and other similar motifs. RING-H2 finger 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 serves as a scaffold 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 116235456 658 CLMCQKLVQPSE-LHPMACTHVLHKECIKFWAQtNTNDTCPFC 699
Cdd:cd16448    1 CVICLEEFEEGDvVRLLPCGHVFHLACILRWLE-SGNNTCPLC 42

RING finger, H2 subclass, found in RING finger proteins RNF121, RNF175 and similar proteins; This subfamily includes RNF121, RNF175 and similar proteins. RNF121 is an E3-ubiquitin ligase present in the endoplasmic reticulum (ER) and cis-Golgi compartments. It is a novel regulator of apoptosis. It also facilitates the degradation and membrane localization of voltage-gated sodium (NaV) channels, and thus plays a role in the quality control of NaV channels during their synthesis and subsequent transport to the membrane. Moreover, RNF121 acts as a broad regulator of nuclear factor kappaB (NF-kappaB) signaling since its silencing also dampens NF-kappaB activation following stimulation of toll-like receptors (TLRs), nod-like receptors (NLRs), RIG-I-like Receptors (RLRs) or after DNA damage. RNF121 contains five conserved transmembrane (TM) domains and a C3H2C2-type RING-H2 finger. RNF175 is an uncharacterized RING finger protein that shows high sequence similarity with RNF121. This family also includes Arabidopsis RING finger E3 ligase RHA2A, RHA2B, and their homologs. RHA2A is a positive regulator of abscisic acid (ABA) signaling during seed germination and early seedling development. RHA2B may play a role in the ubiquitin-dependent proteolysis pathway that respond to proteasome inhibition. All subfamily members contain a C3H2C3-type RING-H2 finger, which is responsible for E3-ubiquitin ligase activity.

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                 ....*....|....*....|....*....|....*....|....*....|.
gi 116235456 657 LCLMC-QKL-------VQPSELHPMACTHVLHKECIKFWAQTNTNDTCPFC 699
Cdd:cd16475    2 VCAVCgQKLdvddneeGIIEKTYKLSCNHVFHEFCIRGWCIVGKKQTCPYC 52

RING-H2 zinc finger domain; There are 8 cysteine/ histidine residues which are proposed to be the conserved residues involved in zinc binding. The protein, of which this domain is the conserved region, participates in diverse functions relevant to chromosome metabolism and cell cycle control.

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                  ....*....|....*....|....*....|....*....|....*.
gi 116235456  657 LCLMCQklVQPSELHPMA---CTHVLHKECIKFWaqTNTNDTCPFC 699
Cdd:pfam12678  13 PCPECQ--APGDDECPVVwgeCGHAFHLHCISRW--LKTNNTCPLC 54

RING finger, H2 subclass, found in E3 ubiquitin-protein ligase RNF6, RNF12, and similar proteins; RNF6 is an androgen receptor (AR)-associated protein that induces AR ubiquitination and promotes AR transcriptional activity. RNF6-induced ubiquitination may regulate AR transcriptional activity and specificity by modulating cofactor recruitment. RNF6 is overexpressed in hormone-refractory human prostate cancer tissues and required for prostate cancer cell growth under androgen-depleted conditions. RNF6 also regulates local serine/threonine kinase LIM kinase 1 (LIMK1) levels in axonal growth cones. RNF6-induced LIMK1 polyubiquitination is mediated via K48 of ubiquitin and leads to proteasomal degradation of the kinase. RNF6 binds and upregulates the Inha promoter, and functions as a transcription regulatory protein in the mouse sertoli cell. It acts as a potential tumor suppressor gene involved in the pathogenesis of esophageal squamous cell carcinoma (ESCC). RNF12, also known as LIM domain-interacting RING finger protein, or RING finger LIM domain-binding protein (R-LIM), is an E3 ubiquitin-protein ligase encoded by gene RLIM that is crucial for normal embryonic development in some species and for normal X inactivation in mice. It thus functions as a major sex-specific epigenetic regulator of female mouse nurturing tissues. RNF12 is widely expressed during embryogenesis, and mainly localizes to the cell nucleus, where it regulates the levels of many proteins, including CLIM, LMO, HDAC2, TRF1, SMAD7, and REX1, by proteasomal degradation. Both RNF6 and RNF12 contain a well conserved C3H2C3-type RING-H2 finger.

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gi 116235456 654 TCKLCLMcqKLVQPSELHPMACTHVLHKECIKFWAQTNTndTCPFC 699
Cdd:cd16467    1 ECTICLG--EYETGEKLRRLPCSHEFHSECVDRWLKENS--SCPIC 42

Modified RING finger, H2 subclass (C3H2C2D-type), found in zinc finger SWIM domain-containing protein 2 (ZSWIM2) and similar proteins; ZSWIM2, also known as MEKK1-related protein X (MEX) or ZZ-type zinc finger-containing protein 2, is a testis-specific E3 ubiquitin ligase that promotes death receptor-induced apoptosis through Fas, death receptor (DR) 3 and DR4 signaling. ZSWIM2 is self-ubiquitinated and targeted for degradation through the proteasome pathway. It acts as an E3 ubiquitin ligase, through the E2, Ub-conjugating enzymes UbcH5a, UbcH5c, or UbcH6. ZSWIM2 contains four putative zinc-binding domains including an N-terminal SWIM (SWI2/SNF2 and MuDR) domain critical for its ubiquitination, and two modified RING-H2 fingers separated by a ZZ zinc finger domain, which was required for interaction with UbcH5a and its self-association. This model corresponds to the second RING-H2 finger, which is not a canonical C3H2C3-type, but a modified C3H2C2D-type.

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                 ....*....|....*....|....*....|....*....|....*
gi 116235456 655 CKLCLMCQKLVQPSELHPmaCTHVLHKECIKFWAQTNTNdTCPFC 699
Cdd:cd16486    2 CRICLKAFQLGQHVRTLP--CRHKFHRDCIDNWLLHSRN-SCPID 43

RING finger, H2 subclass, found in Arabidopsis thaliana RING-H2 finger A1a (RHA1A), A1b (RHA1B) and similar proteins; This subfamily includes Arabidopsis thaliana RHA1A, RHA1B and XERICO. RHA1A is a probable E3 ubiquitin-protein ligase that may possess E3 ubiquitin ligase activity in vitro. RHA1B possesses E3 ubiquitin-protein ligase activity when associated with the E2 enzyme UBC8 in vitro. XERICO functions on abscisic acid homeostasis at post-translational level, probably through ubiquitin/proteasome-dependent substrate-specific degradation. Members of this subfamily contain a C3H2C3-type RING-H2 finger.

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                 ....*....|....*....|....*....|....*....|....*.
gi 116235456 655 CKLCLmcQKLVQPSELHPMA-CTHVLHKECIKFWAQTNTNdTCPFC 699
Cdd:cd23121    4 CAICL--SDFNSDEKLRQLPkCGHIFHHHCLDRWIRYNKI-TCPLC 46

RING finger, H2 subclass, found in RING finger protein 103 (RNF103) and similar proteins; RNF103, also known as KF-1 or zinc finger protein 103 homolog (Zfp-103), is an endoplasmic reticulum (ER)-resident E3 ubiquitin-protein ligase that is widely expressed in many different organs, including brain, heart, kidney, spleen, and lung. It is involved in the ER-associated degradation (ERAD) pathway by interacting with components of the ERAD pathway, including Derlin-1 and VCP. RNF103 contains several hydrophobic regions at its N-terminal and middle regions, as well as a C-terminal C3H2C3-type RING-H2 finger.

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                 ....*....|....*....|....*....|....*....|....*...
gi 116235456 653 ATCKLCLMCqklVQPSELHP-MACTHVLHKECIKFWAQTnTNDTCPFC 699
Cdd:cd16473    5 EECAICLEN---YQNGDLLRgLPCGHVFHQNCIDVWLER-DNHCCPVC 48

RING finger, H2 subclass, found in protein E3 ubiquitin-protein ligase Praja-1, Praja-2, and similar proteins; This family includes two highly similar E3 ubiquitin-protein ligases, Praja-1 and Praja-2. Praja-1, also known as RING finger protein 70, is a RING-H2 finger ubiquitin ligase encoded by gene PJA1, a novel human X chromosome gene abundantly expressed in the brain. It has been implicated in bone and liver development, as well as memory formation and X-linked mental retardation (MRX). Praja-1 interacts with and activates the ubiquitin-conjugating enzyme UbcH5B, and shows E2-dependent E3 ubiquitin ligase activity. It is a 3-deazaneplanocin A (DZNep)-induced ubiquitin ligase that directly ubiquitinates individual polycomb repressive complex 2 (PRC2) subunits in a cell free system, which leads to their proteasomal degradation. It also plays an important role in neuronal plasticity, which is the basis for learning and memory. Moreover, Praja-1 ubiquitinates embryonic liver fodrin (ELF) and Smad3, but not Smad4, in a transforming growth factor-beta (TGF-beta)-dependent manner. It controls ELF abundance through ubiquitin-mediated degradation, and further regulates TGF-beta signaling, which plays a key role in the suppression of gastric carcinoma. Praja-1 also regulates the transcription function of the homeodomain protein Dlx5 by controlling the stability of Dlxin-1, via a ubiquitin-dependent degradation pathway. Praja-2, also known as RING finger protein 131, NEURODAP1, or KIAA0438, is an E2-dependent E3 ubiquitin ligase that interacts with and activates the ubiquitin-conjugating enzyme UbcH5B. It functions as an A-kinase anchoring protein (AKAP)-like E3 ubiquitin ligase that plays a critical role in controlling cyclic AMP (cAMP)-dependent PKA activity and pro-survival signaling, and further promotes cell proliferation and growth. Praja-2 is also involved in protein sorting at the postsynaptic density region of axosomatic synapses and possibly plays a role in synaptic communication and plasticity. Together with the AMPK-related kinase SIK2 and the CDK5 activator CDK5R1/p35, it forms a SIK2-p35-PJA2 complex that plays an essential role for glucose homeostasis in pancreatic beta cell functional compensation. Praja-2 ubiquitylates and degrades Mob, a core component of NDR/LATS kinase and a positive regulator of the tumor-suppressor Hippo signaling. Both Praja-1 and Praja-2 contain a potential nuclear localization signal (NLS) and a C-terminal C3H2C3-type RING-H2 motif.

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                 ....*....|....*....|....*....|....*....|....*.
gi 116235456 654 TCKLClmCQKLVQPSELHPMACTHVLHKECIKFWAQtnTNDTCPFC 699
Cdd:cd16465    1 CCPIC--CSEYVKDEIATELPCHHLFHKPCITAWLQ--KSGTCPVC 42

RING finger, H2 subclass, found in the PA-TM-RING ubiquitin ligase family; The PA-TM-RING family represents a group of transmembrane-type E3 ubiquitin ligases, which has been characterized by an N-terminal transient signal peptide, a PA (protease-associated) domain, a TM (transmembrane) domain, as well as a C-terminal C3H2C3-type RING-H2 finger domain. It includes RNF13, RNF167, ZNRF4 (zinc and RING finger 4), GRAIL (gene related to anergy in lymphocytes)/RNF128, RNF130, RNF133, RNF148, RNF149 and RNF150 (which are more closely related), as well as RNF43 and ZNRF3, which have substantially longer C-terminal tail extensions compared with the others. PA-TM-RING proteins are expressed at low levels in all mammalian tissues and species, but they are not present in yeast. They play a common regulatory role in intracellular trafficking/sorting, suggesting that abrogation of their function may result in dysregulation of cellular signaling events in cancer.

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gi 116235456 668 SELHPMACTHVLHKECIKFWAQtnTNDTCPFC 699
Cdd:cd16454   13 EKVRVLPCNHLFHKDCIDPWLE--QHNTCPLC 42

RING finger, H2 subclass, found in RING finger proteins RNF126, RNF115, and similar proteins; This subfamily includes RING finger proteins RNF126, RNF115, and similar proteins. RNF126 is a Bag6-dependent E3 ubiquitin ligase that is involved in the mislocalized protein (MLP) pathway of quality control. It regulates the retrograde sorting of the cation-independent mannose 6-phosphate receptor (CI-MPR). RNF126 promotes cancer cell proliferation by targeting the tumor suppressor p21 for ubiquitin-mediated degradation, and could be a novel therapeutic target in breast and prostate cancers. It is also able to ubiquitylate cytidine deaminase (AID), a poorly soluble protein that is essential for antibody diversification. RNF115, also known as Rab7-interacting ring finger protein (Rabring 7), or zinc finger protein 364 (ZNF364), or breast cancer-associated gene 2 (BCA2), is an E3 ubiquitin-protein ligase that is an endogenous inhibitor of adenosine monophosphate-activated protein kinase (AMPK) activation; this inhibition increases the efficacy of metformin in breast cancer cells. It also functions as a cofactor in the restriction imposed by tetherin on HIV-1, and targets HIV-1 Gag for lysosomal degradation, impairing virus assembly and release, in a tetherin-independent manner. Moreover, RNF115 is a Rab7-binding protein that stimulates c-Myc degradation through mono-ubiquitination of MM-1. It also plays crucial roles as a Rab7 target protein in vesicle traffic to late endosome/lysosome and lysosome biogenesis. RNF115 and RNF126 associate with the epidermal growth factor receptor (EGFR) and promote ubiquitylation of EGFR, suggesting they play a role in the ubiquitin-dependent sorting and downregulation of membrane receptors. Both of them contain an N-terminal BCA2 Zinc-finger domain (BZF), AKT-phosphorylation sites, and a C-terminal C3H2C3-type RING-H2 finger.

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                 ....*....|....*....|....*..
gi 116235456 673 MACTHVLHKECIKFWAQtnTNDTCPFC 699
Cdd:cd16667   18 LPCKHLFHPDCIVPWLE--LHNSCPVC 42

RING finger, H2 subclass, found in E3 ubiquitin-protein ligase RNF6 and similar proteins; RNF6 is an androgen receptor (AR)-associated protein that induces AR ubiquitination and promotes AR transcriptional activity. RNF6-induced ubiquitination may regulate AR transcriptional activity and specificity by modulating cofactor recruitment. RNF6 is overexpressed in hormone-refractory human prostate cancer tissues and required for prostate cancer cell growth under androgen-depleted conditions. Moreover, RNF6 regulates local serine/threonine kinase LIM kinase 1 (LIMK1) levels in axonal growth cones. RNF6-induced LIMK1 polyubiquitination is mediated via K48 of ubiquitin and leads to proteasomal degradation of the kinase. RNF6 also binds and upregulates the Inha promoter, and functions as a transcription regulatory protein in the mouse sertoli cell. RNF6 also acts as a potential tumor suppressor gene involved in the pathogenesis of esophageal squamous cell carcinoma (ESCC). RNF6 contains an N-terminal coiled-coil domain, a Lys-X-X-Leu/Ile-X-X-Leu/Ile (KIL) motif, and a C-terminal C3H2C3-type RING-H2 finger which is responsible for its ubiquitin ligase activity. The KIL motif is present in a subset of RING-H2 proteins from organisms as evolutionarily diverse as human, mouse, chicken, Drosophila, Caenorhabditis elegans, and Arabidopsis thaliana.

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gi 116235456 654 TCKLCLmcQKLVQPSELHPMACTHVLHKECIKFWaqTNTNDTCPFC 699
Cdd:cd16673    2 TCSVCI--NEYATGNKLRRLPCAHEFHIHCIDRW--LSENSTCPIC 43

RING finger, H2 subclass, found in RING finger proteins RNF111, RNF165, and similar proteins; The family includes RING finger proteins RNF111, RNF165, and similar proteins. RNF111, also known as Arkadia, is a nuclear E3 ubiquitin-protein ligase that targets intracellular effectors and modulators of transforming growth factor beta (TGF-beta)/Nodal-related signaling for polyubiquitination and proteasome-dependent degradation. It also interacts with the clathrin-adaptor 2 (AP2) complex and regulates endocytosis of certain cell surface receptors, leading to modulation of epidermal growth factor (EGF) and possibly other signaling pathways. The N-terminal half of RNF111 harbors three SUMO-interacting motifs (SIMs). It thus functions as a SUMO-targeted ubiquitin ligase (STUbL) that directly links nonproteolytic ubiquitylation and SUMOylation in the DNA damage response, as well as triggers degradation of signal-induced polysumoylated proteins, such as the promyelocytic leukemia protein (PML). RNF165, also known as Arkadia-like 2, Arkadia2, or Ark2C, is an E3 ubiquitin ligase with homology to the C-terminal half of RNF111. It is expressed specifically in the nervous system, and can serve to amplify neuronal responses to specific signals. It acts as a positive regulator of bone morphogenetic protein (BMP)-Smad signaling that is involved in motor neuron (MN) axon elongation. Both RNF165 and RNF111 contain a C-terminal C3H2C3-type RING-H2 finger.

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gi 116235456 655 CKLCLmcQKLVQPSELHPMACTHVLHKECIKFWAQTNTndTCPFC 699
Cdd:cd16474    3 CTICL--SDFEEGEDVRRLPCMHLFHQECVDQWLSTNK--RCPIC 43