C2HC Zing finger domain; This is a zinc finger domain together with a linker region found in RNF125, a small protein (25kD) that contains a RING domain, three zinc fingers (ZnFs) and a ubiquitin interacting motif (UIM). The C2HC ZnF plays an essential role in the interaction of RNF125 with the E2 UbcH5a, which originates from the requirement of the C2HC-ZnF for the structural stability of the RING domain. A mutation at one of the contact residues in the C2HC-ZnF, a highly conserved M112, resulted in the loss of ubiquitin ligase activity. Furthermore, mutations at the Zn2+ chelating cysteine residues, C100 and C103 of this domain resulted in a loss of activity.

                          10        20        30
                  ....*....|....*....|....*....|...
gi 21361539    80 RKFSGSCRCCAKQIKFYRMRHHYKSCKKYQDEY 112
Cdd:pfam18574   1 ESTEGNCRGCEKQVCLSKMRAHYATCEKYQEYY 33

Zinc finger, C3HC4 type (RING finger);

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|.
gi 21361539    17 YCPVCQEVLKTPVRTTACQHVFCRKCFLTAMRESGaHCPLC 57
Cdd:pfam13923   1 MCPICMDMLKDPSTTTPCGHVFCQDCILRALRAGN-ECPLC 40

Drought induced 19 protein (Di19), zinc-binding; This family consists of several drought induced 19 (Di19) like proteins. Di19 has been found to be strongly expressed in both the roots and leaves of Arabidopsis thaliana during progressive drought. This domain is a zinc-binding domain.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 21361539   155 PTFKCPLCQEsNFTRQRLLDHCNSNHLFQIVPVTCPICVslpwgdpSQITRNFVSHLNQRH 215
Cdd:pfam05605   1 DEFTCPFCGE-DFDVVSLCEHVEDEHPVESKNVVCPVCA-------AKVGKDMIGHLTLQH 53

Ring finger; E3 ubiquitin-protein ligase activity is intrinsic to the RING domain of c-Cbl and is likely to be a general function of this domain; Various RING fingers exhibit binding activity towards E2 ubiquitin-conjugating enzymes (Ubc' s)

                           10        20        30        40
                   ....*....|....*....|....*....|....*....|
gi 21361539     18 CPVCQEVLKTPVRTTACQHVFCRKCFLTAMRESGAHCPLC 57
Cdd:smart00184   1 CPICLEEYLKDPVILPCGHTFCRSCIRKWLESGNNTCPIC 40

Zinc finger, C3HC4 type (RING finger);

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|.
gi 21361539    17 YCPVCQEVLKTPVRTTACQHVFCRKCFLTAMRESGaHCPLC 57
Cdd:pfam13923   1 MCPICMDMLKDPSTTTPCGHVFCQDCILRALRAGN-ECPLC 40

RING finger, HC subclass, found in breast cancer type 1 susceptibility protein (BRCA1) and similar proteins; BRCA1, also known as RING finger protein 53 (RNF53), is a RING finger protein encoded by the tumor suppressor gene BRCA1 that regulates all DNA double-strand break (DSB) repair pathways. BRCA1 is frequently mutated in patients with hereditary breast and ovarian cancer (HBOC). Its mutation is also associated with an increased risk of pancreatic, stomach, laryngeal, fallopian tube, and prostate cancer. It plays an important role in the DNA damage response signaling and has been implicated in various cellular processes such as cell cycle regulation, transcriptional regulation, chromatin remodeling, DNA DSBs, and apoptosis. BRCA1 contains an N-terminal C3HC4-type RING-HC finger, and two BRCT (BRCA1 C-terminus domain) repeats at the C-terminus.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 21361539   1 MAEDLSAATSYTEDDFYCPVCQEVLKTPVrTTACQHVFCRKCFLTAM--RESGAHCPLCRGNVTRR 64
Cdd:cd16498   2 RIERVQEVISAMQKNLECPICLELLKEPV-STKCDHQFCRFCILKLLqkKKKPAPCPLCKKSVTKR 66

RING finger, HC subclass, found in really interesting new gene 1 protein (RING1) and similar proteins; RING1, also known as polycomb complex protein RING1, RING finger protein 1 (RNF1), or RING finger protein 1A (RING1A), was identified as a transcriptional repressor that is associated with the Polycomb group (PcG) protein complex involved in stable repression of gene activity. It is a core component of polycomb repressive complex 1 (PRC1) that functions as an E3-ubuiquitin ligase that transferring the mono-ubuiquitin mark to the C-terminal tail of Histone H2A at K118/K119. PRC1 is also capable of chromatin compaction, a function not requiring histone tails, and this activity appears important in gene silencing. RING1 interacts with multiple PcG proteins and displays tumorigenic activity. It also shows zinc-dependent DNA binding activity. Moreover, RING1 inhibits transactivation of the DNA-binding protein recombination signal binding protein-Jkappa (RBP-J) by Notch through interaction with the LIM domains of KyoT2. RING1 contains a C3HC4-type RING-HC finger.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 21361539  13 EDDFYCPVCQEVLKTPVRTTACQHVFCRKCFLTAMRESGAHCPLCRGNVTRRERACPERALDL 75
Cdd:cd16739   1 HSELMCPICLDMLKNTMTTKECLHRFCSDCIVTALRSGNKECPTCRKKLVSKRSLRPDPNFDA 63

RING finger, HC subclass, found in really interesting new gene proteins RING1, RING2 and similar proteins; RING1, also known as polycomb complex protein RING1, RING finger protein 1 (RNF1), or RING finger protein 1A (RING1A), is a transcriptional repressor that is associated with the Polycomb group (PcG) protein complex involved in stable repression of gene activity. RING2, also known as huntingtin-interacting protein 2-interacting protein 3, HIP2-interacting protein 3, protein DinG, RING finger protein 1B (RING1B), RING finger protein 2 (RNF2), or RING finger protein BAP-1, is an E3 ubiquitin-protein ligase that interacts with both nucleosomal DNA and an acidic patch on histone H4 to achieve the specific monoubiquitination of K119 on histone H2A (H2AK119ub), thereby playing a central role in histone code and gene regulation. Both RING1 and RING2 are core components of polycomb repressive complex 1 (PRC1) that functions as an E3-ubuiquitin ligase transferring the mono-ubuiquitin mark to the C-terminal tail of Histone H2A at K118/K119. PRC1 is also capable of chromatin compaction, a function not requiring histone tails, and this activity appears important in gene silencing. RING2 acts as the main E3 ubiquitin ligase on histone H2A of the PRC1 complex, while RING1 may rather act as a modulator of RNF2/RING2 activity. Members of this family contain a C3HC4-type RING-HC finger.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 21361539  15 DFYCPVCQEVLKTPVRTTACQHVFCRKCFLTAMRESGAHCPLCRGNVTRR 64
Cdd:cd16531   1 ELMCPICLGIIKNTMTVKECLHRFCAECIEKALRLGNKECPTCRKHLPSR 50

RING finger, HC subclass, found in really interesting new gene 2 protein (RING2) and similar proteins; RING2, also known as huntingtin-interacting protein 2-interacting protein 3, HIP2-interacting protein 3, protein DinG, RING finger protein 1B (RING1B), RING finger protein 2 (RNF2), or RING finger protein BAP-1, is an E3 ubiquitin-protein ligase that interacts with both nucleosomal DNA and an acidic patch on histone H4 to achieve the specific monoubiquitination of K119 on histone H2A (H2AK119ub), thereby playing a central role in histone code and gene regulation. RING2 is a core component of polycomb repressive complex 1 (PRC1) that functions as an E3-ubuiquitin ligase transferring the mono-ubuiquitin mark to the C-terminal tail of Histone H2A at K118/K119. PRC1 is also capable of chromatin compaction, a function not requiring histone tails, and this activity appears important in gene silencing. The enzymatic activity of RING2 is enhanced by the interaction with BMI1/PCGF4, and it is dispensable for early embryonic development and much of the gene repression activity of PRC1. Moreover, RING2 plays a key role in terminating neural precursor cell (NPC)-mediated production of subcerebral projection neurons (SCPNs) during neocortical development. It also plays a critical role in nonhomologous end-joining (NHEJ)-mediated end-to-end chromosome fusions. Furthermore, RING2 is essential for expansion of hepatic stem/progenitor cells. It promotes hepatic stem/progenitor cell expansion through simultaneous suppression of cyclin-dependent kinase inhibitors (CDKIs) Cdkn1a and Cdkn2a, known negative regulators of cell proliferation. RING2 also negatively regulates p53 expression through directly binding with both p53 and MDM2 and promoting MDM2-mediated p53 ubiquitination in selective cancer cell types to stimulate tumor development. RING2 contains a C3HC4-type RING-HC finger.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|
gi 21361539  15 DFYCPVCQEVLKTPVRTTACQHVFCRKCFLTAMRESGAHCPLCRGNVTRRERACPERALD 74
Cdd:cd16740  12 ELMCPICLDMLKNTMTTKECLHRFCADCIITALRSGNKECPTCRKKLVSKRSLRPDPNFD 71

Drought induced 19 protein (Di19), zinc-binding; This family consists of several drought induced 19 (Di19) like proteins. Di19 has been found to be strongly expressed in both the roots and leaves of Arabidopsis thaliana during progressive drought. This domain is a zinc-binding domain.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 21361539   155 PTFKCPLCQEsNFTRQRLLDHCNSNHLFQIVPVTCPICVslpwgdpSQITRNFVSHLNQRH 215
Cdd:pfam05605   1 DEFTCPFCGE-DFDVVSLCEHVEDEHPVESKNVVCPVCA-------AKVGKDMIGHLTLQH 53

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.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|
gi 21361539  18 CPVCQEVLKTPVrTTACQHVFCRKCFLTAMRESGAHCPLC 57
Cdd:cd16449   3 CPICLERLKDPV-LLPCGHVFCRECIRRLLESGSIKCPIC 41

RING finger, HC subclass, found in Arabidopsis thaliana proteolysis 1 protein (PRT1) and similar proteins; PRT1, also called RING-type E3 ubiquitin transferase PRT1, is an E3 ubiquitin-protein ligase that mediates ubiquitination and subsequent proteasomal degradation of target proteins. It functions in the N-end rule pathway of protein degradation, where it specifically recognizes and ubiquitinates proteins with an N-terminal bulky aromatic amino acid (Phe). It does not act on aliphatic hydrophobic and basic N-terminal residues (Arg or Leu) containing proteins. PRT1 contains a typical C3HC4-type RING-HC finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 21361539  14 DDFYCPVCQEVLKTPVrTTACQHVFCRKCFLTAM---RESgaHCPLCR 58
Cdd:cd23132   1 EEFLCCICLDLLYKPV-VLECGHVFCFWCVHRCMngyDES--HCPLCR 45

second RING finger, HC subclass, found in the LON peptidase N-terminal domain and RING finger protein family; The LON peptidase N-terminal domain and RING finger protein family includes LONRF1 (also known as RING finger protein 191 or RNF191), LONRF2 (also known as RING finger protein 192, RNF192, or neuroblastoma apoptosis-related protease), LONRF3 (also known as RING finger protein 127 or RNF127), which are characterized by containing two C3HC4-type RING-HC fingers, four tetratricopeptide (TPR) repeats, and an ATP-dependent protease La (LON) substrate-binding domain at the C-terminus. Their biological functions remain unclear. This model corresponds to the second RING-HC finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....
gi 21361539  15 DFYCPVCQEVLKTPVrTTACQHVFCRKCFLTAMrESGAHCPLCR 58
Cdd:cd16514   1 DLECSLCLRLLYEPV-TTPCGHTFCRACLERCL-DHSPKCPLCR 42

RING finger, HC subclass, found in tripartite motif-containing protein 47 (TRIM47) and similar proteins; TRIM47, also known as gene overexpressed in astrocytoma protein (GOA) or RING finger protein 100 (RNF100), belongs to the C-IV subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, a B-box, and two coiled coil domains, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain. It plays an important role in the process of dedifferentiation that is associated with astrocytoma tumorigenesis. This subfamily also includes RING finger protein 135 (RNF135). RNF135, also known as RIG-I E3 ubiquitin ligase (REUL) or Riplet, is a widely expressed E3 ubiquitin-protein ligase that consists of an N-terminal C3HC4-type RING-HC finger and C-terminal B30.2/SPRY and PRY motifs, but lacks the B-box and coiled-coil domains that are also typically present in TRIM proteins. RNF135 serves as a specific retinoic acid-inducible gene-I (RIG-I)-interacting protein that ubiquitinates RIG-I and specifically stimulates RIG-I-mediated innate antiviral activity to produce antiviral type-I interferon (IFN) during the early phase of viral infection. It also has been identified as a bio-marker and therapy target of glioblastoma. It associates with the ERK signal transduction pathway and plays a role in glioblastoma cell proliferation, migration and cell cycle.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*..
gi 21361539  16 FYCPVCQEVLKTPVrTTACQHVFCRKCfLTAMRESG----AHCPLCR 58
Cdd:cd16604   1 LSCPICLDLLKDPV-TLPCGHSFCMGC-LGALWGAGrggrASCPLCR 45

RING finger, HC subclass, found in checkpoint with forkhead and RING finger domains protein (CHFR); CHFR, also known as RING finger protein 196 (RNF196), is a checkpoint protein that delays entry into mitosis in response to stress. It functions as an E3 ubiquitin ligase that ubiquitinates and degrades its target proteins, such as Aurora-A, Plk1, Kif22, and PARP-1, which are critical for proper mitotic transitions. It also plays an important role in cell cycle progression and tumor suppression, and is negatively regulated by SUMOylation-mediated proteasomal ubiquitylation. Moreover, CHFR is involved in the early stage of the DNA damage response, which mediates the crosstalk between ubiquitination and poly-ADP-ribosylation. CHFR contains a fork head associated (FHA) domain and a C3HC4-type RING-HC finger.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 21361539  14 DDFYCPVCQEVLKTPVRTTACQHVFCRKCFLTAMRESGAHCPLCRGNVTR 63
Cdd:cd16503   1 ENLTCSICQDLLHDCVSLQPCMHNFCAACYSDWMERSNTECPTCRATVQR 50

RING finger, HC subclass, found in RING finger protein 168 (RNF168) and similar proteins; RNF168 is an E3 ubiquitin-protein ligase that promotes noncanonical K27 ubiquitination to signal DNA damage. It, together with RNF8, functions as a DNA damage response (DDR) factor that promotes a series of ubiquitylation events on substrates, such as H2A and H2AX with H2AK13/15 ubiquitylation, facilitates recruitment of repair factors p53-binding protein 1 (53BP1) or the RAP80-BRCA1 complex to sites of double-strand breaks (DSBs), and inhibits homologous recombination (HR) in cells deficient in the tumor suppressor BRCA1. RNF168 also promotes H2A neddylation, which antagonizes ubiquitylation of H2A and regulates DNA damage repair. Moreover, RNF168 forms a functional complex with RAD6A or RAD6B during the DNA damage response. RNF168 contains an N-terminal C3HC4-type RING-HC finger that catalyzes H2A-K15ub and interacts with H2A, and two MIU (motif interacting with ubiquitin) domains responsible for the interaction with K63 linked poly-ubiquitin.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|.
gi 21361539  18 CPVCQEVLKTPVrTTACQHVFCRKCFLTAMRESGAHCPLCR 58
Cdd:cd16550   3 CPICLEILVEPV-TLPCNHTLCMPCFQSTVEKASLCCPLCR 42

first RING finger, HC subclass, found in Arabidopsis thaliana ORTHRUS and similar proteins; This subfamily includes Arabidopsis thaliana ORTHRUS 1-5. They are E3 ubiquitin-protein ligases that may participate in CpG methylation-dependent transcriptional regulation and/or epigenetic transcriptional silencing. ORTHRUS 1 mediates ubiquitination with the E2 ubiquitin-conjugating enzymes UBC11, UBC8 and UBC8 homologs (e.g. UBC10, UBC11, UBC28 and UBC29) but not with UBC27, UBC30, UBC32, UBC34 and UBC36. ORTHRUS 2 and 5 mediate ubiquitination with the E2 ubiquitin-conjugating enzyme UBC11. ORTHRUS 1 and 2 promote methylation-mediated gene silencing leading, for example, to early flowering. They can bind to CpG, CpNpG, and CpNpN DNA motifs, with a strong preference for methylated forms, and with highest affinity for CpG substrates. Members of this subfamily contain two typical C3HC4-type RING-HC fingers. This model corresponds to the first one.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*
gi 21361539  14 DDFYCPVCQEVLKTPVrTTACQHVFCRKCFLTAMRESGAHCPLCR 58
Cdd:cd23138   1 DELNCSFCMQLPERPV-TTPCGHNFCLKCFQKWMGQGKKTCGTCR 44

RING finger, HC subclass, found in tripartite motif-containing protein 40 (TRIM40) and similar proteins; TRIM40, also known as probable E3 NEDD8-protein ligase or RING finger protein 35 (RNF35), is highly expressed in the gastrointestinal tract including the stomach, small intestine, and large intestine. It enhances neddylation of inhibitor of nuclear factor kappaB kinase subunit gamma (IKKgamma), inhibits the activity of nuclear factor-kappaB (NF-kappaB)-mediated transcription, and thus prevents inflammation-associated carcinogenesis in the gastrointestinal tract. TRIM40 belongs to the C-V subclass of the TRIM (tripartite motif) family of proteins that are defined by an N-terminal RBCC (RING, Bbox, and coiled coil) domain, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region, as well as an uncharacterized region positioned C-terminal to the RBCC domain.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*
gi 21361539  18 CPVCQEVLKTPVrTTACQHVFCRKCFLTAMRESGAH----CPLCR 58
Cdd:cd16583   8 CPICQEPLKEAV-STDCGHLFCRMCLTQHAKKASASgvfsCPVCR 51

Modified RING finger, HC subclass (C3HC3D-type), found in uncharacterized proteins similar to tumor necrosis factor (TNF) receptor-associated factor 4 (TRAF4); This subfamily corresponds to a group of uncharacterized proteins that shows high sequence similarity with tumor necrosis factor (TNF) receptor-associated factor 4 (TRAF4). TRAF4, also known as cysteine-rich domain associated with RING and Traf domains protein 1, or metastatic lymph node gene 62 protein (MLN 62), or RING finger protein 83 (RNF83), is a member of TRAF protein family, which mainly function in the immune system, where they mediate signaling through tumor necrosis factor receptors (TNFRs) and interleukin-1/Toll-like receptors (IL-1/TLRs). It also plays a critical role in the nervous system, as well as in carcinogenesis. Like TRAF4, members of this subfamily contain a modified C3HC3D-type RING-HC finger.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 21361539  13 EDDFYCPVCQEVLKTPVRTTACQHVFCRKCFLTAMRESGAhCPLCRGNVTR 63
Cdd:cd23126   2 DKKYECPVCCQVLRYPVQFEECGHRVCSSCLPELLRVEPR-CPIDQGPIDR 51

DNA repair protein rad18; All proteins in this family for which functions are known are involved in nucleotide excision repair.This family is based on the phylogenomic analysis of JA Eisen (1999, Ph.D. Thesis, Stanford University). [DNA metabolism, DNA replication, recombination, and repair]

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*.
gi 21361539    13 EDDFYCPVCQEVLKTPVrTTACQHVFCRKCFLTAMRESGaHCPLCR 58
Cdd:TIGR00599  24 DTSLRCHICKDFFDVPV-LTSCSHTFCSLCIRRCLSNQP-KCPLCR 67

RING-type zinc-finger; This zinc-finger is a typical RING-type of plant ubiquitin ligases.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|
gi 21361539    18 CPVCQEVLKTPVrtTACQHVFCRKCFLTAMRESG--AHCP 55
Cdd:pfam13445   1 CPICLELFTDPV--LPCGHTFCRECLEEMSQKKGgkFKCP 38

SP-RING finger and SPL-RING finger, variants of RING fingers; This family corresponds to a group of proteins with variants of RING fingers that are characterized by lacking the second, fifth, and sixth Zn2+ ion-coordinating residues compared with the classic C3H2C3-/C3HC4-type RING fingers. They include SP-RING finger found in the Siz/PIAS RING (SP-RING) family of SUMO E3 ligases and SPL-RING finger found in E3 SUMO-protein ligase NSE2. The SP-RING family includes PIAS (protein inhibitor of activated STAT) proteins, Zmiz proteins, and Siz proteins from plants and fungi. The PIAS (protein inhibitor of activated STAT) protein family modulates the activity of several transcription factors and acts as an E3 ubiquitin ligase in the sumoylation pathway. NSE2, also known as MMS21 homolog (MMS21) or non-structural maintenance of chromosomes element 2 homolog (Non-SMC element 2 homolog, NSMCE2), is an autosumoylating small ubiquitin-like modifier (SUMO) ligase required for the response to DNA damage. It regulates sumoylation and nuclear-to-cytoplasmic translocation of skeletal and heart muscle-specific variant of the alpha subunit of nascent polypeptide associated complex (skNAC)-Smyd1 in myogenesis. It is also required for resisting extrinsically induced genotoxic stress.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 21361539  18 CPVCQEVLKTPVRTTACQHVFCRKCFLTAMRESG--AHCPLCR 58
Cdd:cd16452   3 CPITQKRMKDPVRGKHCGHCFDLEAILQYLKRRKkkWKCPVCS 45

RING finger, HC subclass, found in tripartite motif-containing protein 26 (TRIM26) and similar proteins; TRIM26, also known as acid finger protein (AFP), RING finger protein 95 (RNF95), or zinc finger protein 173 (ZNF173), is an E3 ubiquitin-protein ligase that negatively regulates interferon-beta production and antiviral response through polyubiquitination and degradation of nuclear transcription factor IRF3. It functions as an important regulator for RNA virus-triggered innate immune response by bridging TBK1 to NEMO (NF-kappaB essential modulator, also known as IKKgamma) and mediating TBK1 activation. It also acts as a novel tumor suppressor of hepatocellular carcinoma by regulating cancer cell proliferation, colony forming ability, migration, and invasion. TRIM26 belongs the C-IV subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, a B-box, and two coiled coil domains, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 21361539  13 EDDFYCPVCQEVLKTPVrTTACQHVFCRKCFLTAMRESGAH----CPLCRG 59
Cdd:cd16598   2 EEEVTCSICLDYLRDPV-TIDCGHNFCRSCITDYCPISGGHerpvCPLCRK 51

RING finger, HC subclass, found in RING finger and transmembrane domain-containing protein RNFT1, RNFT2, and similar proteins; Both RNFT1 and RNFT2 are multi-pass membrane proteins containing a C3HC4-type RING-HC finger. Their biological roles remain unclear.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|..
gi 21361539  18 CPVCQEVLKTPVRTTaCQHVFCRKCFLTAM-RESGahCPLCR 58
Cdd:cd16532   3 CPICQDEFKDPVVLR-CKHIFCEDCVSEWFeRERT--CPLCR 41

Ring finger domain;

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|...
gi 21361539    18 CPVCQEVLKTP--VRTTACQHVFCRKCFLTAMRESGaHCPLCR 58
Cdd:pfam13639   3 CPICLEEFEEGdkVVVLPCGHHFHRECLDKWLRSSN-TCPLCR 44

RING finger, HC subclass, found in Equid alphaherpesvirus 1 (Equine herpesvirus 1/EHV-1) regulatory protein and similar proteins; EHV-1 regulatory protein belongs to the Vmw110 (IPC0) protein family. It contains a typical C3HC4-type RING-HC finger and binds zinc stably.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 21361539  16 FYCPVCQEVLKTPVRTTACQHVFCRKCFLTAMRESgAHCPLCRGNVTR 63
Cdd:cd23130   1 DVCPICLDDPEDEAITLPCLHQFCYTCILRWLQTS-PTCPLCKTPVTS 47

RING finger, HC subclass, found in tripartite motif-containing proteins, TRIM7, TRIM11 and TRIM27, and similar proteins; TRIM7, TRIM11 and TRIM27, closely related tripartite motif-containing proteins, belong to the C-IV subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox2, and a coiled coil region, as well as a SPRY/B30.2 domain positioned C-terminal to the RBCC domain. TRIM7, also known as glycogenin-interacting protein (GNIP) or RING finger protein 90 (RNF90), is an E3 ubiquitin-protein ligase that mediates c-Jun/AP-1 activation by Ras signalling. Its phosphorylation and activation by MSK1 in response to direct activation by the Ras-Raf-MEK-ERK pathway can stimulate TRIM7 E3 ubiquitin ligase activity in mediating Lys63-linked ubiquitination of the AP-1 coactivator RACO-1, leading to RACO-1 protein stabilization. Moreover, TRIM7 binds and activates glycogenin, the self-glucosylating initiator of glycogen biosynthesis. TRIM11, also known as protein BIA1, or RING finger protein 92 (RNF92), is an E3 ubiquitin-protein ligase involved in the development of the central nervous system. It is overexpressed in high-grade gliomas and promotes proliferation, invasion, migration and glial tumor growth. TRIM11 acts as a potential therapeutic target for congenital central hypoventilation syndrome (CCHS) by mediating the degradation of CCHS-associated polyalanine-expanded Phox2b. TRIM11 modulates the function of neurogenic transcription factor Pax6 through the ubiquitin-proteosome system, and thus plays an essential role for Pax6-dependent neurogenesis. It also binds to and destabilizes a key component of the activator-mediated cofactor complex (ARC105), humanin, a neuroprotective peptide against Alzheimer's disease-relevant insults, and further regulates ARC105 function in transforming growth factor beta (TGFbeta) signaling. Moreover, TRIM11 negatively regulates retinoic acid-inducible gene-I (RIG-I)-mediated interferon-beta (IFNbeta) production and antiviral activity by targeting TANK-binding kinase-1 (TBK1). It may contribute to the endogenous restriction of retroviruses in cells. It enhances N-tropic murine leukemia virus (N-MLV) entry by interfering with Ref1 restriction. It also suppresses the early steps of human immunodeficiency virus HIV-1 transduction, resulting in decreased reverse transcripts. TRIM27, also known as RING finger protein 76 (RNF76), RET finger protein (RFP), or zinc finger protein RFP, is a nuclear E3 ubiquitin-protein ligase that is highly expressed in testis and in various tumor cell lines. Expression of TRIM27 is associated with prognosis of colon and endometrial cancers. TRIM27 was first identified as a fusion partner of the RET receptor tyrosine kinase. It functions as a transcriptional repressor and associates with several proteins involved in transcriptional activity, such as enhancer of polycomb 1 (Epc1), a member of the Polycomb group proteins, and Mi-2beta, a main component of the nucleosome remodeling and deacetylase (NuRD) complex, and the cell cycle regulator retinoblastoma protein (RB1). It also interacts with HDAC1, leading to downregulation of thioredoxin binding protein 2 (TBP-2), which inhibits the function of thioredoxin. Moreover, TRIM27 mediates Pax7-induced ubiquitination of MyoD in skeletal muscle atrophy. In addition, it inhibits muscle differentiation by modulating serum response factor (SRF) and Epc1. TRIM27 promotes a non-canonical polyubiquitination of PTEN, a lipid phosphatase that catalyzes PtdIns(3,4,5)P3 (PIP3) to PtdIns(4,5)P2 (PIP2). It is an IKKepsilon-interacting protein that regulates IkappaB kinase (IKK) function and negatively regulates signaling involved in the antiviral response and inflammation. TRIM27 also forms a protein complex with MBD4 or MBD2 or MBD3, and thus plays an important role in the enhancement of transcriptional repression through MBD proteins in tumorigenesis, spermatogenesis, and embryogenesis. It is a component of an estrogen receptor 1 (ESR1) regulatory complex that is involved in estrogen receptor-mediated transcription in MCF-7 cells.

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                ....*....|....*....|....*....|....*....|....*....|....*.
gi 21361539  14 DDFYCPVCQEVLKTPVrTTACQHVFCRKCFLTAMRESG--AHCPLCRGNVTRRERA 67
Cdd:cd16594   4 EELTCPICLDYFTDPV-TLDCGHSFCRACIARCWEEPEtsASCPQCRETCPQRNLR 58

RING finger, HC subclass, found in ubiquitin-like PHD and RING finger domain-containing protein 2 (UHRF2); UHRF2, also known as Np95/ICBP90-like RING finger protein (NIRF), Np95-like RING finger protein, nuclear protein 97, nuclear zinc finger protein Np97, RING finger protein 107, or E3 ubiquitin-protein ligase UHRF2, was originally identified as a ubiquitin ligase acting as a small ubiquitin-like modifier (SUMO) E3 ligase that enhances zinc finger protein 131 (ZNF131) SUMOylation, but does not enhance ZNF131 ubiquitination. It also ubiquitinates PCNP, a PEST-containing nuclear protein. Moreover, UHRF2 functions as a nuclear protein involved in cell-cycle regulation and has been implicated in tumorigenesis. It interacts with cyclins, CDKs, p53, pRB, PCNA, HDAC1, DNMTs, G9a, methylated histone H3 lysine 9, and methylated DNA. It interacts with the cyclin E-CDK2 complex, ubiquitinates cyclins D1 and E1, induces G1 arrest, and is involved in the G1/S transition regulation. Furthermore, UHRF2 is a direct transcriptional target of the transcription factor E2F-1 in the induction of apoptosis. It recruits HDAC1 and binds to methyl-CpG. UHRF2 also participates in the maturation of Hepatitis B virus (HBV) through interacting with HBV core protein and promoting its degradation. UHRF2 contains an N-terminal ubiquitin-like domain (UBL), a tandem Tudor domain (TTD), a plant homeodomain (PHD) domain, a SET- and RING-associated (SRA) domain, and a C-terminal C3HC4-type RING-HC finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*.
gi 21361539  13 EDDFYCPVCQEVLKTPVrTTACQHVFCRKCFLTAMRESGAHCPLCR 58
Cdd:cd16770   1 EESFLCICCQELVYQPV-TTECQHNVCKSCLQRSFKAEVYTCPACR 45

RING finger, HC subclass, found in tripartite motif-containing protein 72 (TRIM72) and similar proteins; TRIM72, also known as Mitsugumin-53 (MG53), is a muscle-specific protein that plays a central role in cell membrane repair by nucleating the assembly of the repair machinery at muscle injury sites. It is required in repair of alveolar epithelial cells under plasma membrane stress failure. It interacts with dysferlin to regulate sarcolemmal repair. Upregulation of TRIM72 develops obesity, systemic insulin resistance, dyslipidemia, and hyperglycemia, as well as induces diabetic cardiomyopathy through transcriptional activation of the peroxisome proliferation-activated receptor alpha (PPAR-alpha) signaling pathway. Compensation for the absence of AKT signaling by ERK signaling during TRIM72 overexpression leads to pathological hypertrophy. Moreover, TRIM72 functions as a novel negative feedback regulator of myogenesis by targeting insulin receptor substrate-1 (IRS-1). It is transcriptionally activated by the synergism of myogenin (MyoD) and myocyte enhancer factor 2 (MEF2). TRIM72 belongs to the C-IV subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain.

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                ....*....|....*....|....*....|....*....|....*....|....*..
gi 21361539  15 DFYCPVCQEVLKTPVrTTACQHVFCRKCFLTAMRE---SGAHCPLCRGnVTRRERAC 68
Cdd:cd16612   4 DLSCPLCLKLFQSPV-TTECGHTFCQDCLSRVPKEedgGSTSCPTCQA-PTKPEQLS 58

Modified RING finger, HC subclass (C3HC3D-type), found in tumor necrosis factor (TNF) receptor-associated factor 7 (TRAF7) and similar proteins; TRAF7, also known as RING finger and WD repeat-containing protein 1 or RING finger protein 119 (RNF119), is an E3 ubiquitin-protein ligase involved in signal transduction pathways that lead either to activation or repression of NF-kappaB transcription factor by promoting K29-linked ubiquitination of several cellular targets, including the NF-kappaB essential modulator (NEMO) and the p65 subunit of NF-kappaB transcription factor. It is also involved in K29-linked polyubiquitination that has been implicated in lysosomal degradation of proteins. Moreover, TRAF7 is required for K48-linked ubiquitination of p53, a key tumor suppressor and a master regulator of various signaling pathways, such as those related to apoptosis, cell cycle and DNA repair. It is also required for tumor necrosis factor alpha (TNFalpha)-induced Jun N-terminal kinase activation and promotes cell death by regulating polyubiquitination and lysosomal degradation of c-FLIP protein. Furthermore, TRAF7 functions as small ubiquitin-like modifier (SUMO) E3 ligase involved in other post-translational modification, such as sumoylation. It binds to and stimulates sumoylation of the proto-oncogene product c-Myb, a transcription factor regulating proliferation and differentiation of hematopoietic cells. It potentiates MEKK3-induced AP1 and CHOP activation and induces apoptosis. Meanwhile, TRAF7 mediates MyoD1 regulation of the pathway and cell-cycle progression in myoblasts. It also plays a role in Toll-like receptors (TLR) signaling. TRAF7 contains an N-terminal domain with a modified C3HC3D-type RING-HC finger and an adjacent zinc finger, and a unique C-terminal domain that comprises a coiled coil domain and seven WD40 repeats.

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                ....*....|....*....|....*....|....*....|
gi 21361539  17 YCPVCQEVLKTPVrTTACQHVFCRKCFLTAMRESgahCPL 56
Cdd:cd16644   7 YCPLCQRVFKDPV-ITSCGHTFCRRCALTAPGEK---CPV 42

RING finger, HC subclass, found in tripartite motif-containing protein TRIM21 and similar proteins; TRIM21, also known as 52 kDa Ro protein, 52 kDa ribonucleoprotein autoantigen Ro/SS-A, Ro(SS-A), RING finger protein 81 (RNF81), or Sjoegren syndrome type A antigen (SS-A), is a ubiquitously expressed E3 ubiquitin-protein ligase and a high affinity antibody receptor uniquely expressed in the cytosol of mammalian cells. As a cytosolic Fc receptor, TRIM21 binds the Fc of virus-associated antibodies and targets the complex in the cytosol for proteasomal degradation in a process known as antibody-dependent intracellular neutralization (ADIN), and provides an intracellular immune response to protect host defense against pathogen infection. It shows remarkably broad isotype specificity as it does not only bind IgG, but also IgM and IgA. Moreover, TRIM21 promotes the cytosolic DNA sensor cGAS and the cytosolic RNA sensor RIG-I sensing of viral genomes during infection by antibody-opsonized virus. It stimulates inflammatory signaling and activates innate transcription factors, such as nuclear factor-kappaB (NF-kappaB). TRIM21 also plays an essential role in p62-regulated redox homeostasis, suggesting it may be a viable target for treating pathological conditions resulting from oxidative damage. Furthermore, TRIM21 may have implications for various autoimmune diseases associated with uncontrolled antiviral signaling through the regulation of Nmi-IFI35 complex-mediated inhibition of innate antiviral response. TRIM21 belongs to the C-IV subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|.
gi 21361539  18 CPVCQEVLKTPVrTTACQHVFCRKCFLTAMRESGAHCPLCR 58
Cdd:cd16596  12 CPICLDPFVEPV-SIECGHSFCQECISQVGKGGGSVCPVCR 51

RING finger, HC subclass, found in tripartite motif-containing protein 10 (TRIM10) and similar proteins; TRIM10, also known as B30-RING finger protein (RFB30), RING finger protein 9 (RNF9), or hematopoietic RING finger 1 (HERF1), is a novel hematopoiesis-specific RING finger protein required for terminal differentiation of erythroid cells. TRIM10 belongs to the C-IV subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain.

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                ....*....|....*....|....*....|....*....|....*....|.
gi 21361539  14 DDFYCPVCQEVLKTPVrTTACQHVFCRKCFLTAMRESGAH------CPLCR 58
Cdd:cd16593   4 DEVNCPICQGTLREPV-TIDCGHNFCRACLTRYCEIPGPDleepptCPLCK 53

Modified RING finger, C3HGC3-type, found in RING finger and WD repeat domain-containing protein 3 (RFWD3) and similar proteins; RFWD3, also known as RING finger protein 201 (RNF201) or FLJ10520, is an E3 ubiquitin-protein ligase that forms a complex with Mdm2 and p53 to synergistically ubiquitinate p53 and acts as a positive regulator of p53 stability in response to DNA damage. It is phosphorylated by checkpoint kinase ATM/ATR and the phosphorylation mutant fails to stimulate p53 ubiquitination. RFWD3 also functions as a novel replication protein A (RPA)-associated protein involved in DNA replication checkpoint control. RFWD3 contains an N-terminal SQ-rich region followed by a RING finger domain that exhibits robust E3 ubiquitin ligase activity toward p53, a coiled-coil domain and three WD40 repeats in the C-terminus, the latter two of which may be responsible for protein-protein interaction. The RING finger in this family is a modified C3HGC3-type RING finger, but not a canonical C3H2C3-type RING-H2 finger or C3HC4-type RING-HC finger.

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                ....*....|....*....|....*....|....*....|....*....|....*.
gi 21361539  14 DDFYCPVCQEVLKTP----VRTTACQHVFCRKCFLTAMRESGAHCPLCRGNVTRRE 65
Cdd:cd16450   1 EGNTCPICFEPWTSSgehrLVSLKCGHLFGYSCIEKWLKGKGKKCPQCNKKAKRSD 56

Uncharacterized conserved protein, contains RING and CCCH-type Zn-fingers [General function prediction only];

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                ....*....|....*....|....*....|....*....|..
gi 21361539  16 FYCPVCQEVLKTPVRTTaCQHVFCRKCFLTAMREsGAHCPLC 57
Cdd:COG5152 197 FLCGICKKDYESPVVTE-CGHSFCSLCAIRKYQK-GDECGVC 236

RING finger, HC subclass, found in constitutive photomorphogenesis protein 1 (COP1) and similar proteins; COP1, also known as RING finger and WD repeat domain protein 2 (RFWD2) or RING finger protein 200 (RNF200), is a central regulator of photomorphogenic development in plants, which targets key transcription factors for proteasome-dependent degradation. It is localized predominantly in the nucleus, but may also be present in the cytosol. Mammalian COP1 functions as an E3 ubiquitin-protein ligase that interacts with Jun transcription factors and modulates their transcriptional activity. It also interacts with and negatively regulates the tumor-suppressor protein p53. Moreover, COP1 associates with COP9 signalosome subunit 6 (CSN6), and is involved in 14-3-3sigma ubiquitin-mediated degradation. The CSN6-COP1 link enhances ubiquitin-mediated degradation of p27(Kip1), a critical CDK inhibitor involved in cell cycle regulation, to promote cancer cell growth. Furthermore, COP1 functions as the negative regulator of ETV1 and influences prognosis in triple-negative breast cancer. COP1 contains an N-terminal extension, a C3HC4-type RING-HC finger, a coiled coil domain, and seven WD40 repeats. In human COP1, a classic leucine-rich NES, and a novel bipartite NLS is bridged by the RING-HC finger.

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                ....*....|....*....|....*....|....*....|....
gi 21361539  14 DDFYCPVCQEVLKTPVrTTACQHVFCRKCFLTAMRESgAHCPLC 57
Cdd:cd16504   1 NDFLCPICFDIIKEAF-VTKCGHSFCYKCIVKHLEQK-NRCPKC 42

RING finger, HC subclass, found in tripartite motif-containing protein 35 (TRIM35) and similar proteins; TRIM35, also known as hemopoietic lineage switch protein 5 (HLS5), is a putative hepatocellular carcinoma (HCC) suppressor that inhibits phosphorylation of pyruvate kinase isoform M2 (PKM2), which is involved in aerobic glycolysis of cancer cells and further suppresses the Warburg effect and tumorigenicity in HCC. It also negatively regulates Toll-like receptor 7 (TLR7)- and TLR9-mediated type I interferon production by suppressing the stability of interferon regulatory factor 7 (IRF7). Moreover, TRIM35 regulates erythroid differentiation by modulating globin transcription factor 1 (GATA-1) activity. TRIM35 belongs to the C-IV subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain.

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                ....*....|....*....|....*....|....*....|....*....|....
gi 21361539  13 EDDFYCPVCQEVLKTPVrTTACQHVFCRKCF-LTAMRESGAHCPLCRGNVTRRE 65
Cdd:cd16599   2 KEELLCPICYEPFREAV-TLRCGHNFCKGCVsRSWERQPRAPCPVCKEASSSDD 54

RING finger, HC subclass, found in RING finger proteins RNF113A, RNF113B, and similar proteins; RNF113A, also known as zinc finger protein 183 (ZNF183), is an E3 ubiquitin-protein ligase that physically interacts with the E2 protein, UBE2U. A nonsense mutation in RNF113A is associated with an X-linked trichothiodystrophy (TTD). Its yeast ortholog Cwc24p is predicted to have a spliceosome function and acts in a complex with Cef1p to participate in pre-U3 snoRNA splicing, indirectly affecting pre-rRNA processing. It is also important for the U2 snRNP binding to primary transcripts and co-migrates with spliceosomes. Moreover, the ortholog of RNF113A in fruit flies may also act as a spliceosome and is hypothesized to be involved in splicing, namely within the central nervous system. The ortholog in Caenorhabditis elegans is involved in DNA repair of inter-strand crosslinks. RNF113B, also known as zinc finger protein 183-like 1, shows high sequence similarity with RNF113A. Both RNF113A and RNF113B contain a CCCH-type zinc finger, which is commonly found in RNA-binding proteins involved in splicing, and a C3HC4-type RING-HC finger, which is frequently found in E3 ubiquitin ligases.

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                ....*....|....*....|....*....|....*....|...
gi 21361539  16 FYCPVCQEVLKTPVRTTaCQHVFCRKCFLTAMRESGaHCPLCR 58
Cdd:cd16539   6 FACFICRKPFKNPVVTK-CGHYFCEKCALKHYRKSK-KCFVCG 46

RING finger, HC subclass, found in E3 ubiquitin-protein ligase Deltex3 (DTX3), Deltex-3-like (DTX3L) and similar proteins; This subfamily contains Deltex3 (DTX3) and Deltex-3-like (DTX3L), both of which are E3 ubiquitin-protein ligases belonging to the Deltex (DTX) family. DTX3, also known as RING finger protein 154 (RNF154), has a biological function that remains unclear. DTX3L, also known as B-lymphoma- and BAL-associated protein (BBAP) or Rhysin-2 (Rhysin2), regulates endosomal sorting of the G protein-coupled receptor CXCR4 from endosomes to lysosomes. It also regulates subcellular localization of its partner protein, B aggressive lymphoma (BAL), by a dynamic nucleocytoplasmic trafficking mechanism. In contrast to other DTXs, both DTX3 and DTX3L contain a C3HC4-type RING-HC finger, and a previously unidentified C-terminal domain. DTX3L can associate with DTX1 through its unique N termini and further enhance self-ubiquitination.

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                ....*....|....*....|....*....|....*....|.
gi 21361539  18 CPVCQEVLKTPVRTTACQHVFCRKCFLTAMRESGAhCPLCR 58
Cdd:cd16506   3 CPICLDEIQNKKTLEKCKHSFCEDCIDRALQVKPV-CPVCG 42

RING finger, HC subclass, found in ubiquitin-like PHD and RING finger domain-containing proteins, UHRF1 and UHRF2, and similar proteins; UHRF1 is a unique chromatin effector protein that integrates the recognition of both histone PTMs and DNA methylation. It is essential for cell proliferation and plays a critical role in the development and progression of many human carcinomas, such as laryngeal squamous cell carcinoma (LSCC), gastric cancer (GC), esophageal squamous cell carcinoma (ESCC), colorectal cancer, prostate cancer, and breast cancer. UHRF1 acts as a transcriptional repressor through its binding to histone H3 when it is unmodified at Arg2. Its overexpression in human lung fibroblasts results in downregulation of expression of the tumor suppressor pRB. It also plays a role in transcriptional repression of the cell cycle regulator p21. Moreover, UHRF1-dependent repression of transcription factors can facilitate the G1-S transition. It interacts with Tat-interacting protein of 60 kDa (TIP60) and induces degradation-independent ubiquitination of TIP60. It is also an N-methylpurine DNA glycosylase (MPG)-interacting protein that binds MPG in a p53 status-independent manner in the DNA base excision repair (BER) pathway. In addition, UHRF1 functions as an epigenetic regulator that is important for multiple aspects of epigenetic regulation, including maintenance of DNA methylation patterns and recognition of various histone modifications. UHRF2 was originally identified as a ubiquitin ligase acting as a small ubiquitin-like modifier (SUMO) E3 ligase that enhances zinc finger protein 131 (ZNF131) SUMOylation, but does not enhance ZNF131 ubiquitination. It also ubiquitinates PCNP, a PEST-containing nuclear protein. Moreover, UHRF2 functions as a nuclear protein involved in cell-cycle regulation and has been implicated in tumorigenesis. It interacts with cyclins, CDKs, p53, pRB, PCNA, HDAC1, DNMTs, G9a, methylated histone H3 lysine 9, and methylated DNA. It interacts with the cyclin E-CDK2 complex, ubiquitinates cyclins D1 and E1, induces G1 arrest, and is involved in the G1/S transition regulation. Furthermore, UHRF2 is a direct transcriptional target of the transcription factor E2F-1 in the induction of apoptosis. It recruits HDAC1 and binds to methyl-CpG. UHRF2 also participates in the maturation of Hepatitis B virus (HBV) by interacting with the HBV core protein and promoting its degradation. Both UHRF1 and UHRF2 contain an N-terminal ubiquitin-like domain (UBL), a tandem Tudor domain (TTD), a plant homeodomain (PHD) finger, a SET- and RING-associated (SRA) domain, and a C-terminal C3HC4-type RING-HC finger.

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                ....*....|....*....|....*....|....*....|...
gi 21361539  16 FYCPVCQEVLKTPVrTTACQHVFCRKCFLTAMRESGAHCPLCR 58
Cdd:cd16613   1 FTCICCQELVYKPI-TTPCKHNICKSCLQRSFKAEVYTCPACR 42

first RING finger, HC subclass, found in the LON peptidase N-terminal domain and RING finger protein family; The LON peptidase N-terminal domain and RING finger protein family includes LONRF1 (also known as RING finger protein 191 or RNF191), LONRF2 (also known as RING finger protein 192, RNF192, or neuroblastoma apoptosis-related protease), LONRF3 (also known as RING finger protein 127 or RNF127), which are characterized by containing two C3HC4-type RING-HC fingers, four tetratricopeptide (TPR) repeats, and an ATP-dependent protease La (LON) substrate-binding domain at the C-terminus. Their biological functions remain unclear. This model corresponds to the first RING-HC finger.

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gi 21361539  14 DDFYCPVCQEVLKTPVrTTACQHVFCRKCFltaMRESGAHCPLCR 58
Cdd:cd16513   1 DLLSCPLCRGLLFEPV-TLPCGHTFCKRCL---ERDPSSRCRLCR 41

RING finger, HC subclass, found in SH3 domain-containing RING finger proteins SH3RF1, SH3RF2, SH3RF3, and similar proteins; SH3RF1, also known as plenty of SH3s (POSH), RING finger protein 142 (RNF142), or SH3 multiple domains protein 2 (SH3MD2), is a trans-Golgi network-associated pro-apoptotic scaffold protein with E3 ubiquitin-protein ligase activity. SH3RF2, also known as heart protein phosphatase 1-binding protein (HEPP1), plenty of SH3s (POSH)-eliminating RING protein (POSHER), protein phosphatase 1 regulatory subunit 39, or RING finger protein 158 (RNF158), is a putative E3 ubiquitin-protein ligase that acts as an anti-apoptotic regulator for the c-Jun N-terminal kinase (JNK) pathway by binding to and promoting the proteasomal degradation of SH3RF1 (or POSH) that is required for pro-apoptotic JNK activation. SH3RF3, also known as plenty of SH3s 2 (POSH2) or SH3 multiple domains protein 4 (SH3MD4), is a scaffold protein with E3 ubiquitin-protein ligase activity. It was identified in the screen for interacting partners of p21-activated kinase 2 (PAK2) and may play a role in regulating c-Jun N-terminal kinase (JNK) mediated apoptosis in certain conditions. Members of this subfamily contain an N-terminal C3HC4-type RING-HC finger responsible for the E3 ligase activity and four Src Homology 3 (SH3) domains, which are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs.

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                ....*....|....*....|....*....|....*....|..
gi 21361539  18 CPVCQEVLKTPVRTTACQHVFCRKCFLTAMRESGA-HCPLCR 58
Cdd:cd16570   3 CPVCLERLDVSAKVLPCQHTFCKRCLQIIVASRGElRCPECR 44

RING finger, HC subclass, found in muscle-specific RING finger protein 1 (MuRF-1) and similar proteins; MuRF-1, also known as tripartite motif-containing protein 63 (TRIM63), RING finger protein 28 (RNF28), iris RING finger protein, or striated muscle RING zinc finger, is an E3 ubiquitin-protein ligase in ubiquitin-mediated muscle protein turnover. It is predominantly fast (type II) fibre-associated in skeletal muscle and can bind to many myofibrillar proteins, including titin, nebulin, the nebulin-related protein NRAP, troponin-I (TnI), troponin-T (TnT), myosin light chain 2 (MLC-2), myotilin, and T-cap. The early and robust upregulation of MuRF-1 is triggered by disuse, denervation, starvation, sepsis, or steroid administration resulting in skeletal muscle atrophy. It also plays a role in maintaining titin M-line integrity. It associates with the periphery of the M-line lattice and may be involved in the regulation of the titin kinase domain. It also participates in muscle stress response pathways and gene expression. MuRF-1 belongs to the C-II subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox2, and a coiled coil region, as well as a COS (carboxyl-terminal subgroup one signature) box, and an acidic residue-rich (AR) domain. It also harbors a MURF family-specific conserved box (MFC) between its RING-HC finger and Bbox domains.

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                ....*....|....*....|....*....|
gi 21361539  13 EDDFYCPVCQEVLKTPVRTTACQHVFCRKC 42
Cdd:cd16759   1 EKQLICPICLEMFTKPVVILPCQHNLCRKC 30

Modified RING finger, HC subclass (C3HC3D-type), found in tumor necrosis factor (TNF) receptor-associated factor 4 (TRAF4) and similar proteins; TRAF4, also known as cysteine-rich domain associated with RING and Traf domains protein 1, metastatic lymph node gene 62 protein (MLN 62), or RING finger protein 83 (RNF83), is a member of the TRAF protein family, which mainly function in the immune system, where they mediate signaling through tumor necrosis factor receptors (TNFRs) and interleukin-1/Toll-like receptors (IL-1/TLRs). It also plays a critical role in nervous system, as well as in carcinogenesis. TRAF4 promotes the growth and invasion of colon cancer through the Wnt/beta-catenin pathway. It contributes to the TNFalpha-induced activation of the 70 kDa ribosomal protein S6 kinase (p70s6k) signaling pathway, and activation of transforming growth factor beta (TGF-beta)-induced SMAD-dependent signaling and non-SMAD signaling in breast cancer. It also enhances osteosarcoma cell proliferation and invasion by the Akt signaling pathway. Moreover, TRAF4 is a novel phosphoinositide-binding protein modulating tight junctions and favoring cell migration. TRAF4 contains an N-terminal domain with a modified C3HC3D-type RING-HC finger and several zinc fingers, and a C-terminal TRAF domain that comprises a coiled coil domain and a conserved TRAF-C domain.

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                ....*....|....*....|....*....|....*....|
gi 21361539  16 FYCPVCQEVLKTPVRTTACQHVFCRKCFLTAMRESGAHCP 55
Cdd:cd16641   2 LLCPLCRLPMREPVQISTCGHRFCDTCLQEFLSEGVFKCP 41

RING finger, HC subclass, found in tripartite motif-containing protein 59 (TRIM59) and similar proteins; TRIM59, also known as RING finger protein 104 (RNF104) or tumor suppressor TSBF-1, is a putative E3 ubiquitin-protein ligase that functions as a novel multiple cancer biomarker for immunohistochemical detection of early tumorigenesis. It is upregulated in gastric cancer and promotes gastric carcinogenesis by interacting with and targeting the P53 tumor suppressor for its ubiquitination and degradation. It also acts as a novel accessory molecule involved in cytotoxicity of BCG-activated macrophages (BAM). Moreover, TRIM59 may serve as a multifunctional regulator for innate immune signaling pathways. It interacts with ECSIT and negatively regulates nuclear factor-kappaB (NF- kappa B) and interferon regulatory factor (IRF)-3/7-mediated signal pathways. TRIM59 belongs to the C-V subclass of the TRIM (tripartite motif) family of proteins that are defined by an N-terminal RBCC (RING, Bbox, and coiled coil) domain, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region. In addition, TRIM59 contains a C-terminal transmembrane domain.

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gi 21361539  13 EDDFYCPVCQEVLKTPvRTTACQHVFCRKCFLTAMRESG-----------AHCPLCR 58
Cdd:cd16763   1 EEDLTCSVCYSLFEDP-RVLPCSHTFCRNCLENILQVSGnfsiwrplrppLKCPNCR 56

RING finger, HC subclass, found in RING finger and transmembrane domain-containing protein 1 (RNFT1); RNFT1, also known as protein PTD016, is a multi-pass membrane protein containing a C3HC4-type RING-HC finger. Its biological role remains unclear.

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gi 21361539  12 TEDDFYCPVCQEVLKTPVRTTaCQHVFCRKCfLTAMRESGAHCPLCR 58
Cdd:cd16741  11 SEADDICAICQAEFRKPILLI-CQHVFCEEC-ISLWFNREKTCPLCR 55

Modified RING finger, HC subclass (C3HC3D-type), found in neuregulin receptor degradation protein-1 (Nrdp1) and similar proteins; Nrdp1 (referred to as FLRF in mice), also known as RING finger protein 41 (RNF41), is an E3 ubiquitin-protein ligase that plays a critical role in the regulation of cell growth and apoptosis, inflammation and production of reactive oxygen species (ROS), as well as in doxorubicin (DOX)-induced cardiac injury. It promotes the degradation of the epidermal growth factor receptor (EGFR/ErbB) family member, ErbB3, which is independent of growth factor stimulation. It also promotes M2 macrophage polarization by ubiquitinating and activating transcription factor CCAAT/enhancer-binding protein beta (C/EBPbeta) via Lys-63-linked ubiquitination. Moreover, Nrdp1 interacts with and modulates the activity of Parkin, a causative protein for early onset recessive juvenile parkinsonism (AR-JP). It also interacts with ubiquitin-specific protease 8 (USP8), which is involved in trafficking of various transmembrane proteins. Furthermore, Nrdp1 inhibits basal lysosomal degradation and enhances ectodomain shedding of JAK2-associated cytokine receptors. Its phosphorylation by the kinase Par-1b (also known as MARK2) is required for epithelial cell polarity. Nrdp1 contains an N-terminal modified C3HC3D-type RING-HC finger required for enhancing ErbB3 degradation, a B-box, a coiled-coil domain responsible for Nrdp1 oligomerization, and a C-terminal ErbB3-binding domain.

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gi 21361539  15 DFYCPVCQEVLKTPVRTTACQHVFCRKC 42
Cdd:cd16634   1 ELICPICSGVLEEPLQAPHCEHAFCNAC 28

Modified RING finger, HC subclass (C3HC3D-type), found in tumor necrosis factor (TNF) receptor-associated factor 5 (TRAF5) and similar proteins; TRAF5, also known as RING finger protein 84 (RNF84), is an important signal transducer for a wide range of TNF receptor superfamily members, including tumor necrosis factor receptor 1 (TNFR1), TNFR2, CD40, and other lymphocyte costimulatory receptors, RANK/TRANCE-R, ectodysplasin-A Receptor (EDAR), lymphotoxin-beta receptor (LT-betaR), latent membrane protein 1 (LMP1), and IRE1. It functions as an activator of NF-kappaB, MAPK, and JNK, and is involved in both RANKL- and TNFalpha-induced osteoclastogenesis. It mediates CD40 signaling by associating with the cytoplasmic tail of CD40. It also negatively regulates Toll-like receptor (TLR) signaling and functions as a negative regulator of the interleukin 6 (IL-6) receptor signaling pathway that limits the differentiation of inflammatory CD4(+) T cells. TRAF5 contains an N-terminal domain with a modified C3HC3D-type RING-HC finger and several zinc fingers, and a C-terminal TRAF domain that comprises a coiled coil domain and a conserved TRAF-C domain.

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gi 21361539  13 EDDFYCPVCQEVLKTPvRTTACQHVFCRKCFLTAMRESG-AHCPLCRGNVTRRE 65
Cdd:cd16642   2 EDRYKCATCHFVLHNP-HQTGCGHRFCQHCILSLLELNTtPICPIDKETIKSDE 54