RING finger (Really Interesting New Gene) domain and U-box domain superfamily; 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). C4C4-, C3HC3D-, C2H2C4-, and C3HC5-type RING fingers are closely related to RING-HC fingers. In contrast, C4HC3- (RING-CH alias RINGv), C3H3C2-, C3H2C2D-, C3DHC3-, and C4HC2H-type RING fingers are more closely related to RING-H2 fingers. However, not all RING finger-containing proteins display regular RING finger features, and the RING finger family has turned out to be multifarious. The degenerate RING fingers of the Siz/PIAS RING (SP-RING) family proteins and sporulation protein RMD5, are characterized by lacking the second, fifth, and sixth Zn2+ ion-coordinating residues. They bind only one Zn2+ ion. On the other hand, the RING fingers of the human APC11 and RBX1 proteins can bind a third Zn atom since they harbor four additional Zn ligands. U-box is a modified form of the RING finger domain that lacks metal chelating Cys and His residues. It resembles the cross-brace RING structure consisting of three beta-sheets and a single alpha-helix, which would be stabilized by salt bridges instead of chelated metal ions. U-box proteins are widely distributed among eukaryotic organisms and show a higher prevalence in plants than in other organisms. RING finger/U-box-containing proteins are 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 enable efficient transfer of ubiquitin from E2 to the substrates.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 24584571  96 ENSTCSICLLPWTDNGIHRLVSLRCGHLFGSSCIHMAI-RRNHRCPICRRRARHFHVRRIY 155
Cdd:cd16450   1 EGNTCPICFEPWTSSGEHRLVSLKCGHLFGYSCIEKWLkGKGKKCPQCNKKAKRSDIRPLY 61

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.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 24584571  96 ENSTCSICLLPWTDNGIHRLVSLRCGHLFGSSCIHMAI-RRNHRCPICRRRARHFHVRRIY 155
Cdd:cd16450   1 EGNTCPICFEPWTSSGEHRLVSLKCGHLFGYSCIEKWLkGKGKKCPQCNKKAKRSDIRPLY 61

HRD ubiquitin ligase complex, ER membrane component [Posttranslational modification, protein turnover, chaperones];

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 24584571  36 HNLRVKHLNTQRRRILR-LLQGKMLQYATLEERLHRiGELVLIAELHSGVKTL------NQRLDRMVENST--------- 99
Cdd:COG5243 210 YLFRLEVCYDGLTLLAYsLLFMYQFPYVRVPIYLIR-QMYTCFYALFRRIREHarfrraTKDLNAMYPTATeeqltnsdr 288

                        90       100       110       120       130
                ....*....|....*....|....*....|....*....|....*....|....
gi 24584571 100 -CSICL--------LPWTDNGIHRLVSLRCGHLFGSSCIHMAIRRNHRCPICRR 144
Cdd:COG5243 289 tCTICMdemfhpdhEPLPRGLDMTPKRLPCGHILHLHCLKNWLERQQTCPICRR 342

RING-finger-containing E3 ubiquitin ligase [Posttranslational modification, protein turnover, chaperones];

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 24584571 100 CSICLLPwtdngIHRLVSLRCGHLFGSSCIHMAI--RRNHRCPICRRR 145
Cdd:COG5574 218 CFLCLEE-----PEVPSCTPCGHLFCLSCLLISWtkKKYEFCPLCRAK 260

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.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 24584571  96 ENSTCSICLLPWTDNGIHRLVSLRCGHLFGSSCIHMAI-RRNHRCPICRRRARHFHVRRIY 155
Cdd:cd16450   1 EGNTCPICFEPWTSSGEHRLVSLKCGHLFGYSCIEKWLkGKGKKCPQCNKKAKRSDIRPLY 61

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.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 24584571  94 MVENSTCSICLLPWTDNGIHRLvsLRCGHLFGSSCIHMAIRR-NHRCPICRR 144
Cdd:cd16473   1 MLECEECAICLENYQNGDLLRG--LPCGHVFHQNCIDVWLERdNHCCPVCRW 50

RING finger, H2 subclass, found in Arabidopsis thaliana protein WAV3 homolog 2 (WAVH2) and similar proteins; WAVH2, also known as RING-type E3 ubiquitin transferase WAVH2, is a probable E3 ubiquitin-protein ligase involved in the regulation of root growth. It acts as a positive regulator of root gravitropism. WAVH2 contains a C3H2C3-type RING-H2 finger.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 24584571  98 STCSICLLPWTDNGIHRLVSLRCGHLFGSSCIHMAIR-RNHRCPICRRRARH 148
Cdd:cd23114   5 SECSICLETMKPGSGHAIFTAECSHSFHFECIAGNVRhGNLRCPVCRAKWKE 56

RING finger, HC subclass, found in RING finger protein 4 (RNF4) and similar proteins; RNF4, also known as small nuclear ring finger protein (SNURF), is a SUMO-targeted E3 ubiquitin-protein ligase with a pivotal function in the DNA damage response (DDR) by interacting with the deubiquitinating enzyme ubiquitin-specific protease 11 (USP11), a known DDR-component, and further facilitating DNA repair. It plays a novel role in preventing the loss of intact chromosomes and ensures the maintenance of chromosome integrity. Moreover, RNF4 is responsible for the UbcH5A-catalyzed formation of K48 chains that target SUMO-modified promyelocytic leukemia (PML) protein for proteasomal degradation in response to arsenic treatment. It also interacts with telomeric repeat binding factor 2 (TRF2) in a small ubiquitin-like modifier (SUMO)-dependent manner and preferentially targets SUMO-conjugated TRF2 for ubiquitination through SUMO-interacting motifs (SIMs). Furthermore, RNF4 can form a complex with a Ubc13-ubiquitin conjugate and Ube2V2. It catalyzes K63-linked polyubiquitination by the Ube2V2-Ubc13 (ubiquitin-loaded) complex. Meanwhile, RNF4 negatively regulates nuclear factor kappa B (NF-kappaB) signaling by down-regulating transforming growth factor beta (TGF-beta)-activated kinase 1 (TAK1)-TAK1-binding protein2 (TAB2). RNF4 contains four SIMs followed by a C3HC4-type RING-HC finger at the C-terminus.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 24584571  99 TCSICLLPWTD--NGIHRLVSLRCGHLFGSSCIHMAIRRNHRCPICRRRARH 148
Cdd:cd16533   5 SCPICMDGYSEivQSGRLIVSTECGHVFCSQCLRDSLKNANTCPTCRKKLNH 56

RING finger, H2 subclass, found in RING finger protein 181 (RNF181) and similar proteins; RNF181, also known as HSPC238, is a platelet E3 ubiquitin-protein ligase containing a C3H2C3-type RING-H2 finger. It interacts with the KVGFFKR motif of platelet integrin alpha(IIb)beta3, suggesting a role for RNF181-mediated ubiquitination in integrin and platelet signaling. It also suppresses the tumorigenesis of hepatocellular carcinoma (HCC) through the inhibition of extracellular signal-regulated kinase/mitogen-activated protein kinase (ERK/MAPK) signaling in the liver.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....
gi 24584571 100 CSICLLPWTDNGIHRlvSLRCGHLFGSSCIHMAIRRNHRCPICR 143
Cdd:cd16669   2 CPICLLEFEEGETVK--QLPCKHSFHSDCILPWLGKTNSCPLCR 43

Modified RING finger found in peroxin-12 (PEX12) and similar proteins; PEX12, also known as peroxisome assembly protein 12 or peroxisome assembly factor 3 (PAF-3), is a RING finger domain-containing integral membrane peroxin required for protein import into peroxisomes. Mutations in human PEX12 result in the peroxisome deficiency Zellweger syndrome of complementation group III (CG-III), a lethal neurological disorder. PEX12 also functions as an E3-ubiquitin ligase that facilitates the PEX4-dependent monoubiquitination of PEX5, a key player in peroxisomal matrix protein import, to control PEX5 receptor recycling or degradation. PEX12 contains a modified RING finger that lacks the third, fourth, and eighth zinc-binding residues of the consensus RING finger motif, suggesting PEX12 may only bind one zinc ion.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*...
gi 24584571  98 STCSICLLPWTDNGihrlVSLRCGHLFGSSCIHMAIRRNHRCPICRRRARHFHVRRIY 155
Cdd:cd16451   1 GICPLCRKKRTNPT----ALATSGYVFCYPCIYRYVKEHGRCPVTGYPASLDHLIKLY 54

RING finger, HC subclass, found in RING finger protein 138 (RNF138) and similar proteins; RNF138, also known as Nemo-like kinase-associated RING finger protein (NARF) or NLK-associated RING finger protein, is an E3 ubiquitin-protein ligase that plays an important role in glioma cell proliferation, apoptosis, and cell cycle. It specifically cooperates with the E2 conjugating enzyme E2-25K (Hip-2/UbcH1), regulates the ubiquitylation and degradation of T cell factor/lymphoid enhancer factor (TCF/LEF), and further suppresses Wnt-beta-catenin signaling. RNF138, together with three closely related proteins: RNF114, RNF125 and RNF166, forms a novel family of ubiquitin ligases with a C3HC4-type RING-HC finger, a C2HC-, and two C2H2-type zinc fingers, as well as a ubiquitin interacting motif (UIM).

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 24584571  99 TCSICLLPWTDNgihrlVSLR-CGHLFGSSCIHMAIRR-NHRCPICRRRAR 147
Cdd:cd16544   4 TCPVCQEVLKDP-----VELPpCRHIFCKACILLALRSsGARCPLCRGPVG 49

RING finger, HC subclass, found in Arabidopsis thaliana protein BENZOIC ACID HYPERSENSITIVE 1 (BAH1) and similar proteins; This subfamily includes Arabidopsis thaliana BAH1 and BAH1-like. BAH1, also known as protein NITROGEN LIMITATION ADAPTATION (NLA), or RING-type E3 ubiquitin transferase BAH1, acts as an E3 ubiquitin-protein ligase that mediates E2-dependent protein ubiquitination. It plays a role in salicylic acid-mediated negative feedback regulation of salicylic acid (SA) accumulation. It may be involved in the overall regulation of SA, benzoic acid and phenylpropanoid biosynthesis. It controls the adaptability to nitrogen limitation by channeling the phenylpropanoid metabolic flux to the induced anthocyanin synthesis. BAH1-like, also known as RING finger protein 178, or RING-type E3 ubiquitin transferase BAH1-like, is a probable E3 ubiquitin-protein ligase. Members of this subfamily contain a typical C3HC4-type RING-HC finger.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 24584571  99 TCSICLLPWTDNgihrlVSLRCGHLFGSSC--------IHMAI---RRNHRCPICR 143
Cdd:cd23127  10 TCSICLDTVFDP-----VALGCGHLFCNSCacsaasvlIFQGLkaaPPEAKCPLCR 60

RING finger, HC subclass, found in tripartite motif-containing protein TRIM25 and similar proteins; TRIM25, also known as estrogen-responsive finger protein (EFP), RING finger protein 147 (RNF147), or RING-type E3 ubiquitin transferase, is an E3 ubiquitin/ISG15 ligase that is induced by estrogen and is therefore particularly abundant in placenta and uterus. TRIM25 regulates various cellular processes through E3 ubiquitin ligase activity, transferring ubiquitin and ISG15 to target proteins. It mediates K63-linked polyubiquitination of retinoic acid inducible gene I (RIG-I) that is crucial for downstream antiviral interferon signaling. It is also required for melanoma differentiation-associated gene 5 (MDA5) and mitochondrial antiviral signaling (MAVS, also known as IPS-1, VISA, Cardiff) mediated activation of nuclear factor-kappaB (NF-kappaB) and interferon production. Upon UV irradiation, TRIM25 interacts with mono-ubiquitinated PCNA and promotes its ISG15 modification (ISGylation), suggesting a crucial role in termination of error-prone translesion DNA synthesis. TRIM25 also functions as a novel regulator of p53 and Mdm2. It enhances p53 and Mdm2 abundance by inhibiting their ubiquitination and degradation in 26S proteasomes. Meanwhile, it inhibits p53's transcriptional activity and dampens the response to DNA damage, and is essential for medaka development and this dependence is rescued by silencing of p53. Moreover, TRIM25 is involved in the host cellular innate immune response against retroviral infection. It interferes with the late stage of feline leukemia virus (FeLV) replication. Furthermore, TRIM25 acts as an oncogene in gastric cancer. Its blockade by RNA interference inhibits migration and invasion of gastric cancer cells through transforming growth factor-beta (TGF-beta) signaling, suggesting it presents a novel target for the detection and treatment of gastric cancer. In addition, TRIM25 acts as an RNA-specific activator for Lin28a/TuT4-mediated uridylation. TRIM25 belongs to the C-IV subclass of 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        50
                ....*....|....*....|....*....|....*....|....*....|
gi 24584571  99 TCSICLLPWTDNgihrlVSLRCGHLFGSSCIHMAIRRNH----RCPICRR 144
Cdd:cd16597   7 TCSICLELFKDP-----VTLPCGHNFCGVCIEKTWDSQHgseySCPQCRA 51

RING finger, H2 subclass, found in RING finger protein 12 (RNF12) and similar proteins; 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. Its functional activity is regulated by phosphorylation-dependent nucleocytoplasmic shuttling. It is negatively regulated by pluripotency factors in embryonic stem cells. p53 represses its transcription through Sp1. RNF12 is the primary factor responsible for X chromosome inactivation (XCI) in female placental mammals. It is an indispensable factor in up-regulation of Xist transcription, thereby leading to initiation of random XCI. It also targets REX1, an inhibitor of XCI, for proteasomal degradation. RNF12 also acts as a co-regulator for a range of transcription factors, particularly those containing a LIM homeodomain, and modulates the formation of transcriptional multiprotein complexes. It is a negative regulator of Smad7, which in turn negatively regulates the signaling of type I receptors from the transforming growth factor beta (TGF-beta) superfamily. In addition, paternal RNF12 is a critical survival factor for milk-producing alveolar cells. RNF12 contains an nuclear localization signal (NLS) and a C3H2C3-type RING-H2 finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*.
gi 24584571  99 TCSICLLPWTDNgiHRLVSLRCGHLFGSSCIHMAIRRNHRCPICRR 144
Cdd:cd16674   2 TCSVCITEYTEG--NKLRKLPCSHEYHVHCIDRWLSENSTCPICRR 45

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 24584571    100 CSICLlpwtDNGIHRLVSLRCGHLFGSSCIHMAIRRNH-RCPIC 142
Cdd:smart00184   1 CPICL----EEYLKDPVILPCGHTFCRSCIRKWLESGNnTCPIC 40

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        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 24584571  96 ENSTCSICLlpwtdNGIHRLVSLRCGHLFGSSCIH--MAIRRNHRCPICRRRARHF 149
Cdd:cd23132   1 EEFLCCICL-----DLLYKPVVLECGHVFCFWCVHrcMNGYDESHCPLCRRPYDHF 51

RING finger, HC subclass, found in tripartite motif-containing protein 62 (TRIM62) and similar proteins; TRIM62, also known as Ductal Epithelium Associated Ring Chromosome 1 (DEAR1), is a cytoplasmic E3 ubiquitin-protein ligase that was identified as a dominant regulator of acinar morphogenesis in the mammary gland. It is implicated in the inflammatory response of immune cells by regulating the Toll-like receptor 4 (TLR4) signaling pathway, leading to increased activity of the activator protein 1 (AP-1) transcription factor in primary macrophages. It is also involved in muscular protein homeostasis, especially during inflammation-induced atrophy, and may play a role in the pathogenesis of ICU-acquired weakness (ICUAW) by activating and maintaining inflammation in myocytes. Moreover, TRIM62 facilitates K27-linked poly-ubiquitination of CARD9 and also regulates CARD9-mediated anti-fungal immunity and intestinal inflammation. It also functions as a chromosome 1p35 tumor suppressor and negatively regulates transforming growth factor beta (TGFbeta)-driven epithelial-mesenchymal transition (EMT) by binding to and promoting the ubiquitination of SMAD3, a major effector of TGFbeta-mediated EMT. TRIM62 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 24584571  99 TCSICLLPWTDNgihrlVSLRCGHLFGSSCI--HMAIRRNHRCPICRR 144
Cdd:cd16608   8 LCSICLSIYQDP-----VSLGCEHYFCRQCIteHWSRSEHRDCPECRR 50

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.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....
gi 24584571 100 CSICLLPWTDNGIHRlvSLRCGHLFGSSCIHMAIRRNHRCPICR 143
Cdd:cd16474   3 CTICLSDFEEGEDVR--RLPCMHLFHQECVDQWLSTNKRCPICR 44

RING finger, HC subclass, found in Mus musculus tripartite motif-containing protein 43 (TRIM43) and similar propteins; This subfamily includes TRIM43A, TRIM43B and TRIM43C, which are expressed specifically in mouse preimplantation embryos. They contain a typical C3HC4-type RING-HC finger.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 24584571  96 ENSTCSICLLPWTDNgihrlVSLRCGHLFGSSCIHMA---IRRNHRCPICRR 144
Cdd:cd23133   2 ETLTCSICQGIFMNP-----VYLRCGHKFCEACLLLFqedIKFPAYCPMCRQ 48

Modified RING finger, HC subclass (C3HC3D-type), found in ligand of Numb protein LNX1, LNX2, and similar proteins; The ligand of Numb protein X (LNX) family, also known as PDZ and RING (PDZRN) family, includes LNX1-5, which can interact with Numb, a key regulator of neurogenesis and neuronal differentiation. LNX5 (also known as PDZK4 or PDZRN4L) shows high sequence homology to LNX3 and LNX4, but it lacks the RING domain. LNX1-4 proteins function as E3 ubiquitin ligases and have a unique domain architecture consisting of an N-terminal RING-HC finger for E3 ubiquitin ligase activity and either two or four PDZ domains necessary for substrate-binding. LNX1/LNX2-like proteins contain a modified C3HC3D-type RING-HC finger and four PDZ domains. This model corresponds to the RING finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*
gi 24584571  99 TCSICLLPWTDNgihrlVSLRCGHLFGSSCIHMAIRRNHRCPICR 143
Cdd:cd16637   3 TCHICLQPLVEP-----LDTPCGHTFCYKCLTNYLKIQQCCPLDR 42

RING finger, HC subclass, found in tripartite motif-containing protein TRIM65 and similar proteins; TRIM65 is an E3 ubiquitin-protein ligase that interacts with the innate immune receptor MDA5, enhancing its ability to stimulate interferon-beta signaling. It functions as a potential oncogenic protein that negatively regulates p53 through ubiquitination, providing insight into the development of novel approaches targeting TRIM65 for non-small cell lung carcinoma (NSCLC) treatment, and also overcoming chemotherapy resistance. Moreover, TRIM65 negatively regulates microRNA-driven suppression of mRNA translation by targeting TNRC6 proteins for ubiquitination and degradation. TRIM65 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        50
                ....*....|....*....|....*....|....*....|....*....|....*..
gi 24584571  96 ENSTCSICLLPWTDNgihrlVSLRCGHLFGSSCIH-MAIRRNHR---CPICRRRARH 148
Cdd:cd16609   2 EELTCSICLGLYQDP-----VTLPCQHSFCRACIEdHWRQKDEGsfsCPECRAPFPE 53

Zinc finger, C3HC4 type (RING finger);

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|...
gi 24584571   100 CSICLLPWTDNgihrLVSLRCGHLFGSSCIHMAIRRNHRCPIC 142
Cdd:pfam13923   2 CPICMDMLKDP----STTTPCGHVFCQDCILRALEASNECPLC 40

RING finger, HC subclass, found in Caenorhabditis elegans BRCA1-associated RING domain protein 1 (CeBARD1) and similar proteins; CeBARD1, also called Ce-BRD-1, Cebrd-1, or RING-type E3 ubiquitin transferase BARD1, is a constituent of the CeBCD complex that possesses E3 ubiquitin-protein ligase activity. It plays a role in triggering cellular responses at damage sites in response to DNA damage that may be induced by ionizing radiation. It protects against chromosome non-disjunction and nuclear fragmentation during meiotic double-strand break repair to ensure sister chromatid recombination and aid chromosome stability. CeBARD1 contains a typical C3HC4-type RING-HC finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*.
gi 24584571 100 CSICllpwTDNGIHRLVSLRCGHLFGSSCIHMAIRRNHRCPICRRR 145
Cdd:cd23143   4 CVIC----SEPQIDTFLLSSCGHIYCWECFTEFIEKRHMCPSCRFP 45

RING finger, HC subclass, found in RING finger protein 180 (RNF180) and similar proteins; RNF180, also known as Rines, is a membrane-bound E3 ubiquitin-protein ligase well conserved among vertebrates. It is a critical regulator of the monoaminergic system, as well as emotional and social behavior. It interacts with brain monoamine oxidase A (MAO-A) and targets it for ubiquitination and degradation. It also functions as a novel tumor suppressor in gastric carcinogenesis. The hypermethylated CpG site count of the RNF180 DNA promoter can be used to predict survival of gastric cancer. RNF180 contains a novel conserved dual specificity protein phosphatase Rines conserved (DSPRC) domain, a basic coiled-coil domain, a C3HC4-type RING-HC finger, and a C-terminal hydrophobic region that is predicted to be a transmembrane domain.

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                ....*....|....*....|....*....|....*....|....*....|....*.
gi 24584571  96 ENSTCSICLlpwtDNGIHRLVSLRCGHLFGSSCIHMAIRRNH---RCPICRRRARH 148
Cdd:cd16554   1 ESLTCPVCL----DLYYDPYMCYPCGHIFCEPCLRQLAKSSPkntPCPLCRTTIRR 52

RING finger, H2 subclass, found in RING finger proteins RNF38, RNF44, and similar proteins; This subfamily includes RING finger proteins RNF38, RNF44, and similar proteins. RNF38 is a nuclear E3 ubiquitin protein ligase that plays a role in regulating p53. RNF44 is an uncharacterized RING finger protein that shows high sequence similarity to RNF38. Both RNF38 and RNF44 contain a coiled-coil motif, a KIL motif (Lys-X2-Ile/Leu-X2-Ile/Leu, X can be any amino acid), and a C3H2C3-type RING-H2 finger. In addition, RNF38 harbors two potential nuclear localization signals.

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                ....*....|....*....|....*....|....*....|....*...
gi 24584571  96 ENSTCSICLLPWTDNgiHRLVSLRCGHLFGSSCIHMAIRRNHRCPICR 143
Cdd:cd16472   1 DQTQCVVCMCDYEKR--QLLRVLPCSHEFHAKCIDKWLKTNRTCPICR 46

RING finger, HC subclass, found in RING finger protein 8 (RNF8) and similar proteins; RNF8 is a telomere-associated E3 ubiquitin-protein ligase that plays an important role in DNA double-strand break (DSB) repair via histone ubiquitination. It is localized in the nucleus and interacts with class III E2s (UBE2E2, UbcH6, and UBE2E3), but not with other E2s (UbcH5, UbcH7, UbcH10, hCdc34, and hBendless). It recruits UBC13 for lysine 63-based self polyubiquitylation. Its deficiency causes neuronal pathology and cognitive decline, and its loss results in neuron degeneration. RNF8, together with RNF168, catalyzes a series of ubiquitylation events on substrates such as H2A and H2AX, with the H2AK13/15 ubiquitylation being particularly important for recruitment of repair factors p53-binding protein 1 (53BP1) or the RAP80-BRCA1 complex to sites of DSBs. RNF8 mediates the ubiquitination of gammaH2AX, and recruits 53BP1 and BRCA1 to DNA damage sites which promotes DNA damage response (DDR) and inhibits chromosomal instability. Moreover, RNF8 interacts with retinoid X receptor alpha (RXR alpha) and enhances its transcription-stimulating activity. It also regulates the rate of exit from mitosis and cytokinesis. RNF8 contains an N-terminal forkhead-associated (FHA) domain and a C-terminal C3HC4-type RING-HC finger.

                        10        20        30
                ....*....|....*....|....*....|
gi 24584571 116 VSLRCGHLFGSSCIHMAIRRNHRCPICRRR 145
Cdd:cd16535  15 VTLNCSHSFCSYCITEWMKRKKECPICRKP 44

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.

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                ....*....|....*....|....*....|....*....|....*....|....*....|
gi 24584571  87 LNQRLDRMVENSTCSICLLPWTDNgihrlVSLRCGHLFGSSCIHMAI---RRNHRCPICR 143
Cdd:cd16498   6 VQEVISAMQKNLECPICLELLKEP-----VSTKCDHQFCRFCILKLLqkkKKPAPCPLCK 60

RING finger, HC subclass, found in RING finger protein 185 (RNF185) and similar proteins; RNF185 is an E3 ubiquitin-protein ligase of endoplasmic reticulum-associated degradation (ERAD) that targets cystic fibrosis transmembrane conductance regulator (CFTR). It controls the degradation of CFTR and CFTR F508del allele in a RING- and proteasome-dependent manner, but does not control that of other classical ERAD model substrates. It also negatively regulates osteogenic differentiation by targeting dishevelled2 (Dvl2), a key mediator of the Wnt signaling pathway, for degradation. Moreover, RNF185 regulates selective mitochondrial autophagy through interaction with the Bcl-2 family protein BNIP1. It also plays an important role in cell adhesion and migration through the modulation of cell migration by ubiquitinating paxillin. RNF185 contains a C3HC4-type RING-HC finger.

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                ....*....|....*....|....*....|....*....|....*..
gi 24584571 100 CSICLlpwtDNGIHRLVSLrCGHLFGSSCIH--MAIRRNHR-CPICR 143
Cdd:cd16744   3 CNICL----DTAKDAVVSL-CGHLFCWPCLHqwLETRPNRQvCPVCK 44

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 24584571  99 TCSICLlpwtdNGIHRLVSLRCGHLFGSSCIHMAIR-RNHRCPIC 142
Cdd:cd16449   2 ECPICL-----ERLKDPVLLPCGHVFCRECIRRLLEsGSIKCPIC 41

RING finger, HC subclass, found in tripartite motif-containing protein 77 (TRIM77) and similar proteins; TRIM77 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 two consecutive zinc-binding domains, a C3HC4-type RING-HC finger and Bbox2, as well as a SPRY/B30.2 domain positioned C-terminal to the RBCC domain.

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                ....*....|....*....|....*....|....*....|....*....|.
gi 24584571  96 ENSTCSICLLPWTDNgihrlVSLRCGHLFGSSCIHMAIRR---NHRCPICR 143
Cdd:cd16543   2 DQLTCSICLDLLKDP-----VTIPCGHSFCMNCITLLWDRkqgVPSCPQCR 47

Modified RING finger, HC subclass (C3HC3D-type), found in tumor necrosis factor (TNF) receptor-associated factor 6 (TRAF6) and similar proteins; TRAF6, also known as interleukin-1 signal transducer or RING finger protein 85 (RNF85), is a cytoplasmic adapter protein that mediates signals induced by the tumor necrosis factor receptor (TNFR) superfamily and Toll-like receptor (TLR)/interleukin-1 receptor (IL-1R) family. It functions as a mediator involved in the activation of mitogen-activated protein kinase (MAPK), phosphoinositide 3-kinase (PI3K), and interferon regulatory factor pathways, as well as in IL-1R-mediated activation of NF-kappaB. TRAF6 is also an oncogene that plays a vital role in K-RAS-mediated oncogenesis. TRAF6 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 24584571 100 CSICLLpwtdnGIHRLVSLRCGHLFGSSCIHMAIRR-NHRCPI 141
Cdd:cd16643   4 CPICLM-----ALREPVQTPCGHRFCKACILKSIREaGHKCPV 41

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 24584571 100 CSICLLPWtdngiHRLVSLRCGHLFGSSCIHMAIRRNHR--CPICRRRA 146
Cdd:cd16599   7 CPICYEPF-----REAVTLRCGHNFCKGCVSRSWERQPRapCPVCKEAS 50

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 24584571  99 TCSICLLPWTDNGIhrLVSLRCGHLFGSSCIHMAIRRNHRCPICRR 144
Cdd:cd16465   1 CCPICCSEYVKDEI--ATELPCHHLFHKPCITAWLQKSGTCPVCRH 44

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 24584571  96 ENSTCSICLLPWTDNgihrlVSLRCGHLFGSSCIHMAIRRNHRCPICRR 144
Cdd:cd16539   4 LPFACFICRKPFKNP-----VVTKCGHYFCEKCALKHYRKSKKCFVCGK 47

RING-finger-containing ubiquitin ligase [Posttranslational modification, protein turnover, chaperones];

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                ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 24584571  84 VKTLNQRLDRMVENSTCSICLLPWTDNgiHRLVSLRCGHLFGSSCIHMAI-RRNHRCPICR 143
Cdd:COG5540 310 KPLSIERAVEADKGVECAICMSNFIKN--DRLRVLPCDHRFHVGCVDKWLlGYSNKCPVCR 368

RING finger, H2 subclass, found in RING finger protein 165 (RNF165) and similar proteins; 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. RNF165 contains two serine rich domains, a nuclear localization signal, an NRG-TIER domain, and a C-terminal C3H2C3-type RING-H2 finger that is responsible for the enhancement of BMP-Smad1/5/8 signaling in the spinal cord.

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                ....*....|....*....|....*....|....*....|....*..
gi 24584571  97 NSTCSICLLPWTDNGIHRlvSLRCGHLFGSSCIHMAIRRNHRCPICR 143
Cdd:cd16682   7 DEKCTICLSMLEDGEDVR--RLPCMHLFHQLCVDQWLAMSKKCPICR 51

RING finger, HC subclass, found in RING finger protein 10 (RNF10) and similar proteins; RNF10 is an E3 ubiquitin-protein ligase that interacts with mesenchyme Homeobox 2 (MEOX2) transcription factor, a regulator of the proliferation, differentiation and migration of vascular smooth muscle cells and cardiomyocytes; it enhances Meox2 activation of the p21 promoter. It also regulates the expression of myelin-associated glycoprotein (MAG) genes and is required for myelin production in Schwann cells of the peripheral nervous system. Moreover, RNF10 regulates retinoic acid-induced neuronal differentiation and the cell cycle exit of P19 embryonic carcinoma cells. RNF10 contains a C3HC4-type RING-HC finger and three putative nuclear localization signals.

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                ....*....|....*....|....*....|....*....|....*...
gi 24584571  99 TCSICLLPWTDNGIhrlvsLRCGHLFGSSCI----HMAIRRNHRCPIC 142
Cdd:cd16536   2 QCPICLEPPVAPRI-----TRCGHIFCWPCIlrylSLSEKKWRKCPIC 44

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 24584571 119 RCGHLFGSSCIHMAIRRNHRCPIC 142
Cdd:cd16504  19 KCGHSFCYKCIVKHLEQKNRCPKC 42

RING finger, HC subclass, found in peroxin-10 (PEX10) and similar proteins; PEX10, also known as peroxisome biogenesis factor 10, peroxisomal biogenesis factor 10, peroxisome assembly protein 10, or RING finger protein 69 (RNF69), is an integral peroxisomal membrane protein with two transmembrane regions and a C3HC4-type RING-HC finger within its cytoplasmically exposed C-terminus. It plays an essential role in peroxisome assembly, import of target substrates, and recycling or degradation of protein complexes and amino acids. It is an essential component of the spinal locomotor circuit, and thus its mutations may be involved in peroxisomal biogenesis disorders (PBD). Mutations in human PEX10 also result in autosomal recessive ataxia. Moreover, PEX10 functions as an E3-ubiquitin ligase with an E2, UBCH5C. It mono- or poly-ubiquitinates PEX5, a key player in peroxisomal matrix protein import, in a UBC4-dependent manner, to control PEX5 receptor recycling or degradation. It also links the E2 ubiquitin conjugating enzyme PEX4 to the protein import machinery of the peroxisome.

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gi 24584571 100 CSICLLPWTDNgihrlVSLRCGHLFGSSCIHMAIRRNHRCPICRrraRHFHVRRI 154
Cdd:cd16527   3 CSLCLEERRHP-----TATPCGHLFCWSCITEWCNEKPECPLCR---EPFQPQRL 49

RING finger, H2 subclass, found in Arabidopsis thaliana MED25-binding RING-H2 protein (MBR) and similar proteins; This subfamily includes MBR1 and MBR2 (also called HAL3-interacting protein 1 or AtHIP1). They are E3 ubiquitin-protein ligases that function as regulators of MED25 stability by targeting MED25 for degradation in a RING-H2-dependent manner. Proteasome-dependent degradation of MED25 seems to activate its function as a positive regulator of FLOWERING LOCUS T (FT) and is important to induce the expression of FT, and consequently to promote flowering. MBR2 may also function downstream of HAL3 and be required for HAL3-regulated plant growth. Activation of MBR2 by HAL3 may lead to the degradation of cell cycle suppressors, resulting in enhancement of cell division and plant growth. Both MBR1 and MBR2 contain a C3H2C3-type RING-H2 finger.

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gi 24584571 100 CSICLLPWTDNgiHRLVSLRCGHLFGSSCIHMAIRRNHRCPICRRRA 146
Cdd:cd23113   5 CCICQEEYEEG--DELGTIECGHEYHSDCIKQWLVQKNLCPICKATA 49