Ring finger domain;

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|..
gi 21313294   335 CTICQAEF---QKPVLLFCQHIFCEECITLWFNREKTCPLCR 373
Cdd:pfam13639   3 CPICLEEFeegDKVVVLPCGHHFHRECLDKWLRSSNTCPLCR 44

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 21313294    335 CTICQAEFQK-PVLLFCQHIFCEECITLWF-NREKTCPLC 372
Cdd:smart00184   1 CPICLEEYLKdPVILPCGHTFCRSCIRKWLeSGNNTCPIC 40

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

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 21313294 321 VPASKRQCSDMDGICTICQAEF-------------QKPVLLFCQHIFCEECITLWFNREKTCPLCR 373
Cdd:COG5243 276 PTATEEQLTNSDRTCTICMDEMfhpdheplprgldMTPKRLPCGHILHLHCLKNWLERQQTCPICR 341

RING finger, HC subclass, found in RING finger and transmembrane domain-containing protein 2(RNFT2); RNFT2, also known as transmembrane protein 118 (TMEM118), is a multi-pass membrane protein containing a C3HC4-type RING-HC finger. Its biological role remains unclear.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 21313294 320 GVPASKRQCSDMDGICTICQAEFQKPVLLFCQHIFCEECITLWFNREKTCPLCRTVISECINKWKDG 386
Cdd:cd16742   1 GVRATSQQCSEAGDICAICQAEFREPLILICQHVFCEECLCLWFDRERTCPLCRSVVVETLRCWKDG 67

RING finger, HC subclass, found in RING finger protein 213 (RNF213) and similar proteins; RNF213, also known as ALK lymphoma oligomerization partner on chromosome 17 or Moyamoya steno-occlusive disease-associated AAA+ and RING finger protein (mysterin), is an intracellular soluble protein that functions as an E3 ubiquitin-protein ligase and AAA+ ATPase, which possibly contributes to vascular development through mechanical processes in the cell. It plays a unique role in endothelial cells for proper gene expression in response to inflammatory signals from the environment. Mutations in RNF213 may be associated with Moyamoya disease (MMD), an idiopathic cerebrovascular occlusive disorder prevalent in East Asia. It also acts as a nuclear marker for acanthomorph phylogeny. RNF213 contains two tandem enzymatically active AAA+ ATPase modules and a C3HC4-type RING-HC finger. It can form a huge ring-shaped oligomeric complex.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....
gi 21313294 335 CTICQAEFQKPVLLFCQHIFCEECITLWFNREKTCPLCRTVISE 378
Cdd:cd16561   5 CSICLEDLNDPVKLPCDHVFCEECIRQWLPGQMSCPLCRTELPD 48

RING finger, HC subclass, found in tripartite motif-containing protein 69 (TRIM69) and similar proteins; TRIM69, also known as RFP-like domain-containing protein trimless or RING finger protein 36 (RNF36), is a testis E3 ubiquitin-protein ligase that plays a specific role in apoptosis and may also play an important role in germ cell homeostasis during spermatogenesis. TRIM69 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 21313294 331 MDGICTICQAEFQKPVLLFCQHIFCEECITLWFNR---EKTCPLCRTV 375
Cdd:cd16611   3 EELHCPLCLDFFRDPVMLSCGHNFCQSCITGFWELqaeDTTCPECREL 50

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        40
                ....*....|....*....|....*....|....*....|..
gi 21313294 335 CTICQAEFQKPVLLFCQHIFCEECITLWFNREKTCPLCRTVI 376
Cdd:cd16535   4 CSICSELFIEAVTLNCSHSFCSYCITEWMKRKKECPICRKPI 45

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
                ....*....|....*....|....*....|....*....|....*....
gi 21313294 332 DGICTICQAEFQKPV-LLFCQHIFCEECITLWFNREKT-CPLCRTVISE 378
Cdd:cd16544   2 ELTCPVCQEVLKDPVeLPPCRHIFCKACILLALRSSGArCPLCRGPVGK 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.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*
gi 21313294 335 CTICQAEFQKP---VLLFCQHIFCEECITLWFNREKTCPLCRTVI 376
Cdd:cd16465   2 CPICCSEYVKDeiaTELPCHHLFHKPCITAWLQKSGTCPVCRHVL 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.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....
gi 21313294 333 GICTICQAEFQKP-VLLFCQHIFCEECITLWFNREKTCPLCRTV 375
Cdd:cd16506   1 DTCPICLDEIQNKkTLEKCKHSFCEDCIDRALQVKPVCPVCGVV 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.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|
gi 21313294 334 ICTICQAEFQKPVLLFCQHIFCEECITLWFN-REKTCPLC 372
Cdd:cd16449   2 ECPICLERLKDPVLLPCGHVFCRECIRRLLEsGSIKCPIC 41

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.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 21313294 335 CTICQAEFQKPVLLFCQHIFCEECITLWFNREKTCPLCRTVIS 377
Cdd:cd16527   3 CSLCLEERRHPTATPCGHLFCWSCITEWCNEKPECPLCREPFQ 45

Zinc finger, C3HC4 type (RING finger);

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*....
gi 21313294   332 DGICTICQAEFQKPVLLFCQH-IFCEECITLWFNREKTCPLCRTVISEC 379
Cdd:pfam13920   2 DLLCVICLDRPRNVVLLPCGHlCLCEECAERLLRKKKKCPICRQPIESV 50

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
                ....*....|....*....|....*....|....*....|...
gi 21313294 335 CTICQAEFQKPVLLFCQHIFCEECITLWFNR----EKTCPLCR 373
Cdd:cd16609   6 CSICLGLYQDPVTLPCQHSFCRACIEDHWRQkdegSFSCPECR 48

RING finger, HC subclass, found in E3 ubiquitin-protein ligase Deltex3 (DTX3) and similar proteins; DTX3, also known as RING finger protein 154 (RNF154), is an E3 ubiquitin-protein ligase that belongs to the Deltex (DTX) family. In contrast to other DTXs, DTX3 does not contain two N-terminal Notch-binding WWE domains, but a short unique N-terminal domain, suggesting it does not interact with the intracellular domain of Notch. Its C-terminal region includes a C3HC4-type RING-HC finger, and a previously unidentified C-terminal domain.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 21313294 332 DGICTICQAEFQ-KPVLLFCQHIFCEECITLWFNREKTCPLCRTVISECI 380
Cdd:cd16711   1 EETCPICLGEIQnKKTLDKCKHSFCEDCITRALQVKKACPMCGEFYGQLI 50

N1R/p28-like protein; Provisional

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*...
gi 21313294  335 CTICQAE-FQKP-------VLLFCQHIFCEECITLWFNREKTCPLCRT 374
Cdd:PHA02929 177 CAICMEKvYDKEiknmyfgILSNCNHVFCIECIDIWKKEKNTCPVCRT 224

RING finger, HC subclass, found in RING finger protein 39 (RNF39) and similar proteins; RNF39, also called protein HZFw, may play a role in prolonged long term-potentiation (LTP) maintenance. It is involved in the etiology of Behcet's disease (BD). It may also be involved in HIV-1 replication. RNF39 acts as an E3 ubiquitin ligase that inhibits retinoic acid-inducible gene-I (RIG-I)-like receptor (RLR) pathways by mediating K48-linked ubiquitination and proteasomal degradation of DDX3X (DEAD-box RNA helicase 3, X-linked). RNF39 contains a typical C3HC4-type RING-HC finger.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 21313294 334 ICTICQAEFQKPVLLFCQHIFCEECITLWFNREKT---------CPLCRTVI 376
Cdd:cd16592   6 TCPICLGYFKDPVILDCEHSFCRACIARHWGQEAMegngaegvfCPQCGEPC 57

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 21313294 334 ICTICQAEFQKPVLLF-CQHIFCEECITLWFNREK-TCPLCR-TVISECIN 381
Cdd:cd16503   4 TCSICQDLLHDCVSLQpCMHNFCAACYSDWMERSNtECPTCRaTVQRVNKN 54

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        50
                ....*....|....*....|....*....|....*....|....*....|
gi 21313294 328 CSDMDGICTICQAEFQKPVLLFCQHIFCEECITLWFNREKT--CPLCRTV 375
Cdd:cd16608   2 SLKDELLCSICLSIYQDPVSLGCEHYFCRQCITEHWSRSEHrdCPECRRT 51

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.

                        10        20        30
                ....*....|....*....|....*....|....*....
gi 21313294 335 CTICQAEFQKPVLLFCQHIFCEECITLWFNREKTCPLCR 373
Cdd:cd16539   8 CFICRKPFKNPVVTKCGHYFCEKCALKHYRKSKKCFVCG 46

RING finger, H2 subclass, found in rice E3 ubiquitin-protein ligase EL5 and similar proteins; EL5, also known as protein ELICITOR 5, is an E3 ubiquitin-protein ligase containing an N-terminal transmembrane domain and a C3H2C3-type RING-H2 finger that is a binding site for ubiquitin-conjugating enzyme (E2). It can be rapidly induced by N-acetylchitooligosaccharide elicitor. EL5 catalyzes polyubiquitination via the Lys48 residue of ubiquitin, and thus plays a crucial role as a membrane-anchored E3 in the maintenance of cell viability after the initiation of root primordial formation in rice. It also acts as an anti-cell death enzyme that might be responsible for mediating the degradation of cytotoxic proteins produced in root cells after the actions of phytohormones. Moreover, EL5 interacts with UBC5b, a rice ubiquitin carrier protein, through its RING-H2 finger. EL5 is an unstable protein, and its degradation is regulated by the C3H2C3-type RING-H2 finger in a proteasome-independent manner.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....
gi 21313294 334 ICTICQAEFQKP----VLLFCQHIFCEECITLWFNREKTCPLCR 373
Cdd:cd16461   1 ECAICLSDYENGeelrRLPECKHAFHKECIDEWLKSNSTCPLCR 44

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.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|.
gi 21313294 334 ICTICQAEFQKPVLL-FCQHIFCEECITLWFNREKTCPLCR 373
Cdd:cd16634   3 ICPICSGVLEEPLQApHCEHAFCNACITEWLSRQQTCPVDR 43

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
                ....*....|....*....|....*....|....*....|....*..
gi 21313294 335 CTICQAEFQKPVLLFCQHIFCEECITLW---FNREKTCPLCRTVISE 378
Cdd:cd23133   6 CSICQGIFMNPVYLRCGHKFCEACLLLFqedIKFPAYCPMCRQPFNQ 52

RING finger, HC subclass, found in Saccharomyces cerevisiae radiation sensitivity protein 18 (RAD18) and similar proteins; RAD18, also called RING-type E3 ubiquitin transferase RAD18, acts as a postreplication repair E3 ubiquitin-protein ligase that associates with the E2 ubiquitin conjugating enzyme UBC2/RAD6 to form the UBC2-RAD18 ubiquitin ligase complex involved in postreplicative repair (PRR) of damaged DNA. The UBC2-RAD18 complex cooperates with RAD5 and the UBC13-MMS2 dimer to attach mono-ubiquitin chains on 'Lys-164' of POL30, which is necessary for PRR. The UBC2-RAD18 complex is also involved in prevention of spontaneous mutations caused by 7,8-dihydro-8-oxoguanine. RAD18 is an E3 RING-finger protein belonging to the UBC2/RAD6 epistasis group. It contains a typical C3HC4-type RING-HC finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....
gi 21313294 335 CTICQAEFQKPVLLFCQHIFCEECITLWFNREKTCPLCRTVISE 378
Cdd:cd23148   6 CHICKDLLKAPMRTPCNHTFCSFCIRTHLNNDARCPLCKAEVTE 49

RING finger, H2 subclass, found in TRAF-interacting protein (TRAIP) and similar proteins; TRAIP, also known as RING finger protein 206 (RNF206) or TRIP, is a ubiquitously expressed nucleolar E3 ubiquitin ligase important for cellular proliferation and differentiation. It is found near mitotic chromosomes and functions as a regulator of the spindle assembly checkpoint. TRAIP interacts with tumor necrosis factor (TNF)-receptor-associated factor (TRAF) proteins and inhibits TNF-alpha-mediated nuclear factor (NF)-kappaB activation. It also interacts with two tumor suppressors CYLD and spleen tyrosine kinase (Syk), and DNA polymerase eta, which facilitates translesional synthesis after DNA damage. TRAIP contains an N-terminal C3H2C2-type RING-H2 finger and an extended coiled-coil domain.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 21313294 334 ICTICQAEFQKPVLLF---CQHIFCEECITLWFNREKTCPLCR 373
Cdd:cd16480   1 YCTICSDFFDNSRDVAaihCGHTFHYDCLLQWFDTSRTCPQCR 43

RING finger, HC subclass, found in topoisomerase I-binding arginine/serine-rich protein (Topors) and similar proteins; Topors, also known as topoisomerase I-binding RING finger protein, tumor suppressor p53- binding protein 3, or p53-binding protein 3 (p53BP3), is a ubiquitously expressed nuclear E3 ubiquitin-protein ligase that can ligate both ubiquitin and small ubiquitin-like modifier (SUMO) to substrate proteins in the nucleus. It contains an N-terminal C3HC4-type RING-HC finger which ligates ubiquitin to its target proteins including DNA topoisomerase I, p53, NKX3.1, H2AX, and the AAV-2 Rep78/68 proteins. As a RING-dependent E3 ubiquitin ligase, Topors works with the E2 enzymes UbcH5a, UbcH5c, and UbcH6, but not with UbcH7, CDC34, or UbcH2b. Topors acts as a tumor suppressor in various malignancies. It regulates p53 modification, suggesting it may be responsible for astrocyte elevated gene-1 (AEG-1, also known as metadherin, or LYRIC) ubiquitin modification. Plk1-mediated phosphorylation of Topors inhibits Topors-mediated sumoylation of p53, whereas p53 ubiquitination is enhanced, leading to p53 degradation. It also functions as a negative regulator of the prostate tumor suppressor NKX3.1. Moreover, Topors is associated with promyelocytic leukemia nuclear bodies, and may be involved in the cellular response to camptothecin. It also plays a key role in the turnover of H2AX protein, discriminating the type of DNA damaging stress. Furthermore, Topors is a cilia-centrosomal protein associated with autosomal dominant retinal degeneration. Mutations in TOPORS cause autosomal dominant retinitis pigmentosa (adRP).

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*
gi 21313294 332 DGICTICQAEF--QKPVLLFCQHIFCEECITLWFNREKTCPLCRT 374
Cdd:cd16574   1 DSSCPICLDRFenEKAFLDGCFHAFCFTCILEWSKVKNECPLCKQ 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.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 21313294 334 ICTICQAEFQKPVLLF-CQHIFCEECITLWFNREKT---CPLCRTVISECI 380
Cdd:cd16554   4 TCPVCLDLYYDPYMCYpCGHIFCEPCLRQLAKSSPKntpCPLCRTTIRRVF 54

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

                          10        20        30
                  ....*....|....*....|....*....|....*....
gi 21313294   335 CTICQAEFQKPVLlFCQHIFCEECITL---WFNREKTCP 370
Cdd:pfam13445   1 CPICLELFTDPVL-PCGHTFCRECLEEmsqKKGGKFKCP 38

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 21313294 335 CTICQAEFQKPVLLFCQHIFCEECITLWFNREKTCPLCRTVI 376
Cdd:cd16514   4 CSLCLRLLYEPVTTPCGHTFCRACLERCLDHSPKCPLCRTSL 45

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

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 21313294 334 ICTICQAEF---QKPVLLFCQHIFCEECITLWFNREKTCPLCR 373
Cdd:cd16467   1 ECTICLGEYetgEKLRRLPCSHEFHSECVDRWLKENSSCPICR 43

RING finger, HC subclass, found in Arabidopsis thaliana BRCA1-associated RING domain protein 1 (AtBARD1) and similar proteins; AtBARD1, also called protein REPRESSOR OF WUSCHEL 1, binds specifically to H3K4me3 regions of target gene (e.g. WUS and WOX5) promoters to repress their transcription via chromatin remodeling. It is required for the shoot apical meristem (SAM) organization and maintenance, by confining WUS expression to the organizing center, and for the quiescent center (QC) development in the root apical meristem (RAM), by repressing WOX5 expression in the root proximal meristem. AtBARD1 plays a role in DNA repair and in cell-cycle control. It is required for the repair of DNA double-strand breaks (DSBs), both natural and induced by genotoxic stress, by homologous recombination (HR). AtBARD1 contains a typical C3HC4-type RING-HC finger.

                        10        20        30
                ....*....|....*....|....*....|....*....
gi 21313294 335 CTICQAEFQKPVLLFCQHIFCEECITLWFNREKTCPLCR 373
Cdd:cd23146   7 CPICLKLLNRPVLLPCDHIFCSSCITDSTKVGSDCPVCK 45

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

                        10        20        30        40
                ....*....|....*....|....*....|....*....|..
gi 21313294 335 CTICQAEF---QKPVLLFCQHIFCEECITLWFNREKTCPLCR 373
Cdd:cd16667   2 CAVCKEDFevgEEVRQLPCKHLFHPDCIVPWLELHNSCPVCR 43

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 21313294 334 ICTICQAEFQKPVLLFCQHIFCEECITLWFNR-EKTCPLCRTVI 376
Cdd:cd23138   4 NCSFCMQLPERPVTTPCGHNFCLKCFQKWMGQgKKTCGTCRSPI 47

RING finger, H2 subclass, found in Tetratricopeptide repeat protein 3 (TTC3) and similar proteins; TTC3, also known as protein DCRR1, TPR repeat protein D, TPR repeat protein 3, or RING finger protein 105 (RNF105), is an E3 ubiquitin-protein ligase encoded by a gene within the Down syndrome (DS) critical region on chromosome 21. It affects differentiation and Golgi compactness in neurons through specific actin-regulating pathways. It inhibits the neuronal-like differentiation of pheocromocytoma cells by activating RhoA and by binding to Citron proteins. TTC3 is an Akt-specific E3 ligase that binds to phosphorylated Akt and facilitates its ubiquitination and degradation within the nucleus. It contains four N-terminal TPR motifs, a potential coiled-coil region and a Citron binding region in the central part, and a C-terminal C3H2C2-type RING-H2 finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|.
gi 21313294 335 CTICQAEFQKPVL--LFCQHIFCEECITLWFNREKTCPLCR 373
Cdd:cd16481   2 CIICHDDLKPDQLakLECGHIFHKECIKQWLKEQSTCPTCR 42

RING finger, H2 subclass, found in RING finger protein 11 (RNF11) and similar proteins; RNF11 is an E3 ubiquitin-protein ligase that acts both as an adaptor and a modulator of itch-mediated control of ubiquitination events underlying membrane traffic. It acts downstream of an enzymatic cascade for the ubiquitination of specific substrates. It is also a molecular adaptor of homologous to E6-associated protein C-terminus (HECT)-type ligases. RNF11 has been implicated in the regulation of several signaling pathways. It enhances transforming growth factor receptor (TGFR) signaling by both abrogating Smurf2-mediated receptor ubiquitination and by promoting the Smurf2-mediated degradation of AMSH (associated molecule with the SH3 domain of STAM), a de-ubiquitinating enzyme that enhances TGF-beta signaling and epidermal growth factor receptor (EGFR) endosomal recycling. It also acts directly on Smad4 to enhance Smad4 function, and plays a role in prolonged TGF-beta signaling. RNF11 also functions as a critical component of the A20 ubiquitin-editing protein complex that negatively regulates tumor necrosis factor (TNF)-mediated nuclear factor (NF)-kappaB activation. It interacts with Smad anchor for receptor activation (SARA) and the endosomal sorting complex required for transport (ESCRT)-0 complex, thus participating in the regulation of lysosomal degradation of EGFR. RNF11 acts as a novel GGA cargo actively participating in regulating the ubiquitination of the GGA protein family. RNF11 functions together with TAX1BP1 to target TANK-binding kinase 1 (TBK1)/IkappaB kinase IKKi, and further restricts antiviral signaling and type I interferon (IFN)-beta production. RNF11 contains an N-terminal PPPY motif that binds WW domain-containing proteins such as AIP4/itch, Nedd4 and Smurf1/2 (SMAD-specific E3 ubiquitin-protein ligase 1/2), and a C-terminal C3H2C3-type RING-H2 finger that functions as a scaffold for the coordinated transfer of ubiquitin to substrate proteins together with the E2 enzymes UbcH527 and Ubc13.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|.
gi 21313294 335 CTICQAEFQKPVL---LFCQHIFCEECITLWFNREKTCPLC 372
Cdd:cd16468   2 CVICMADFVVGDPiryLPCMHIYHVDCIDDWLMRSFTCPSC 42

Variant RING finger, HC subclass (C4C4-type), found in retinoblastoma-binding protein 6 (RBBP6) and similar proteins; RBBP6, also known as proliferation potential-related protein, protein P2P-R, retinoblastoma-binding Q protein 1 (RBQ-1), or p53-associated cellular protein of testis (PACT), is a nuclear E3 ubiquitin-protein ligase involved in multiple processes, such as the control of gene expression, mitosis, cell differentiation, and cell apoptosis. It plays a role in both promoting and inhibiting apoptosis in many human cancers, including esophageal, lung, hepatocellular, and colon cancers, familial myeloproliferative neoplasms, as well as in human immunodeficiency virus-associated nephropathy (HIVAN). It functions as an Rb- and p53-binding protein that plays an important role in chaperone-mediated ubiquitination and possibly in protein quality control. It acts as a scaffold protein to promote the assembly of the p53/TP53-MDM2 complex, resulting in an increase of MDM2-mediated ubiquitination and degradation of p53/TP53, and leading to both apoptosis and cell growth. It is also a double-stranded RNA-binding protein that plays a role in mRNA processing by regulating the human polyadenylation machinery and modulating expression of mRNAs with AU-rich 3' untranslated regions (UTRs). Moreover, RBBP6 ubiquitinates and destabilizes the transcriptional repressor ZBTB38 that negatively regulates transcription and levels of the MCM10 replication factor on chromatin. Furthermore, RBBP6 is involved in tunicamycin-induced apoptosis by mediating protein kinase (PKR) activation. RBBP6 contains an N-terminal ubiquitin-like domain and a C4C4-type RING finger, whose overall folding is similar to that of the typical C3HC4-type RING-HC finger. RBBP6 interacts with chaperones Hsp70 and Hsp40 through its N-terminal ubiquitin-like domain. It promotes the ubiquitination of p53 by Hdm2 in an E4-like manner through its RING finger. It also interacts directly with the pro-proliferative transcription factor Y-box-binding protein-1 (YB-1) via its RING finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*
gi 21313294 334 ICTICQAEFQKPVLL-FCQHIFCEECI-TLWFNREKTCPLCRTVI 376
Cdd:cd16620   5 KCPICKDLMKDAVLTpCCGNSFCDECIrTALLEEDFTCPTCKEPD 49

Zinc finger, C3HC4 type (RING finger); The C3HC4 type zinc-finger (RING finger) is a cysteine-rich domain of 40 to 60 residues that coordinates two zinc ions, and has the consensus sequence: C-X2-C-X(9-39)-C-X(1-3)-H-X(2-3)-C-X2-C-X(4-48)-C-X2-C where X is any amino acid. Many proteins containing a RING finger play a key role in the ubiquitination pathway.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|
gi 21313294   335 CTICQAEFQKPVLLF-CQHIFCEECITLWFNRE-KTCPLC 372
Cdd:pfam00097   1 CPICLEEPKDPVTLLpCGHLFCSKCIRSWLESGnVTCPLC 40

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.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 21313294 329 SDMDGICTICQAEFQKPV---LLFCQHIFCEECITLWFNREKTCPLCRTVI 376
Cdd:cd16682   4 SDTDEKCTICLSMLEDGEdvrRLPCMHLFHQLCVDQWLAMSKKCPICRVDI 54

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.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*.
gi 21313294 331 MDGICTICQAEFQKPVLLFCQHIFCEECIT-LWFNREK--TCPLCR 373
Cdd:cd16594   4 EELTCPICLDYFTDPVTLDCGHSFCRACIArCWEEPETsaSCPQCR 49

H2 subclass of RING (RING-H2) fingers and its variants; The RING finger is a specialized type of Zn-finger of 40 to 60 residues that binds two atoms of zinc. It is defined by the "cross-brace" motif that chelates zinc atoms by eight amino acid residues, typically Cys or His, arranged in a characteristic spacing. Canonical RING motifs have been categorized into two major subclasses, RING-HC (C3HC4-type) and RING-H2 (C3H2C3-type), according to their Cys/His content. There are also many variants of RING fingers: some have different Cys/His patterns while some lack a single Cys or His residue at typical Zn ligand positions (the fourth or eighth zinc ligand is prevalently exchanged for an Asp, which can indeed chelate Zn in a RING finger as well). This family corresponds to the H2 subclass of RING (RING-H2) finger proteins that are characterized by containing C3H2C3-type canonical RING-H2 fingers or noncanonical RING-H2 finger variants, including C4HC3- (RING-CH alias RINGv), C3H3C2-, C3H2C2D-, C3DHC3-, and C4HC2H-type modified RING-H2 fingers. The canonical RING-H2 finger has been defined as C-X2-C-X(9-39)-C-X(1-3)-H-X(2-3)-H-X2-C-X(4-48)-C-X2-C, X is any amino acid and the number of X residues varies in different fingers. It binds two Zn ions in a unique "cross-brace" arrangement, which distinguishes it from tandem zinc fingers and other similar motifs. RING-H2 finger can be found in a group of diverse proteins with a variety of cellular functions, including oncogenesis, development, viral replication, signal transduction, the cell cycle and apoptosis. Many of them are ubiquitin-protein ligases (E3s) that serves as a scaffold for binding to ubiquitin-conjugating enzymes (E2s, also referred to as ubiquitin carrier proteins or UBCs) in close proximity to substrate proteins, which enables efficient transfer of ubiquitin from E2 to the substrates.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 21313294 335 CTICQAEFQKPVLLF---CQHIFCEECITLWF-NREKTCPLCR 373
Cdd:cd16448   1 CVICLEEFEEGDVVRllpCGHVFHLACILRWLeSGNNTCPLCR 43

RING finger, HC subclass, found in tripartite motif-containing proteins TRIM5, TRIM6, TRIM22, TRIM34 and similar proteins; TRIM5, TRIM6, TRIM22, and TRIM34, four 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, 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. TRIM5, also known as RING finger protein 88 (RNF88), is a capsid-specific restriction factor that prevents infection from non-host-adapted retroviruses in a species-specific manner by binding to and destabilizing the retroviral capsid lattice before reverse transcription is completed. Its retroviral restriction activity correlates with the ability to activate TAK1-dependent innate immune signaling. TRIM5 also acts as a pattern recognition receptor that activates innate immune signaling in response to the retroviral capsid lattice. Moreover, TRIM5 plays a role in regulating autophagy through activation of autophagy regulator BECN1 by causing its dissociation from its inhibitors BCL2 and TAB2. It also plays a role in autophagy by acting as a selective autophagy receptor which recognizes and targets HIV-1 capsid protein p24 for autophagic destruction. TRIM6, also known as RING finger protein 89 (RNF89), is an E3-ubiquitin ligase that cooperates with the E2-ubiquitin conjugase UbE2K to catalyze the synthesis of unanchored K48-linked polyubiquitin chains, and further stimulates the interferon-I kappa B kinase epsilon (IKKepsilon) kinase-mediated antiviral response. It also regulates the transcriptional activity of Myc during the maintenance of embryonic stem (ES) cell pluripotency, and may act as a novel regulator for Myc-mediated transcription in ES cells. TRIM22, also known as 50 kDa-stimulated trans-acting factor (Staf-50) or RING finger protein 94 (RNF94), is an E3 ubiquitin-protein ligase that plays an integral role in the host innate immune response to viruses. It has been shown to inhibit the replication of a number of viruses, including HIV-1, hepatitis B, and influenza A. TRIM22 acts as a suppressor of basal HIV-1 long terminal repeat (LTR)-driven transcription by preventing the transcription factor specificity protein 1 (Sp1) binding to the HIV-1 promoter. It also controls FoxO4 activity and cell survival by directing Toll-like receptor 3 (TLR3)-stimulated cells toward type I interferon (IFN) type I gene induction or apoptosis. Moreover, TRIM22 can activate the noncanonical nuclear factor-kappaB (NF-kappaB) pathway by activating I kappa B kinase alpha (IKKalpha). It also regulates nucleotide binding oligomerization domain containing 2 (NOD2)-dependent activation of interferon-beta signaling and nuclear factor-kappaB. TRIM34, also known as interferon-responsive finger protein 1 or RING finger protein 21 (RNF21), may function as antiviral protein that contribute to the defense against retroviral infections.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*.
gi 21313294 335 CTICQAEFQKPVLLFCQHIFCEECITLWFNR------EKTCPLCRT 374
Cdd:cd16591   9 CPICLELLTEPLSLDCGHSFCQACITANHKEsvnqegESSCPVCRT 54

RING finger, HC subclass, found in bifunctional apoptosis regulator (BAR); BAR, also known as RING finger protein 47, was originally identified as an inhibitor of Bax-induced apoptosis. It participates in the block of apoptosis induced by TNF-family death receptors (extrinsic pathway) and mitochondria-dependent apoptosis (intrinsic pathway). BAR is predominantly expressed by neurons in the central nervous system and is involved in the regulation of neuronal survival. It is an endoplasmic reticulum (ER)-associated RING-type E3 ubiquitin ligase that interacts with BI-1 protein and post-translationally regulates its stability, as well as functioning in ER stress. BAR contains an N-terminal C3HC4-type RING-HC finger, a SAM domain, a coiled-coil domain, and a C-terminal transmembrane (TM) domain. This model corresponds to the RING-HC finger responsible for the binding of ubiquitin conjugating enzymes (E2s).

                        10        20        30        40
                ....*....|....*....|....*....|....*....|.
gi 21313294 335 CTICQAEFQKPVLLFCQHIFCEECITLWF--NREKTCPLCR 373
Cdd:cd16497   4 CHCCYDLLVNPTTLNCGHSFCRHCLALWWksSKKTECPECR 44

RING finger, HC subclass, found in Caenorhabditis elegans RING finger protein NHL-1 and similar proteins; NHL-1 functions as an E3 ubiquitin-protein ligase in the presence of both UBC-13 and UBC-1 within the ubiquitin pathway of Caenorhabditis elegans. It acts in chemosensory neurons to promote stress resistance in distal tissues by the transcription factor DAF-16 activation but is dispensable for the activation of heat shock factor 1 (HSF-1). NHL-1 belongs to the TRIM (tripartite motif)-NHL 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 domain, as well as an NHL (named after proteins NCL-1, HT2A and Lin-41 that contain repeats folded into a six-bladed beta propeller) repeat domain positioned C-terminal to the RBCC domain.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*.
gi 21313294 335 CTICQAEFQKPVLLFCQHIFCEE-----CITLwFNREKTCPLCRTV 375
Cdd:cd16524   8 CPICLDRYRRPKLLPCQHTFCLSpclegLVDY-VTRKLKCPECRAE 52

RING finger, HC subclass, found in Candida albicans transcriptional regulator of yeast form adherence 3 (TRY3) and similar proteins; TRY3 acts as a transcription factor required for yeast cell adherence to silicone substrate. It contains a typical C3HC4-type RING-HC finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 21313294 332 DGICTICQAEFQKPVLLFCQHIFCEEC-ITLWFNREKTCPLCR 373
Cdd:cd23137   2 DYACPICMNVAWKPVRLECSHVFCLRClVKAQKQKKDNCPLCR 44

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.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*....
gi 21313294 334 ICTICQAEFQKPVLLFCQHIFCEECITLWFNREKT---CPLCRTVISEC 379
Cdd:cd16543   5 TCSICLDLLKDPVTIPCGHSFCMNCITLLWDRKQGvpsCPQCRESFPPR 53

RING finger, H2 subclass, found in Arabidopsis thaliana RING-type E3 ubiquitin transferase BIG BROTHER (BB) and similar proteins; BB (also known as protein ENHANCER OF DA1-1 or EOD1) is an E3 ubiquitin-protein ligase that limits organ size, and possibly seed size, in a dose-dependent manner. It negatively regulates the duration of cell proliferation in leaves and petals independently of the major phytohormones (e.g. auxin, cytokinin, gibberellin, brassinosteroids, ethylene, abscisic acid, jasmonic acid), probably by targeting growth stimulators for degradation. It limits the proliferation of root meristematic cells. BB polyubiquitinates DA1. It is involved in the promotion of leaf senescence, in addition to its function in restricting plant growth. BB-related is an E3 ubiquitin-ligase probably involved in organ size regulation. Members of this subfamily contain a C3H2C3-type RING-H2 finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|.
gi 21313294 335 CTICQAEFQKP---VLLFCQHIFCEECITLWFNREKTCPLC 372
Cdd:cd23115   7 CVICRLEYEEGedlLTLPCKHCYHSECIQQWLQINKVCPVC 47

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.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|..
gi 21313294 335 CTICQAEF---QKPVLLFCQHIFCEECITLWFNREKTCPLCR 373
Cdd:cd16472   5 CVVCMCDYekrQLLRVLPCSHEFHAKCIDKWLKTNRTCPICR 46

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 21313294 334 ICTICQAEFQKPVLLFCQHIFCEECITLWF-NREKTCPLCRTVIS 377
Cdd:cd16550   2 LCPICLEILVEPVTLPCNHTLCMPCFQSTVeKASLCCPLCRLRIS 46