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 18416834  42 CCAICLDTIPLqETAMVKGCEHAYCVTCILRWASYkeKPTCPQCKLPF 89
Cdd:cd16574   3 SCPICLDRFEN-EKAFLDGCFHAFCFTCILEWSKV--KNECPLCKQPF 47

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 18416834  42 CCAICLDTIPLqETAMVKGCEHAYCVTCILRWASYkeKPTCPQCKLPF 89
Cdd:cd16574   3 SCPICLDRFEN-EKAFLDGCFHAFCFTCILEWSKV--KNECPLCKQPF 47

N1R/p28-like protein; Provisional

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*
gi 18416834   43 CAICLDTIPLQET-----AMVKGCEHAYCVTCILRWAsyKEKPTCPQCKLPFDFL 92
Cdd:PHA02929 177 CAICMEKVYDKEIknmyfGILSNCNHVFCIECIDIWK--KEKNTCPVCRTPFISV 229

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

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 18416834  11 EKQVDVLPLQDQDEKKTPqVFNELSFGNHGGC-CAICLDTIPLQETAMVKGCEHAYCVTCILRW-ASYKEKptCPQCKLP 88
Cdd:COG5540 294 YSSSEAIPTTTTKGSLKP-LSIERAVEADKGVeCAICMSNFIKNDRLRVLPCDHRFHVGCVDKWlLGYSNK--CPVCRTA 370

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 18416834  42 CCAICLDTIPLqETAMVKGCEHAYCVTCILRWASYkeKPTCPQCKLPF 89
Cdd:cd16574   3 SCPICLDRFEN-EKAFLDGCFHAFCFTCILEWSKV--KNECPLCKQPF 47

Ring finger domain;

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....
gi 18416834    43 CAICLDTIPLQETAMVKGCEHAYCVTCILRWasYKEKPTCPQCK 86
Cdd:pfam13639   3 CPICLEEFEEGDKVVVLPCGHHFHRECLDKW--LRSSNTCPLCR 44

N1R/p28-like protein; Provisional

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*
gi 18416834   43 CAICLDTIPLQET-----AMVKGCEHAYCVTCILRWAsyKEKPTCPQCKLPFDFL 92
Cdd:PHA02929 177 CAICMEKVYDKEIknmyfGILSNCNHVFCIECIDIWK--KEKNTCPVCRTPFISV 229

Modified RING finger, HC subclass (C3HC3D-type), found in PHD and RING finger domain-containing protein 1 (PHRF1) and similar proteins; PHRF1, also known as KIAA1542, or CTD-binding SR-like protein rA9, is a ubiquitin ligase which induces the ubiquitination of TGIF (TG-interacting factor) at lysine 130. It acts as a tumor suppressor that promotes the transforming growth factor (TGF)-beta cytostatic program through selective release of TGIF-driven promyelocytic leukemia protein (PML) inactivation. PHRF1 contains a plant homeodomain (PHD) finger and a modified C3HC3D-type RING-HC finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|.
gi 18416834  43 CAICLDTIPLQETAMVKGCEHAYCVTCILRWAsyKEKPTCP 83
Cdd:cd16635   7 CPICLNTFRDQAVGTPESCDHIFCLDCILEWS--KNANTCP 45

RING finger, HC subclass, found in Saccharomyces cerevisiae POB3/SPT16 histone-associated protein 1 (ScPSH1) and similar proteins; ScPSH1 is a Cse4-specific E3 ubiquitin ligase that interacts with the kinetochore protein Pat1 and targets the degradation of budding yeast centromeric histone H3 variant, CENP-ACse4, which is essential for faithful chromosome segregation. ScPSH1 contains a C3HC4-type RING-HC finger and a DNA directed RNA polymerase domain.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....
gi 18416834  43 CAICLDTIplqETAMVKGCEHAYCVTCILRWASYKEKPTCPQCK 86
Cdd:cd16568   7 CIICHEYL---YEPMVTTCGHTYCYTCLNTWFKSNRSLSCPDCR 47

RING finger, H2 subclass, found in Arabidopsis thaliana protein SUGAR INSENSITIVE 3 (SIS3) and similar proteins; SIS3 is an E3 ubiquitin-protein ligase that acts as a positive regulator of sugar signaling during early seedling development. SIS3 contains a C3H2C3-type RING-H2 finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*
gi 18416834  43 CAICLDTIPLQETAMVKGCEHAYCVTCILRWasYKEKPTCPQCKL 87
Cdd:cd23118   3 CTICLEDFEDGEKLRVLPCQHQFHSECVDQW--LRRNPKCPVCRR 45

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

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*
gi 18416834  42 CCAICLDTIPLQETAMVKGCEHAYCVTCILRWasYKEKPTCPQCK 86
Cdd:cd16454   1 TCAICLEEFKEGEKVRVLPCNHLFHKDCIDPW--LEQHNTCPLCR 43

RING finger, HC subclass, found in makorin-4 (MKRN4) and similar proteins; MKRN4, also known as makorin RING finger protein pseudogene 4, makorin RING finger protein pseudogene 5, RING finger protein 64 (RNF64), zinc finger protein 127-Xp (ZNF127-Xp), or zinc finger protein 127-like 1, is a new divergent member of the makorin protein family in vertebrates. It may have an ancestral gonad-specific function and maternal embryonic expression before duplication in vertebrates. MKRN4 contains typical arrays of one to four C3H1-type zinc fingers, a motif rich in Cys and His residues (CH) and a C3HC4-type RING-HC finger. The RING-HC finger of mammalian MKRN4 shows high sequence similarity with that of MKRN3, and is not included in this model.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 18416834  43 CAICLDTIPLQETA------MVKGCEHAYCVTCILRWASYKE-----KPTCPQCKL 87
Cdd:cd16732   4 CGICMDKVYEKAHAkervfgILPNCNHAFCVGCIKKWRKSKDfqnevIKACPQCRV 59

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

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*....
gi 18416834  42 CCAICLDTIPLQETAMVKG-CEHAYCVTCILRWASYKeKPTCPQCKLPF 89
Cdd:cd23121   3 CCAICLSDFNSDEKLRQLPkCGHIFHHHCLDRWIRYN-KITCPLCRADL 50

RING finger, HC subclass, found in protein Deltex-3-like (DTX3L) and similar proteins; DTX3L, also known as B-lymphoma- and BAL-associated protein (BBAP) or Rhysin-2 (Rhysin2), is a RING-domain E3 ubiquitin-protein ligase that 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. DTX3L has a unique N-terminus, but lacks the highly basic N-terminal motif and the central proline-rich motif present in other Deltex (DTX) family members, such as DTX1, DTX2, and DTX4. Moreover, its C-terminal region is highly homologous to DTX3. It includes a C3HC4-type RING-HC finger, and a previously unidentified C-terminal domain. DTX3L can associate with DTX1 through its unique N-terminus and further enhance self-ubiquitination.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*..
gi 18416834  41 GCCAICLDTIplQETAMVKGCEHAYCVTCILRwaSYKEKPTCPQCKL 87
Cdd:cd16712   4 DECPICMDRI--SNKKVLPKCKHVFCAACIDK--AMKYKPVCPVCGT 46

RING finger, HC subclass, found in the makorin (MKRN) proteins; The MKRN protein subfamily includes ribonucleoproteins that are characterized by a variety of zinc-finger motifs, including typical arrays of one to four C3H1-type zinc fingers and a C3HC4-type RING-HC finger. Another motif rich in Cys and His residues (CH), with so far unknown function, is also generally present in MKRN proteins. MKRN proteins may have E3 ubiquitin ligase activity.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 18416834  43 CAICLDTIPLQET--AMVKGCEHAYCVTCILRWASYKEKP-----TCPQC 85
Cdd:cd16521   3 CGICMEVVLEKERrfGILSNCNHVFCLECIREWRSSKDFEnsivrSCPIC 52

RING finger, H2 subclass, found in DAZ (deleted in azoospermia)-interacting protein 3 (DZIP3) and similar proteins; DZIP3, also known as RNA-binding ubiquitin ligase of 138 kDa (RUL138) or 2A-HUB protein, is an RNA-binding E3 ubiquitin-protein ligase that interacts with coactivator-associated arginine methyltransferase 1 (CARM1) and acts as a transcriptional coactivator of estrogen receptor (ER) alpha. It is also a histone H2A ubiquitin ligase that catalyzes monoubiquitination of H2A at lysine 119, functioning as a combinatorial component of the repression machinery required for repressing a specific chemokine gene expression program, critically modulating migratory responses to Toll-like receptors (TLR) activation. DZIP3 contains a C3H2C3-type RING-H2 finger at the C-terminus.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*.
gi 18416834  43 CAICLDTIPLQETAMVKGCEHAYCVTCILRWasYKEKPTCPQCKLP 88
Cdd:cd16460   3 CVICHEAFSDGDRLLVLPCAHKFHTQCIGPW--LDGQQTCPTCRLH 46

RING finger, HC subclass, found in Schizosaccharomyces pombe DNA repair protein Rad8 (SpRad8) and similar proteins; SpRad8 is a conserved protein homologous to Saccharomyces cerevisiae DNA repair protein Rad5 and human helicase-like transcription factor (HLTF) that is required for error-free postreplication repair by contributing to polyubiquitylation of PCNA. SpRad8 contains a C3HC4-type RING-HC finger responsible for the E3 ubiquitin ligase activity, a SNF2-family helicase domain including an ATP binding site, and a family-specific HIRAN domain (HIP116, Rad5p N-terminal domain) that contributes to nuclear localization.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 18416834  43 CAICLDTiPLQETAmVKGCEHAYCVTCILRWASY----KEKPTCPQCKLPFD 90
Cdd:cd16572   7 CPICAEE-PISELA-LTRCWHSACKDCLLDHIEFqkskNEVPLCPTCRQPIN 56

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.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*
gi 18416834  43 CAICLDtiPLQETAMVKgCEHAYCVTCILRWASYKEK--PTCPQC 85
Cdd:cd16536   3 CPICLE--PPVAPRITR-CGHIFCWPCILRYLSLSEKkwRKCPIC 44

RING finger, H2 subclass, found in RING finger proteins, RNF130, RNF149, RNF150 and similar proteins; This subfamily includes RING finger proteins, RNF130, RNF149 and RNF150, which belong to a larger PA-TM-RING ubiquitin ligase family that has been characterized by an N-terminal signal peptide, a protease-associated (PA) domain, a transmembrane (TM) domain and a C-terminal C3H2C3-type RING-H2 finger domain followed by a putative PEST sequence. RNF130, also known as Goliath homolog (H-Goliath), is a paralog of RNF128. It is a transmembrane E3 ubiquitin-protein ligase expressed in leukocytes. It has a self-ubiquitination property and controls the development of T cell clonal anergy by ubiquitination. RNF133 is a testis-specific endoplasmic reticulum-associated E3 ubiquitin ligase that may play a role in sperm maturation through an ER-associated degradation (ERAD) pathway. RNF149, also known as DNA polymerase-transactivated protein 2, is an E3 ubiquitin-protein ligase that induces the ubiquitination of wild-type v-Raf murine sarcoma viral oncogene homolog B1 (BRAF) and promotes its proteasome-dependent degradation. RNF150 polymorphisms may be associated with chronic obstructive pulmonary disease (COPD) risk in the Chinese population. This subfamily also includes Drosophila melanogaster protein goliath (d-goliath), also known as protein g1, which is one of the founding members of the group. It was originally identified as a transcription factor involved in the embryo mesoderm formation.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*.
gi 18416834  42 CCAICLDTIPLQETAMVKGCEHAYCVTCILRWASykEKPTCPQCKL 87
Cdd:cd16668   1 CCAVCIEPYKPSDVIRILPCKHIFHKSCVDPWLL--EHRTCPMCKL 44

RING finger, H2 subclass, found in Arabidopsis thaliana RING-H2 zinc finger protein RHF2A and similar proteins; RHF2A is an E3 ubiquitin-protein ligase involved in the positive regulation of the gametogenesis progression. It is required for the degradation of KRP6, a cyclin-dependent kinase inhibitor which accumulates during meiosis and blocks the progression of subsequent mitoses during gametophytes development. It functions in association with RHF1A. Members of this subfamily contain a C3H2C3-type RING-H2 finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 18416834  43 CAICLDTIPLQETAMVKGCEHAYCVTCILRWASYKEKptCPQC 85
Cdd:cd23122  14 CSICLESFCEADPATVTSCKHEYHLQCILEWSQRSKE--CPMC 54

RING finger, HC subclass, found in Arabidopsis thaliana RING membrane-anchor proteins (AtRMAs) and similar proteins; AtRMAs, including AtRma1, AtRma2, and AtRma3, are endoplasmic reticulum (ER)-localized Arabidopsis homologs of human outer membrane of the ER-anchor E3 ubiquitin-protein ligase, RING finger protein 5 (RNF5). AtRMAs possess E3 ubiquitin ligase activity, and may play a role in the growth and development of Arabidopsis. The AtRMA1 and AtRMA3 genes are predominantly expressed in major tissues, such as cotyledons, leaves, shoot-root junction, roots, and anthers, while AtRMA2 expression is restricted to the root tips and leaf hydathodes. AtRma1 probably functions with the Ubc4/5 subfamily of E2. AtRma2 is likely involved in the cellular regulation of ABP1 expression levels through interacting with auxin binding protein 1 (ABP1). AtRMA proteins contain an N-terminal C3HC4-type RING-HC finger and a trans-membrane-anchoring domain in their extreme C-terminal region.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*
gi 18416834  43 CAICLDTIplqETAMVKGCEHAYCVTCILRW-ASYKEKPTCPQCK 86
Cdd:cd16745   3 CNICLDLA---QDPVVTLCGHLFCWPCLHKWlRRQSSQPECPVCK 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 18416834  42 CCAICLDTIplqETAMVKGCEHAYCVTCILRWASyKEKPTCPQC 85
Cdd:cd16449   2 ECPICLERL---KDPVLLPCGHVFCRECIRRLLE-SGSIKCPIC 41

RING finger, HC subclass, found in Arabidopsis thaliana protein ariadne homolog 6 (ARI6) and similar proteins; This subfamily includes ARI6 and ARI11. They might act as E3 ubiquitin-protein ligases, or as part of E3 complexes, which accept ubiquitin from specific E2 ubiquitin-conjugating enzymes and then transfer it to substrates. Members of this subfamily contain a typical C3HC4-type RING-HC finger.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 18416834  43 CAICLDTIPLQETAMVkGCEHAYCVTCilrWASY-----KEKPTCPQCKLP 88
Cdd:cd23141   4 CGICFESFPVEEMRAA-SCGHYFCKTC---WTGYihtaiSDGPGCLDLRCP 50

RING finger, H2 subclass, found in RING finger protein 130 (RNF130) and similar proteins; RNF130, also known as Goliath homolog (H-Goliath), is a paralog of RNF128, also known as gene related to anergy in lymphocytes protein (GRAIL). It is a transmembrane E3 ubiquitin-protein ligase expressed in leukocytes. It has a self-ubiquitination property, and controls the development of T cell clonal anergy by ubiquitination. RNF130 contains an N-terminal signal peptide, a protease-associated (PA) domain, a transmembrane (TM) domain and a C-terminal C3H2C3-type RING-H2 finger domain followed by a putative PEST sequence.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*
gi 18416834  43 CAICLDTIPLQETAMVKGCEHAYCVTCILRWASykEKPTCPQCKL 87
Cdd:cd16803   3 CAVCIEGYKQNDVVRILPCKHVFHKSCVDPWLN--EHCTCPMCKL 45

RING finger, H2 subclass, found in RING finger protein 13 (RNF13), RING finger protein 167 (RNF167), and similar proteins; This subfamily includes RING finger protein 13 (RNF13), RING finger protein 167 (RNF167), Zinc/RING finger protein 4 (ZNRF4), and similar proteins, which belong to a larger PA-TM-RING ubiquitin ligase family that has been characterized by containing an N-terminal signal peptide, a protease-associated (PA) domain, a transmembrane domain (TM), and a C-terminal C3H2C3-type RING-H2 finger followed by a putative PEST sequence. RNF13 is a widely expressed membrane-associated E3 ubiquitin-protein ligase that functions in the regulation of cancer development, muscle cell growth, and neuronal development. Its expression is developmentally regulated during myogenesis and is upregulated in various tumors. RNF13 negatively regulates cell proliferation through its E3 ligase activity. RNF167, also known as RING105, is an endosomal/lysosomal E3 ubiquitin-protein ligase involved in the ubiquitination of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR). It acts as an endosomal membrane protein which ubiquitylates vesicle-associated membrane protein 3 (VAMP3) and regulates endosomal trafficking. Moreover, RNF167 plays a role in the regulation of TSSC5 (tumor-suppressing subchromosomal transferable fragment cDNA, also known as ORCTL2/IMPT1/BWR1A/SLC22A1L), which can function in concert with the ubiquitin-conjugating enzyme UbcH6. ZNRF4, also known as RING finger protein 204 (RNF204), or Nixin, is an endoplasmic reticulum (ER) membrane-anchored ubiquitin ligase that physically interacts with the ER-localized chaperone calnexin in a glycosylation-independent manner, inducing calnexin ubiquitination, and p97-dependent degradation. The murine protein sperizin (spermatid-specific ring zinc finger) is a homolog of human ZNRF4. It is specifically expressed in Haploid germ cells and is involved in spermatogenesis.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....
gi 18416834  43 CAICLDTIPLQETAMVKGCEHAYCVTCILRWASyKEKPTCPQCK 86
Cdd:cd16665   3 CAICLDDYEEGDKLRILPCSHAYHCKCIDPWLT-KNKRTCPVCK 45

RING finger, HC subclass, found in makorin-1 (MKRN1), makorin-3 (MKRN3), and similar proteins; MKRN1, also known as makorin RING finger protein 1 or RING finger protein 61 (RNF61), is an E3 ubiquitin-protein ligase targeting the telomerase catalytic subunit (TERT) for proteasome processing. It regulates the ubiquitination and degradation of peroxisome-proliferator-activated receptor gamma (PPARgamma), a nuclear receptor that is linked to obesity and metabolic diseases. It also mediates the posttranslational regulation of p14ARF, and thus potentially regulates cellular senescence and tumorigenesis in gastric cancer. Moreover, MKRN1 functions as a differentially negative regulator of p53 and p21, and controls cell cycle arrest and apoptosis. It induces degradation of West Nile virus (WNV) capsid protein to protect cells from WNV. It is a RNA-binding protein involved in the modulation of cellular stress and apoptosis. It predominantly associates with proteins involved in mRNA metabolism including regulators of mRNA turnover, transport, and/or translation, and acts as a component of a ribonucleoprotein complex in embryonic stem cells (ESCs) that is recruited to stress granules upon exposure to environmental stress. MKRN1 interacts with poly(A)-binding protein (PABP), a key component of different ribonucleoprotein complexes, in an RNA-independent manner, and stimulates translation in nerve cells. In addition, MKRN1 is a novel SEREX (serological identification of antigens by recombinant cDNA expression cloning) antigen of esophageal squamous cell carcinoma (SCC). It may be involved in carcinogenesis of the well-differentiated type of tumors possibly via ubiquitination of filamin A interacting protein 1 (L-FILIP). Human MKRN1 contains three N-terminal C3H1-type zinc fingers, a motif rich in Cys and His residues (CH), a C3HC4-type RING-HC finger, and another C3H1-type zinc finger at the C-terminus. MKRN3, also known as makorin RING finger protein 3, RING finger protein 63 (RNF63), or zinc finger protein 127 (ZNF127), is a therian mammal-specific retrocopy of MKRN1. It acts as a putative E3 ubiquitin-protein ligase involved in ubiquitination and cell signaling. MKRN3 shows a potential inhibitory effect on hypothalamic gonadotropin-releasing hormone (GnRH) secretion. Its defects represent the most frequent known genetic cause of familial central precocious puberty (CPP). In contrast to human MKRN1, human MKRN3 lacks the second C3H1-type zinc finger at the N-terminal region. The RING-HC finger of mammalian MKRN4 shows high sequence similarity with that of MKRN3, and is also included in this model.

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                ....*....|....*....|....*....|....*....|....*....|....*.
gi 18416834  43 CAICLDTI------PLQETAMVKGCEHAYCVTCILRWASYKE-----KPTCPQCKL 87
Cdd:cd16730   4 CGICMEVVyekanpSERRFGILSNCNHTYCLKCIRKWRSAKQfeskiIKSCPECRI 59

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

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                ....*....|....*....|....*....|....*....|....*....|...
gi 18416834  38 NHGGCCAICLDTipLQETAMVKG--CEHAYCVTCILRWASyKEKPTCPQCKLP 88
Cdd:cd16473   2 LECEECAICLEN--YQNGDLLRGlpCGHVFHQNCIDVWLE-RDNHCCPVCRWP 51

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.

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                ....*....|....*....|....*....|....*....|....*....|....
gi 18416834  43 CAICLDtiPLQETAMVKgCEHAYCVTCILR-WASYKEKPT------CPQCKLPF 89
Cdd:cd16592   7 CPICLG--YFKDPVILD-CEHSFCRACIARhWGQEAMEGNgaegvfCPQCGEPC 57

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

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                ....*....|....*....|....*....|....*....|....*...
gi 18416834  43 CAICLDTipLQETAMVKgCEHAYCVTCILR-WASYKEKPTCPQCKLPF 89
Cdd:cd16594   8 CPICLDY--FTDPVTLD-CGHSFCRACIARcWEEPETSASCPQCRETC 52

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

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 18416834  11 EKQVDVLPLQDQDEKKTPqVFNELSFGNHGGC-CAICLDTIPLQETAMVKGCEHAYCVTCILRW-ASYKEKptCPQCKLP 88
Cdd:COG5540 294 YSSSEAIPTTTTKGSLKP-LSIERAVEADKGVeCAICMSNFIKNDRLRVLPCDHRFHVGCVDKWlLGYSNK--CPVCRTA 370

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 18416834  43 CAICLDTIPLQETAMVKgCEHAYCVTCILRWasYKEKPTCPQCKLP 88
Cdd:cd16481   2 CIICHDDLKPDQLAKLE-CGHIFHKECIKQW--LKEQSTCPTCRVH 44

RING finger, H2 subclass, found in RING finger protein 24 (RNF24) and similar proteins; RNF24 is an intrinsic membrane protein localized in the Golgi apparatus. It specifically interacts with the ankyrin-repeats domains (ARDs) of TRPC1, -3, -4, -5, -6, and -7, and affects TRPC intracellular trafficking without affecting their activity. RNF24 contains an N-terminal transmembrane domain and a C-terminal C3H2C3-type RING-H2 finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*.
gi 18416834  43 CAICLDTIPLQETAMVKGCEHAYCVTCILRWASYKEkpTCPQCKLP 88
Cdd:cd16675   3 CAVCLEEFKPKDELGICPCKHAFHRKCLIKWLEVRK--VCPLCNMP 46

RING finger, HC subclass, found in SH3 domain-containing RING finger protein 2 (SH3RF2) and similar proteins; SH3RF2, also known as heart protein phosphatase 1-binding protein (HEPP1), plenty of SH3s (POSH)-eliminating RING protein (POSHER), protein phosphatase 1 regulatory subunit 39, or RING finger protein 158 (RNF158), is a putative E3 ubiquitin-protein ligase that acts as an anti-apoptotic regulator for the c-Jun N-terminal kinase (JNK) pathway by binding to and promoting the proteasomal degradation of SH3RF1 (or POSH), a scaffold protein that is required for pro-apoptotic JNK activation. It may also play a role in cardiac functions together with protein phosphatase 1. SH3RF2 contains an N-terminal C3HC4-type RING-HC finger responsible for the E3 ligase activity and four Src Homology 3 (SH3) domains, which are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*.
gi 18416834  43 CAICLDTipLQETAMVKGCEHAYCVTCILRWASYKEKPTCPQCKLP 88
Cdd:cd16749   3 CPVCFEK--LDVTAKVLPCQHTFCKPCLQRIFKARKELRCPECRTP 46

RING finger, HC subclass, found in radiation sensitivity protein 5 (RAD5) and similar proteins; RAD5, also known as revertibility protein 2 (REV2), or DNA repair protein RAD5, is a probable helicase, and a member of the UBC2/RAD6 epistasis group. It functions with the DNA repair protein RAD18 in error-free postreplication DNA repair. It is involved in the maintenance of wild-type rates of instability of simple repetitive sequences such as poly(GT) repeats. It may also be involved in maintaining a balance which acts in favor of error-prone non-homologous joining during DNA double-strand breaks repairs. It recruits the UBC13-MMS2 dimer to chromatin for DNA repair. RAD5 contains a typical C3HC4-type RING-HC finger.

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                ....*....|....*....|....*....|....*....|....*....|...
gi 18416834  43 CAICL-DTIPLQEtAMVKGCEHAYCVTCILRWASYKEK----PTCPQCKLPFD 90
Cdd:cd23131   6 CSICTqEPIEVGE-VVFTECGHSFCEDCLLEYIEFQNKkkldLKCPNCREPIS 57

RING finger, H2 subclass, found in Arabidopsis thaliana protein ABA INSENSITIVE RING PROTEIN 1 (AIRP1) and similar proteins; This subfamily includes Arabidopsis thaliana AIRP1 and RING-H2 finger B1a (RHB1A). AIRP1, also known as RING-type E3 ubiquitin transferase AIRP1, possesses E3 ubiquitin-protein ligase activity in vitro when associated with the E2 enzyme UBC8. It plays combinatory roles with AIRP2 in the positive regulation of the abscisic acid-mediated drought stress response. RHB1A is a probable E3 ubiquitin-protein ligase. Members of this subfamily contain a C3H2C3-type RING-H2 finger.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....
gi 18416834  42 CCAICLDTIPLQETAMVKGCEHAYCVTCILRWasYKEKPTCPQC 85
Cdd:cd23116   4 VCPTCLEGYTEENPKLLTKCGHHFHLACIYEW--MERSERCPVC 45

RING finger, H2 subclass, found in RING finger protein 128 (RNF128) and similar proteins; This subfamily includes RING finger proteins RNF128, RNF133, RNF148, and similar proteins, which belong to a larger PA-TM-RING ubiquitin ligase family that has been characterized by containing an N-terminal signal peptide, a protease-associated (PA) domain, a transmembrane (TM) domain and a C-terminal C3H2C3-type RING-H2 finger followed by a putative PEST sequence. RNF128, also known as gene related to anergy in lymphocytes protein (GRAIL), is a type 1 transmembrane E3 ubiquitin-protein ligase that is a critical regulator of adaptive immunity and development. It inhibits cytokine gene transcription, is expressed in anergic CD4+ T cells, and has been implicated in primary T cell activation, survival, and differentiation, as well as in T cell anergy and oral tolerance. It induces T cell anergy through the ubiquitination activity of its cytosolic RING finger. It regulates expression of the costimulatory molecule CD40L on CD4 T cells, and ubiquitinates the costimulatory molecule CD40 ligand (CD40L) during the induction of T cell anergy. Moreover, RNF128 interacts with the luminal/extracellular portion of both CD151 and the related tetraspanin CD81 via its PA domain, which promoted ubiquitination of cytosolic lysine residues. It also down-modulates the expression of CD83 (previously described as a cell surface marker for mature dendritic cells) on CD4 T cells. Furthermore, Rho guanine dissociation inhibitor (RhoGDI) has been identified as a potential substrate of RNF128, suggesting a role for Rho effector molecules in T cell anergy. In addition, RNF128 plays a role in environmental stress responses. It promotes environmental salinity tolerance in euryhaline tilapia. RNF133 is a testis-specific endoplasmic reticulum-associated E3 ubiquitin ligase that is mainly present in the cytoplasm of elongated spermatids. It may play a role in sperm maturation through an ER-associated degradation (ERAD) pathway. RNF148 is a testis-specific E3 ubiquitin ligase that is abundantly expressed in testes and slightly expressed in pancreas. Its expression is regulated by histone deacetylases.

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                ....*....|....*....|....*....|....*....|....
gi 18416834  43 CAICLDTIPLQETAMVKGCEHAYCVTCILRWasYKEKPTCPQCK 86
Cdd:cd16802   3 CAVCIEPYKPNDVVRILTCNHLFHKNCIDPW--LLEHRTCPMCK 44

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.

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                ....*....|....*....|....*....|....*....|....*....|....*
gi 18416834  43 CAICLD------TIPlqetamvkgCEHAYCVTCI-LRWASYK-EKPTCPQCKLPF 89
Cdd:cd16597   8 CSICLElfkdpvTLP---------CGHNFCGVCIeKTWDSQHgSEYSCPQCRATF 53

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 18416834  42 CCAICLDTIPLQETAMVKGCEHAYCVTCILRWasYKEKPTCPQCK 86
Cdd:cd16465   1 CCPICCSEYVKDEIATELPCHHLFHKPCITAW--LQKSGTCPVCR 43

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 18416834  42 CCAICLDTipLQETAMVKgCEHAYCVTCILRWASYKEKP-TCPQCK 86
Cdd:cd16611   6 HCPLCLDF--FRDPVMLS-CGHNFCQSCITGFWELQAEDtTCPECR 48

RING finger, HC subclass, found in tripartite motif-containing protein TRIM58 and similar proteins; TRIM58, also known as protein BIA2, is an erythroid E3 ubiquitin-protein ligase induced during late erythropoiesis. It binds and ubiquitinates the intermediate chain of the microtubule motor dynein (DYNC1LI1/DYNC1LI2), stimulating the degradation of the dynein holoprotein complex. It may participate in the erythroblast enucleation process through regulation of nuclear polarization. TRIM58 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 18416834  43 CAICLDTipLQETAMVKgCEHAYCVTCILRWASYKEKP-----TCPQCKLPF 89
Cdd:cd16606   5 CPVCLDF--LQEPVSVD-CGHSFCLRCISEFCEKSDSAqggvyACPQCRGPF 53

RING finger, HC subclass, found in BRCA1-associated RING domain protein 1 (BARD-1) and similar proteins; BARD-1 is a critical factor in BRCA1-mediated tumor suppression and may also serve as a target for tumorigenic lesions in some human cancers. It associates with BRCA1 (breast cancer-1) to form a heterodimeric BRCA1/BARD1 complex that is responsible for maintaining genomic stability through nuclear functions involving DNA damage signaling and repair, transcriptional regulation, and cell cycle control. The BRCA1/BARD1 complex catalyzes autoubiquitination of BRCA1 and trans ubiquitination of other protein substrates. Its E3 ligase activity is dramatically reduced in the presence of UBX domain protein 1 (UBXN1). BARD-1 contains an C3HC4-type RING-HC finger that binds BRCA1 at its N-terminus and three tandem ankyrin repeats and tandem BRCT repeat domains at its C-terminus. The BRCT repeats bind CstF-50 (cleavage stimulation factor) to modulate mRNA processing and RNAP II stability in response to DNA damage.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*..
gi 18416834  42 CCAICLDTipLQETAMVKGCEHAYCVTCIlrwASYKEKPtCPQCKLP 88
Cdd:cd16496  17 RCSRCASI--LKEPVTLGGCEHVFCRSCV---GDRLGNG-CPVCDTP 57