PHD zinc finger; The plant homeodomain (PHD) finger is a C4HC3 zinc-finger-like motif found in nuclear proteins thought to be involved in epigenetics and chromatin-mediated transcriptional regulation. The PHD finger binds two zinc ions using the so-called 'cross-brace' motif and is thus structurally related to the RING finger and the FYVE finger. It is not yet known if PHD fingers have a common molecular function. Several reports suggest that it can function as a protein-protein interacton domain and it was recently demonstrated that the PHD finger of p300 can cooperate with the adjacent BROMO domain in nucleosome binding in vitro. Other reports suggesting that the PHD finger is a ubiquitin ligase have been refuted as these domains were RING fingers misidentified as PHD fingers.

                           10        20        30        40
                   ....*....|....*....|....*....|....*....|....*....
gi 928108986   144 VCDICQQSHNAARMIFCDRrqCPYAAHLDCLGLAER----PTTFLCPRC 188
Cdd:smart00249   1 YCSVCGKPDDGGELLQCDG--CDRWYHQTCLGPPLLeeepDGKWYCPKC 47

PHD zinc finger; The plant homeodomain (PHD) finger is a C4HC3 zinc-finger-like motif found in nuclear proteins thought to be involved in epigenetics and chromatin-mediated transcriptional regulation. The PHD finger binds two zinc ions using the so-called 'cross-brace' motif and is thus structurally related to the RING finger and the FYVE finger. It is not yet known if PHD fingers have a common molecular function. Several reports suggest that it can function as a protein-protein interacton domain and it was recently demonstrated that the PHD finger of p300 can cooperate with the adjacent BROMO domain in nucleosome binding in vitro. Other reports suggesting that the PHD finger is a ubiquitin ligase have been refuted as these domains were RING fingers misidentified as PHD fingers.

                           10        20        30        40
                   ....*....|....*....|....*....|....*....|....*....
gi 928108986   144 VCDICQQSHNAARMIFCDRrqCPYAAHLDCLGLAER----PTTFLCPRC 188
Cdd:smart00249   1 YCSVCGKPDDGGELLQCDG--CDRWYHQTCLGPPLLeeepDGKWYCPKC 47

PHD-finger; PHD folds into an interleaved type of Zn-finger chelating 2 Zn ions in a similar manner to that of the RING and FYVE domains. Several PHD fingers have been identified as binding modules of methylated histone H3.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|.
gi 928108986  144 VCDICQQSHNAARMIFCDrrQCPYAAHLDCLGLAERPTT-----FLCPRCT 189
Cdd:pfam00628   1 YCAVCGKSDDGGELVQCD--GCDDWFHLACLGPPLDPAEipsgeWLCPECK 49

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 928108986    44 CGICLTEIhrVDNPRgrLNSCDHSFCSYCIKEWAKNTNV-CPLC 86
Cdd:smart00184   1 CPICLEEY--LKDPV--ILPCGHTFCRSCIRKWLESGNNtCPIC 40

Uncharacterized conserved protein, contains RING Zn-finger [General function prediction only];

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|..
gi 928108986   44 CGICLTEIHRVDN--PRGRLNSCDHSFCSYCIKEWAK--NTNVCPLCKARFT 91
Cdd:COG5219  1472 CAICYSVLDMVDRslPSKRCATCKNKFHTRCLYKWFAssARSNCPLCRSEIT 1523

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
                 ....*....|....*....|....*....
gi 928108986  63 SCDHSFCSYCIKEWAKNTNVCPLCKARFT 91
Cdd:cd16535   18 NCSHSFCSYCITEWMKRKKECPICRKPIT 46

PHD zinc finger; The plant homeodomain (PHD) finger is a C4HC3 zinc-finger-like motif found in nuclear proteins thought to be involved in epigenetics and chromatin-mediated transcriptional regulation. The PHD finger binds two zinc ions using the so-called 'cross-brace' motif and is thus structurally related to the RING finger and the FYVE finger. It is not yet known if PHD fingers have a common molecular function. Several reports suggest that it can function as a protein-protein interacton domain and it was recently demonstrated that the PHD finger of p300 can cooperate with the adjacent BROMO domain in nucleosome binding in vitro. Other reports suggesting that the PHD finger is a ubiquitin ligase have been refuted as these domains were RING fingers misidentified as PHD fingers.

                           10        20        30        40
                   ....*....|....*....|....*....|....*....|....*....
gi 928108986   144 VCDICQQSHNAARMIFCDRrqCPYAAHLDCLGLAER----PTTFLCPRC 188
Cdd:smart00249   1 YCSVCGKPDDGGELLQCDG--CDRWYHQTCLGPPLLeeepDGKWYCPKC 47

PHD-finger; PHD folds into an interleaved type of Zn-finger chelating 2 Zn ions in a similar manner to that of the RING and FYVE domains. Several PHD fingers have been identified as binding modules of methylated histone H3.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|.
gi 928108986  144 VCDICQQSHNAARMIFCDrrQCPYAAHLDCLGLAERPTT-----FLCPRCT 189
Cdd:pfam00628   1 YCAVCGKSDDGGELVQCD--GCDDWFHLACLGPPLDPAEipsgeWLCPECK 49

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

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|
gi 928108986  44 CGICLTEIHRvdnpRGRLNSCDHSFCSYCIKEWAKNTNVCPLCKARFTRI 93
Cdd:cd23130    3 CPICLDDPED----EAITLPCLHQFCYTCILRWLQTSPTCPLCKTPVTSI 48

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        50
                 ....*....|....*....|....*....|....*....|....*....|.
gi 928108986  41 ENMCGICLTEIHRVDNPRgRLNSCDHSFCSYCIKEWAK-NTNVCPLCKARF 90
Cdd:cd23121    1 DDCCAICLSDFNSDEKLR-QLPKCGHIFHHHCLDRWIRyNKITCPLCRADL 50

RING finger, HC subclass, found in Saccharomyces cerevisiae increased recombination centers protein 20 (IRC20) and similar proteins; IRC20 is an uncharacterized ATP-dependent helicase that is probably involved in a pathway contributing to genomic integrity. IRC20 contains a typical C3HC4-type RING-HC finger.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....
gi 928108986  44 CGICLTEIHRvdnprGRLNSCDHSFCSYCIKEWAKNTNVCPLCK 87
Cdd:cd23135    6 CSICFSEIRS-----GAILKCGHFFCLSCIASWLREKSTCPLCK 44

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 928108986  44 CGICLTEIHrvDNPRGRLNSCDHSFCSYCIKEWAKNTN-VCPLCK 87
Cdd:cd16448    1 CVICLEEFE--EGDVVRLLPCGHVFHLACILRWLESGNnTCPLCR 43

zinc finger-like protein; Provisional

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 928108986  41 ENMCGICLTEIH--RVDNPR--GRLNSCDHSFCSYCIKEWAKN------TNVCPLCKARFTRI 93
Cdd:PHA02926 170 EKECGICYEVVYskRLENDRyfGLLDSCNHIFCITCINIWHRTrretgaSDNCPICRTRFRNI 232

PHD finger found in the inhibitor of growth (ING) protein family; The ING family includes a group of tumor suppressors, ING1-5, which act as readers and writers of the histone epigenetic code, affecting DNA damage response, chromatin remodeling, cellular senescence, differentiation, cell cycle regulation and apoptosis. They may have a general role in mediating the cellular response to genotoxic stress through binding to and regulating the activities of histone acetyltransferase (HAT) and histone deacetylase (HDAC) chromatin remodeling complexes. All ING proteins contain an N-terminal ING domain and a C-terminal plant homeodomain (PHD) finger.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....
gi 928108986 147 ICQQShNAARMIFCDRRQCPYA-AHLDCLGLAERPT-TFLCPRC 188
Cdd:cd15505    3 ICNQV-SYGEMVACDNPNCPIEwFHFECVGLTAKPKgKWYCPEC 45

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 928108986  44 CGICLTEIhrvDNPRgrLNSCDHSFCSYCIKEWAKNTNVCPLCKARFTR 92
Cdd:cd23148    6 CHICKDLL---KAPM--RTPCNHTFCSFCIRTHLNNDARCPLCKAEVTE 49

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 928108986  44 CGICLTEIHRVdnprgRLNSCDHSFCSYCIKEWAKNTNV-CPLC 86
Cdd:cd16449    3 CPICLERLKDP-----VLLPCGHVFCRECIRRLLESGSIkCPIC 41

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

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....
gi 928108986  44 CGICLTEIHRVDNPRgrLNSCDHSFCSYCIKEWAKNTNVCPLCK 87
Cdd:cd16669    2 CPICLLEFEEGETVK--QLPCKHSFHSDCILPWLGKTNSCPLCR 43

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 928108986  41 ENM-CGICLTEIHRVDNprgrLNSCDHSFCSYCIKEWAKNTNV-CPLCKARFTRI 93
Cdd:cd16503    1 ENLtCSICQDLLHDCVS----LQPCMHNFCAACYSDWMERSNTeCPTCRATVQRV 51

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

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*
gi 928108986  42 NMCGICLTEIHRVDNPRGRLN-----SCDHSFCSYCIKEWA----KNTnvCPLCK 87
Cdd:cd16475    1 NVCAVCGQKLDVDDNEEGIIEktyklSCNHVFHEFCIRGWCivgkKQT--CPYCK 53

Uncharacterized conserved protein, contains RING Zn-finger [General function prediction only];

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|..
gi 928108986   44 CGICLTEIHRVDN--PRGRLNSCDHSFCSYCIKEWAK--NTNVCPLCKARFT 91
Cdd:COG5219  1472 CAICYSVLDMVDRslPSKRCATCKNKFHTRCLYKWFAssARSNCPLCRSEIT 1523

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

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|..
gi 928108986   44 CGICLTEIHRV-----DNPRGR----LNSCDHSFCSYCIKEWAKNTNVCPLC 86
Cdd:pfam12678   3 CAICRNPFMEPcpecqAPGDDEcpvvWGECGHAFHLHCISRWLKTNNTCPLC 54

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 928108986  43 MCGICLTEIHR-VDNPrgrlnsCDHSFCSYCIKEWAKNTNVCPLCKA 88
Cdd:cd16561    4 ECSICLEDLNDpVKLP------CDHVFCEECIRQWLPGQMSCPLCRT 44

RING finger, HC subclass, found in RING finger protein 141 (RNF141) and similar proteins; RNF141, also known as zinc finger protein 230 (ZNF230), is a RING finger protein present primarily in the nuclei of spermatogonia, the acrosome, and the tail of spermatozoa. It may have a broad function during early development of vertebrates. It plays an important role in spermatogenesis, including spermatogenic cell proliferation and sperm maturation, as well as motility and fertilization. It also exhibits DNA binding activity. RNF141/ZNF230 gene mutations may be associated with azoospermia. RNF141 contains a C3HC4-type RING finger domain that may function as an activator module in transcription.

                         10        20
                 ....*....|....*....|....
gi 928108986  64 CDHSFCSYCIKEWAKNTNVCPLCK 87
Cdd:cd16545   17 CAHSYCQKCIDKWSDRHRTCPICR 40

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 928108986  44 CGICLTEIHrvDNPRGRLNSCDHSFCSYCIKEWAKNTNVCPLCKA 88
Cdd:cd23118    3 CTICLEDFE--DGEKLRVLPCQHQFHSECVDQWLRRNPKCPVCRR 45

PHD finger 1 found in nuclear receptor-binding SET domain-containing protein NSD1 and NSD2; NSD1, also termed H3 Lysine-36 and H4 Lysine-20 specific histone-lysine N-methyltransferase, or androgen receptor coactivator 267 kDa protein, or androgen receptor-associated protein of 267 kDa, or H3-K36-HMTase H4-K20-HMTase, or Lysine N-methyltransferase 3B (KMT3B), or NR-binding SET domain-containing protein, is a lysine methyltransferase that preferentially methylates H3 on Lysine36 (H3-K36) and H4 on Lysine20 (H4-K20), which is primarily associated with active transcription. It plays a role in several pathologies, including but not limited to Sotos and Weaver syndromes, acute myeloid leukemia, breast cancer, neuroblastoma, and glioblastoma formation. It can alter transcription by interacting with the protein NSD1-interacting zinc finger protein 1 (NIZP1). It also mitigates caspase-1 activation by listeriolysin o (LLO) in macrophages, and requires functional LLO for the regulation of IL-1beta secretion. Moreover, NSD1 regulates RNA polymerase II (RNAP II) recruitment to bone morphogenetic protein 4 (BMP4). NSD2, also termed histone-lysine N-methyltransferase NSD2, or multiple myeloma SET domain-containing protein (MMSET), or protein trithorax-5 Wolf-Hirschhorn syndrome candidate 1 protein (WHSC1), is overexpressed frequently in the t(4;14) translocation in 15% to 20% of multiple myeloma. It plays important roles in cancer cell proliferation, survival, and tumor growth, by mediating constitutive NF-kappaB signaling via the cytokine autocrine loop. It also enhances androgen receptor (AR)-mediated transcription. The principal chromatin-regulatory activity of NSD2 is dimethylation of histone H3 at lysine 36 (H3K36me2). Both NSD1 and NSD2 contain a catalytic suppressor of variegation, enhancer of zeste and trithorax (SET) domain, two proline-tryptophan-tryptophan-proline (PWWP) domains, five plant homeodomain (PHD) fingers, and an NSD-specific Cys-His rich domain (Cys5HisCysHis). In addition, NSD2 harbors a high mobility group (HMG) box. The SET domain is responsible for histone methyltransferase activity. The PWWP, HMG, and PHD fingers mediate chromatin interaction and recognition of histone marks. This model corresponds to the first PHD finger.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*..
gi 928108986 144 VCDICQQShnaARMIFCDRrQCPYAAHLDCLGLAERPT-TFLCPRCT 189
Cdd:cd15648    1 VCQVCEKP---GELLLCEG-QCCGAFHLDCIGLSEMPSgKFICDECI 43

PHD finger 5 found in nuclear SET domain-containing protein 2 (NSD2); NSD2, also termed histone-lysine N-methyltransferase NSD2, or multiple myeloma SET domain-containing protein (MMSET), or protein trithorax-5 Wolf-Hirschhorn syndrome candidate 1 protein (WHSC1), is overexpressed frequently in the t(4;14) translocation in 15% to 20% of multiple myeloma. It plays important roles in cancer cell proliferation, survival, and tumor growth, by mediating constitutive NF-kappaB signaling via the cytokine autocrine loop. It also enhances androgen receptor (AR)-mediated transcription. The principal chromatin-regulatory activity of NSD2 is dimethylation of histone H3 at lysine 36 (H3K36me2). NSD2 contains a catalytic suppressor of variegation, enhancer of zeste and trithorax (SET) domain, two proline-tryptophan-tryptophan-prolin motif (PWWP) domains, a high mobility group (HMG) box, five PHD (plant-homeodomain) zinc fingers, and an NSD-specific Cys-His rich domain (Cys5HisCysHis). The SET domain is responsible for histone methyltransferase activity. The PWWP, HMG, and PHD fingers mediate chromatin interaction and recognition of histone marks. This model corresponds to the fifth PHD finger.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|
gi 928108986 148 CQQSHNAARMIFCDRRQCPYAAHLDCLGLAERP-TTFLCP 186
Cdd:cd15660    2 CFRCGDGGQLVLCDRKSCTKAYHLSCLGLTKRPfGKWECP 41

PHD finger 1 found in nuclear receptor-binding SET domain-containing (NSD) proteins; The nuclear receptor binding SET domain (NSD) protein is a family of three HMTases, NSD1, NSD2/MMSET/WHSC1, and NSD3/WHSC1L1, that are critical in maintaining chromatin integrity. Reducing NSD activity through specific lysine-HMTase inhibitors appears promising to help suppress cancer growth. NSD proteins have specific mono- and dimethylase activities for H3K36, and they non-redundant roles during development. NSD1 plays a role in several pathologies, including but not limited to Sotos and Weaver syndromes, acute myeloid leukemia, breast cancer, neuroblastoma, and glioblastoma formation. NSD2 is involved in cancer cell proliferation, survival, and tumor growth, by mediating constitutive NF-kappaB signaling via the cytokine autocrine loop. NSD3 is amplified in human breast cancer cell lines. Moreover, translocation resulting in NUP98 fusion to NSD3 leads to the development of acute myeloid leukemia. NSD proteins contain a catalytic suppressor of variegation, enhancer of zeste and trithorax (SET) domain, two proline-tryptophan-tryptophan-proline (PWWP) domains, five plant homeodomain (PHD) fingers, and an NSD-specific Cys-His rich domain (Cys5HisCysHis). This model corresponds to the first PHD finger.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*..
gi 928108986 144 VCDICQQSHNaarMIFCdRRQCPYAAHLDCLGLAERP-TTFLCPRCT 189
Cdd:cd15564    1 VCQICEKPGK---LLTC-EGPCCGHFHLDCLGLSEQPdEPFKCDECT 43

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

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*
gi 928108986  41 ENMCGICLTEIHRVDNprGRLNS--CDHSFCSYCIKEWAKNTN-VCPLCKARFTR 92
Cdd:cd16450    2 GNTCPICFEPWTSSGE--HRLVSlkCGHLFGYSCIEKWLKGKGkKCPQCNKKAKR 54

p28-like protein; Provisional

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|
gi 928108986  44 CGICLTEI---HRVDNPRGRLNSCDHSFCSYCIKEWAK---NTNVCPLCKARFTRIYTLN 97
Cdd:PHA03096 181 CGICLENIkakYIIKKYYGILSEIKHEFNIFCIKIWMTeslYKETEPENRRLNTVIVFIE 240

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

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*
gi 928108986  43 MCGICLTEIhrvdnPRGRLNSCDHSFCSYCIKEWAKNTNVCPLCK 87
Cdd:cd16504    4 LCPICFDII-----KEAFVTKCGHSFCYKCIVKHLEQKNRCPKCN 43

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 928108986  42 NMCGICLTEIhrVDNPRGRLNSCDHSFCSYCIKEW-AKNTNVCPLCK 87
Cdd:cd16665    1 DVCAICLDDY--EEGDKLRILPCSHAYHCKCIDPWlTKNKRTCPVCK 45

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

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 928108986   16 PAQKPVSSP--KSPVAASSPLESAATyenmCGICLTEIhrvDNPRgrLNSCDHSFCSYCIKEWAKNTNVCPLCKARF 90
Cdd:TIGR00599   3 ELDITDSSDwlTTPIPSLYPLDTSLR----CHICKDFF---DVPV--LTSCSHTFCSLCIRRCLSNQPKCPLCRAED 70

RING finger, HC subclass, found in RING finger protein 125 (RNF125); RNF125, also known as T-cell RING activation protein 1 (TRAC-1), is an E3 ubiquitin-protein ligase that is predominantly expressed in lymphoid cells, and functions as a positive regulator of T cell activation. It also down-modulates HIV replication and inhibits pathogen-induced cytokine production. It negatively regulates type I interferon signaling, which conjugates Lys(48)-linked ubiquitination to retinoic acid-inducible gene-I (RIG-I) and subsequently leads to the proteasome-dependent degradation of RIG-I. Further, RNF125 conjugates ubiquitin to melanoma differentiation-associated gene 5 (MDA5), a family protein of RIG-I. It thus acts as a negative regulator of RIG-I signaling, and is a direct target of miR-15b in the context of Japanese encephalitis virus (JEV) infection. Moreover, RNF125 binds to and ubiquitinates JAK1, prompting its degradation and inhibition of receptor tyrosine kinase (RTK) expression. It also negatively regulates p53 function through physical interaction and ubiquitin-mediated proteasome degradation. Mutations in RNF125 may lead to overgrowth syndromes (OGS). RNF125, together with three closely related proteins: RNF114, RNF138 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). The UIM of RNF125 binds K48-linked poly-ubiquitin chains and is, together with the RING domain, required for auto-ubiquitination.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|
gi 928108986  44 CGICLTEIHRVDNPRgrlnsCDHSFCSYCIKEWAKNTN-VCPLCKARFTR 92
Cdd:cd16542    4 CAVCLEVLHQPVRTR-----CGHVFCRPCIATSLRNNTwTCPYCRAYLSS 48

Modified RING finger, HC subclass (C3HC3D-type), found in SR-related and CTD-associated factor 11 (SCAF11) and similar proteins; SCAF11, also known as CTD-associated SR protein 11 (CASP11), renal carcinoma antigen NY-REN-40, SC35-interacting protein 1 (Sip1), Serine/arginine-rich splicing factor 2 (SRSF2)-interacting protein, or splicing regulatory protein 129 (SRrp129), is a novel arginine-serine-rich (RS) domain-containing protein essential for pre-mRNA splicing. It functions as an auxiliary splice factor interacting with the spliceosomal component SC35, promoting RNAPII elongation. In addition to SR proteins, such as SC35, ASF/SF2, SRp75, and SRp20, SCAF11 also associates with U1-70K and U2AF65, proteins associated with 5' and 3' splice sites, respectively. SCAF11 contains an N-terminal modified C3HC3D-type RING-HC finger, an internal serine-arginine rich domain (SR domain), and a C-terminal SRI domain.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|.
gi 928108986  44 CGICLTEIHRVDnpRGRLNSCDHSFCSYCIKEWAKNTNVCPLCKARFTRIY 94
Cdd:cd16636    3 CPICLNCLLEQE--VAFPENCSHVFCLTCILKWAETVTSCPIDRKPFQAVY 51

RING finger, H2 subclass, found in RING finger protein 139 (RNF139) and similar proteins; RNF139, also known as translocation in renal carcinoma on chromosome 8 protein (TRC8), is an endoplasmic reticulum (ER)-resident multi-transmembrane protein that functions as a potent growth suppressor in mammalian cells, inducing G2/M arrest, decreased DNA synthesis and increased apoptosis. It is a tumor suppressor that has been implicated in a novel regulatory relationship linking the cholesterol/lipid biosynthetic pathway with cellular growth control. A mutation in RNF139 has been identified in families with hereditary renal (RCC) and thyroid cancers. RNF139 physically and functionally interacts with von Hippel-Lindau (VHL), which is part of an SCF related E3-ubiquitin ligase complex with "gatekeeper" function in renal carcinoma and is defective in most sporadic clear-cell renal cell carcinomas (ccRCC). It suppresses growth and functions with VHL in a common pathway. RNF139 also suppresses tumorigenesis by targeting heme oxygenase-1 for ubiquitination and degradation. Moreover, RNF139 is a target of Translin (TSN), a posttranscriptional regulator of genes transcribed by the transcription factor CREM-tau in postmeiotic male germ cells, suggesting a role of RNF139 in dysgerminoma. In addition, RNF139 forms an integral part of a novel multi-protein ER complex, containing MHC I, US2, and signal peptide peptidase, which is associated with the ER-associated degradation (ERAD) pathway. It is required for the ubiquitination of MHC class I molecules before dislocation from the ER. As a novel sterol-sensing ER membrane protein, RNF139 hinders sterol regulatory element-binding protein-2 (SREBP-2) processing through interaction with SREBP-2 and SREBP cleavage-activated protein (SCAP), regulating its own turnover rate via its E3 ubiquitin ligase activity. RNF139 shows two regions of similarity with the receptor for sonic hedgehog (SHH), Patched. The first region corresponds to the second extracellular domain of Patched, which is involved in binding SHH. The second region is a putative sterol-sensing domain (SSD). The C-terminal half of RNF139 contains a C3H2C3-type RING-H2 finger with E3-ubiquitin ligase activity in vitro.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*....
gi 928108986  41 ENMCGICLTEIHRvdnpRGRLNSCDHSFCSYCIKEWAKNTNVCPLCKAR 89
Cdd:cd16683    4 DDVCAICYQEFTT----SARITPCNHYFHALCLRKWLYIQDTCPMCHQK 48

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 928108986  44 CGICLTEIHRVDNPRgrLNSCDHSFCSYCIKEWAKNTNVCPLCK 87
Cdd:cd16454    2 CAICLEEFKEGEKVR--VLPCNHLFHKDCIDPWLEQHNTCPLCR 43

RING finger, H2 subclass, found in RING finger protein 167 (RNF167) and similar proteins; RNF167, also known as RING105, is an endosomal/lysosomal E3 ubiquitin-protein ligase involved in alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) ubiquitination. It ubiquitinates AMPA-type glutamate receptor subunit GluA2 and regulates its surface expression, and thus acts as a selective regulator of AMPAR-mediated neurotransmission. 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. RNF167 is widely conserved in metazoans and contains an N-terminal signal peptide, a protease-associated (PA) domain, two transmembrane domains (TM1 and TM2), and a C-terminal C3H2C3-type RING-H2 finger domain followed by a putative PEST sequence.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*..
gi 928108986  42 NMCGICLTEIHRVDnpRGRLNSCDHSFCSYCIKEWAKNT-NVCPLCK 87
Cdd:cd16797    1 DVCAICLDEYEEGD--KLRVLPCSHAYHSKCVDPWLTQTkKTCPVCK 45

RING-finger-containing E3 ubiquitin ligase [Signal transduction mechanisms];

                         10        20        30
                 ....*....|....*....|....*....|
gi 928108986  61 LNSCDHSFCSYCIKEWAKNTNVCPLCKARF 90
Cdd:COG5432   40 ETTCGHTFCSLCIRRHLGTQPFCPVCREDP 69

modified RING finger, H2 subclass (C3H2C2D-type), found in RING-box protein 1 (RBX1) and similar proteins; RBX1, also known as Hrt1, protein ZYP, RING finger protein 75 (RNF75), or regulator of cullins 1 (ROC1), is an E3 ubiquitin-protein ligase necessary for ubiquitin ligation activity of multimeric cullin (Cul)-RING E3 ligases (CRLs). RBX1-containing CRLs are involved in the NEDD8 pathway; RBX1 specifically regulates NEDD8ylation of Cul1-4. It can also bind and activate HIV-1 Vif-Cullin5 E3 ligase complex in vitro. Moreover, RBX1 is an essential element of Skp1/Cullin/F-box (SCF) E3-ubiquitin ligase complexes that target diverse proteins for proteasome-mediated degradation. It is a direct functional target of miR-194 and plays an important role in proliferation and migration of gastric cancer (GC) cells. RBX1 is also an essential component of KEAP1/CUL3/RBX1 E3-ubiquitin ligase complex that functions as a regulator of NFE2-related factor 2 (NRF2) and plays a key role in NRF2 pathway deregulation in multiple tumor types, including ovarian carcinomas (OVCA) and papillary thyroid carcinoma (PTC). Furthermore, RBX1 associates with DDB1, Cul4A, and Fbxw5 to form the Fbxw5-DDB1-Cul4A-Rbx1 complex that may function as a dual SUMO/ubiquitin ligase suppressing c-Myb activity through sumoylation or ubiquitination. RBX1 contains a C-terminal modified RING-H2 finger that is of C3H2C2D-type, rather than the canonical C3H2C3-type. The modified RING-H2 finger is essential for its ligase activity.

                         10        20
                 ....*....|....*....|...
gi 928108986  64 CDHSFCSYCIKEWAKNTNVCPLC 86
Cdd:cd16485   36 CNHAFHFHCISRWLKTRQVCPLD 58

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.

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                 ....*....|....*....|....*....|....*....|....*...
gi 928108986  44 CGICLTEIHrvdNPRGRLnsCDHSFCSYCIKEWAK---NTNVCPLCKA 88
Cdd:cd16745    3 CNICLDLAQ---DPVVTL--CGHLFCWPCLHKWLRrqsSQPECPVCKA 45

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
                 ....*....|....*....|..
gi 928108986  64 CDHSFCSYCIKEWAKNTNVCPL 85
Cdd:cd16634   20 CEHAFCNACITEWLSRQQTCPV 41

RING finger, HC subclass, found in RING finger protein 146 (RNF146) and similar proteins; RNF146, also known as dactylidin, or iduna, is a cytoplasmic E3 ubiquitin-protein ligase that is responsible for PARylation-dependent ubiquitination (PARdU). It displays neuroprotective property due to its inhibition of Parthanatos, a PAR dependent cell death, via binding with Poly(ADP-ribose) (PAR). It also modulates PAR polymerase-1 (PARP-1)-mediated oxidative cell injury in cardiac myocytes. Moreover, RNF146 mediates tankyrase-dependent degradation of axin, thereby positively regulating Wnt signaling. It also facilitates DNA repair and protects against cell death induced by DNA damaging agents or gamma-irradiation by translocating to the nucleus after cellular injury and promoting the ubiquitination and degradation of various nuclear proteins involved in DNA damage repair. Furthermore, RNF146 is implicated in neurodegenerative disease and cancer development. It regulates the development and progression of non-small cell lung cancer (NSCLC) by enhancing cell growth, invasion, and survival. RNF146 contains an N-terminal C3HC4-type RING-HC finger followed by a WWE domain with a poly(ADP-ribose) (PAR) binding motif at the tail.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*
gi 928108986  44 CGICL-TEIHRVDNPrgrlnsCDHSFCSYCIKEWAKNTNVCPLCK 87
Cdd:cd16546    3 CPICLqTCIHPVKLP------CGHIFCYLCVKGVAWQSKRCALCR 41

RING finger, H2 subclass, found in RING finger protein 13 (RNF13) and similar proteins; RNF13 is a widely expressed membrane-associated E3 ubiquitin-protein ligase that is functionally significant 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. It functions as an important regulator of inositol-requiring transmembrane kinase/endonuclease IRE1alpha, mediating endoplasmic reticulum (ER) stress-induced apoptosis through the activation of the IRE1alpha-TRAF2-JNK signaling pathway. Moreover, RNF13 is involved in the regulation of the soluble N-ethylmaleimide-sensitive fusion protein attachment protein receptor (SNARE) complex via the ubiquitination of snapin, a SNAP25-interacting protein, which thereby controls synaptic function. In addition, RNF13 participates in regulating the function of satellite cells by modulating cytokine composition. RNF13 is evolutionarily conserved among many metazoans and 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        50
                 ....*....|....*....|....*....|....*....|....*....|..
gi 928108986  42 NMCGICLTEIHrvDNPRGRLNSCDHSFCSYCIKEW-AKNTNVCPLCKARFTR 92
Cdd:cd16796    9 DVCAICLDEYE--EGDKLRILPCSHAYHCKCVDPWlTKTKKTCPVCKQKVVP 58

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 928108986  44 CGICLTEIHrvDNPRGRLNsCDHSFCSYCIKEWAKNTNVCPLC 86
Cdd:cd16481    2 CIICHDDLK--PDQLAKLE-CGHIFHKECIKQWLKEQSTCPTC 41

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

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....
gi 928108986  43 MCGICLTE-IHRVDNPrgrlnsCDHSFCSYCIKEWAKNTNVCPL 85
Cdd:cd16637    3 TCHICLQPlVEPLDTP------CGHTFCYKCLTNYLKIQQCCPL 40

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

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*.
gi 928108986  42 NMCGICLTEIHRVdnprgRLNSCDHSFCSYCIKEWAKNTNVCPLCK 87
Cdd:cd16532    1 DICPICQDEFKDP-----VVLRCKHIFCEDCVSEWFERERTCPLCR 41

Modified RING finger, HC subclass (C4C4-type), found in tripartite motif-containing protein 37 (TRIM37) and similar proteins; TRIM37, also known as mulibrey nanism protein, or MUL, is a peroxisomal E3 ubiquitin-protein ligase that is involved in the tumorigenesis of several cancer types, including pancreatic ductal adenocarcinoma (PDAC), hepatocellular carcinoma (HCC), breast cancer, and sporadic fibrothecoma. It mono-ubiquitinates histone H2A, a chromatin modification associated with transcriptional repression. Moreover, TRIM37 possesses anti-HIV-1 activity, and interferes with viral DNA synthesis. Mutations in the human TRIM37 gene (also known as MUL) cause Mulibrey (muscle-liver-brain-eye) nanism, a rare growth disorder of prenatal onset characterized by dysmorphic features, pericardial constriction, and hepatomegaly. TRIM37 belongs to the C-VIII 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 C4C4-type RING finger, whose overall folding is similar to that of the typical C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region, as well as a MATH (meprin and TRAF-C homology) domain positioned C-terminal to the RBCC domain. Its MATH domain has been shown to interact with the TRAF (TNF-Receptor-Associated Factor) domain of six known TRAFs in vitro.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....
gi 928108986  44 CGIClteIHRVDNPRgRLNSCDHSFCSYCIKEW-AKNTNVCPLC 86
Cdd:cd16619    3 CFIC---MEKLRDPR-LCPHCSKLFCKGCIRRWlSEQRSSCPHC 42