IQ (isoleucine-glutamine) motif containing D (IQCD); IQCD, also called dynein regulatory complex protein 10 (DRC10), belongs to the IQ motif-containing protein family which contains a C-terminal conserved IQ motif domain and two coiled-coil domains. The IQ motif ([ILV]QxxxRxxxx[RK]), where x stands for any amino-acid residue, interacts with calmodulin (CaM) in a calcium-independent manner and is present in proteins with a wide diversity of biological functions. The IQCD protein was found to primarily accumulate in the acrosome area of round and elongating spermatids of the testis during late stage of spermiogenesis and was then localized to the acrosome and tail regions of mature spermatozoa. The expression of IQCD follows the trajectory of acrosome development during spermatogenesis. IQCD is associated with neuroblastoma and neurodegenerative diseases, and is reported to interact with the nuclear retinoid X receptor in the presence of 9-cis-retinoic acid, thereby activating the transcriptional activity of the receptor.

                          10        20
                  ....*....|....*....|....*.
gi 2462612425 186 RIKCVTRIQAYWRGCVVRKWYRNLRK 211
Cdd:cd23767     8 MNRAATLIQALWRGYKVRKELKKKKK 33

Ring finger domain;

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....
gi 2462612425 127 CPICKEEFELRPQVL-LSCSHVFHKACLQAFekFTNKKTCPLCR 169
Cdd:pfam13639   3 CPICLEEFEEGDKVVvLPCGHHFHRECLDKW--LRSSNTCPLCR 44

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

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 2462612425 109 EWEKVKQRSLLQGDSVQPCPICKEEFELRpqVLLSCSHVFHKACLQAFekFTNKKTCPLCRKNQYQTR 176
Cdd:COG5432    10 DWNQTKIPSLKGLDSMLRCRICDCRISIP--CETTCGHTFCSLCIRRH--LGTQPFCPVCREDPCESR 73

IQ (isoleucine-glutamine) motif containing D (IQCD); IQCD, also called dynein regulatory complex protein 10 (DRC10), belongs to the IQ motif-containing protein family which contains a C-terminal conserved IQ motif domain and two coiled-coil domains. The IQ motif ([ILV]QxxxRxxxx[RK]), where x stands for any amino-acid residue, interacts with calmodulin (CaM) in a calcium-independent manner and is present in proteins with a wide diversity of biological functions. The IQCD protein was found to primarily accumulate in the acrosome area of round and elongating spermatids of the testis during late stage of spermiogenesis and was then localized to the acrosome and tail regions of mature spermatozoa. The expression of IQCD follows the trajectory of acrosome development during spermatogenesis. IQCD is associated with neuroblastoma and neurodegenerative diseases, and is reported to interact with the nuclear retinoid X receptor in the presence of 9-cis-retinoic acid, thereby activating the transcriptional activity of the receptor.

                          10        20
                  ....*....|....*....|....*.
gi 2462612425 186 RIKCVTRIQAYWRGCVVRKWYRNLRK 211
Cdd:cd23767     8 MNRAATLIQALWRGYKVRKELKKKKK 33

N1R/p28-like protein; Provisional

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|
gi 2462612425 127 CPICKEEFELRP------QVLLSCSHVFHKACLQAFEKftNKKTCPLCRK 170
Cdd:PHA02929  177 CAICMEKVYDKEiknmyfGILSNCNHVFCIECIDIWKK--EKNTCPVCRT 224

RING finger, H2 subclass, found in RING finger protein 32 (RNF32) and similar proteins; RNF32 is mainly expressed in testis spermatogenesis, most likely in spermatocytes and/or in spermatids, suggesting a possible role in sperm formation. RNF32 contains two C3H2C3-type RING-H2 fingers separated by an IQ domain of unknown function. Although the biological function of RNF32 remains unclear, proteins with double RING-H2 fingers may act as scaffolds for binding several proteins that function in the same pathway.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*.
gi 2462612425 126 PCPICKEEFELRPQVLLSCSHVFHKACLQAFEKFTNKK--TCPLCR 169
Cdd:cd16471     1 ECPICLCAFKGRKCTLLSCSHVFHEACLSAFEKFIESKnqKCPLCR 46

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 2462612425 127 CPICKEEFELR-PQVLLSCSHVFHKACLQAFEKFTNkKTCPLCR 169
Cdd:cd16448     1 CVICLEEFEEGdVVRLLPCGHVFHLACILRWLESGN-NTCPLCR 43

Ring finger domain;

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....
gi 2462612425 127 CPICKEEFELRPQVL-LSCSHVFHKACLQAFekFTNKKTCPLCR 169
Cdd:pfam13639   3 CPICLEEFEEGDKVVvLPCGHHFHRECLDKW--LRSSNTCPLCR 44

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

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*
gi 2462612425 127 CPICKEEFEL--RPQVLLSCSHVFHKACLQafEKFTNKKTCPLCR 169
Cdd:cd16461     2 CAICLSDYENgeELRRLPECKHAFHKECID--EWLKSNSTCPLCR 44

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 2462612425 127 CPICKEEFelRPQVLLSCSHVFHKACLQafEKFTNKKTCPLCR 169
Cdd:cd16532     3 CPICQDEF--KDPVVLRCKHIFCEDCVS--EWFERERTCPLCR 41

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 2462612425  127 CPICKEEFELRPqVLLSCSHVFHKACLQAFEKfTNKKTCPLC 168
Cdd:smart00184   1 CPICLEEYLKDP-VILPCGHTFCRSCIRKWLE-SGNNTCPIC 40

RING finger, H2 subclass, found in synoviolin and similar proteins; Synoviolin, also known as synovial apoptosis inhibitor 1 (Syvn1), Hrd1, or Der3, is an endoplasmic reticulum (ER)-anchoring E3 ubiquitin ligase that functions as a suppressor of ER stress-induced apoptosis and plays a role in homeostasis maintenance. It also targets tumor suppressor gene p53 for proteasomal degradation, suggesting crosstalk between ER associated degradation (ERAD) and p53 mediated apoptotic pathway under ER stress. Moreover, synoviolin controls body weight and mitochondrial biogenesis through negative regulation of the thermogenic coactivator peroxisome proliferator-activated receptor coactivator (PGC)-1beta. It upregulates amyloid beta production by targeting a negative regulator of gamma-secretase, Retention in endoplasmic reticulum 1 (Rer1), for degradation. It is also involved in the degradation of endogenous immature nicastrin, and affects amyloid beta-protein generation. Moreover, synoviolin is highly expressed in rheumatoid synovial cells and may be involved in the pathogenesis of rheumatoid arthritis (RA). It functions as an anti-apoptotic factor that is responsible for the outgrowth of synovial cells during the development of RA. It promotes inositol-requiring enzyme 1 (IRE1) ubiquitination and degradation in synovial fibroblasts with collagen-induced arthritis. Furthermore, the upregulation of synoviolin may represent a protective response against neurodegeneration in Parkinson's disease (PD). In addition, synoviolin is involved in liver fibrogenesis. Synoviolin contains a C3H2C2-type RING-H2 finger.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|...
gi 2462612425 127 CPICKEEFELRPQvLLSCSHVFHKACLQAFekFTNKKTCPLCR 169
Cdd:cd16479     4 CIICREEMTVGAK-KLPCGHIFHLSCLRSW--LQRQQTCPTCR 43

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 2462612425 125 QPCPICKEEFELRPQVL-LSCSHVFHKACLQAFekFTNKKTCPLCR 169
Cdd:cd16460     1 TPCVICHEAFSDGDRLLvLPCAHKFHTQCIGPW--LDGQQTCPTCR 44

RING finger, H2 subclass, found in RING finger protein 126 (RNF126) and similar proteins; RNF126 is a Bag6-dependent E3 ubiquitin ligase that is involved in the mislocalized protein (MLP) pathway of quality control. It regulates the retrograde sorting of the cation-independent mannose 6-phosphate receptor (CI-MPR). Moreover, RNF126 promotes cancer cell proliferation by targeting the tumor suppressor p21 for ubiquitin-mediated degradation, and could be a novel therapeutic target in breast and prostate cancers. It is also able to ubiquitylate cytidine deaminase (AID), a poorly soluble protein that is essential for antibody diversification. In addition, RNF126 and the related protein, RNF115 associate with the epidermal growth factor receptor (EGFR) and promote ubiquitylation of EGFR, suggesting they play a role in the ubiquitin-dependent sorting and downregulation of membrane receptors. RNF126 contains an N-terminal BCA2 Zinc-finger domain (BZF), the AKT-phosphorylation sites, and the C-terminal C3H2C3-type RING-H2 finger.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*
gi 2462612425 127 CPICKEEFELRPQVL-LSCSHVFHKACLQAFekFTNKKTCPLCRK 170
Cdd:cd16801     2 CPVCKEDYTVGENVRqLPCNHLFHNDCIVPW--LEQHDTCPVCRK 44

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 2462612425 127 CPICKEEFelRPQVLLSCSHVFHKACLQAF-EKFTNKKTCPLCRK 170
Cdd:cd16611     7 CPLCLDFF--RDPVMLSCGHNFCQSCITGFwELQAEDTTCPECRE 49

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 2462612425 127 CPICKEEFE--LRPQVLLSCSHVFHKACLQAFEKfTNKKTCPLCR 169
Cdd:cd23121     4 CAICLSDFNsdEKLRQLPKCGHIFHHHCLDRWIR-YNKITCPLCR 47

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

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*
gi 2462612425 127 CPICKEEFElRPQVLLSCSHVFHKACLQAFEKFTNKKtCPLCRKN 171
Cdd:cd16544     5 CPVCQEVLK-DPVELPPCRHIFCKACILLALRSSGAR-CPLCRGP 47

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 2462612425 125 QPCPICKEEFElRPqVLLSCSHVFHKACLQAFekFTNKKTCPLCR 169
Cdd:cd16561     3 QECSICLEDLN-DP-VKLPCDHVFCEECIRQW--LPGQMSCPLCR 43

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

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|...
gi 2462612425 127 CPICKEEFELRPQV-LLSCSHVFHKACLQAFekFTNKKTCPLC 168
Cdd:cd16468     2 CVICMADFVVGDPIrYLPCMHIYHVDCIDDW--LMRSFTCPSC 42

zinc-RING finger domain;

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*
gi 2462612425 127 CPICKEEFEL-RPQVLLSCSHVFHKACLQafeKFTNKKTCPLCRK 170
Cdd:pfam14634   2 CNKCFKELSKtRPFYLTSCGHIFCEECLT---RLLQERQCPICKK 43

RING finger, H2 subclass, found in Saccharomyces cerevisiae alcohol-sensitive RING finger protein 1 (ASR1) and similar proteins; ASR1 is required for tolerance to alcohol. It signals alcohol stress to the nucleus. ASR1 contains a C3H2C3-type RING-H2 finger.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|...
gi 2462612425 127 CPICKEEFELRPQVLLSCSHVFHKACLQAFEKFTNKKTCPLCR 169
Cdd:cd23120     4 CPICLEEMNSGTGYLADCGHEFHLTCIREWHNKSGNLDCPICR 46

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 2462612425 127 CPICKEEFEL-RPQVLLSCSHVFHKACLqaFEKFTNKKTCPLCRK 170
Cdd:cd23116     5 CPTCLEGYTEeNPKLLTKCGHHFHLACI--YEWMERSERCPVCDK 47

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 2462612425 127 CPICKEEFELRPQV-LLSCSHVFHKACLQAFEKFTnKKTCPLCRK 170
Cdd:cd16797     3 CAICLDEYEEGDKLrVLPCSHAYHSKCVDPWLTQT-KKTCPVCKQ 46

RING finger, H2 subclass, found in Saccharomyces cerevisiae transmembrane E3 ubiquitin-protein ligase 1 (TUL1) and similar proteins; This subfamily includes Saccharomyces cerevisiae TUL1, Schizosaccharomyces pombe DSC E3 ubiquitin ligase complex subunit 1 (DSC1), and Arabidopsis thaliana protein FLYING SAUCER 2 (FLY2). TUL1 is the catalytic component of DSC E3 ubiquitin ligase complexes that tag proteins present in Golgi, endosome and vacuole membranes and function in protein homeostasis under non-stress conditions, and support a role in protein quality control. It mediates ubiquitination of vacuolar proteins such as CPS1, PPN1, PEP12 and other proteins containing exposed hydrophilic residues within their transmembrane domains, leading to their sorting into internal vesicles in late endosomes. TUL1 also targets the unpalmitoylated endosomal SNARE TLG1 to the multivesicular body (MVB) pathway. DSC1, also known as defective for SREBP cleavage protein 1, is the catalytic component of the DSC E3 ubiquitin ligase complex required for the sre1 transcriptional activator proteolytic cleavage to release the soluble transcription factor from the membrane in low oxygen or sterol conditions. FLY2 acts as an E3 ubiquitin-protein ligase that may be involved in xylem development. Members of this subfamily contain a C3H2C3-type RING-H2 finger.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|.
gi 2462612425 127 CPICKEEFELRPQVLLS-------CSHVFHKACLQAFEKFtnKKTCPLCRK 170
Cdd:cd23117     7 CVICMSDIELPSTNSVRrdymvtpCNHIFHTNCLERWMDI--KLECPTCRR 55

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

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 2462612425 109 EWEKVKQRSLLQGDSVQPCPICKEEFELRpqVLLSCSHVFHKACLQAFekFTNKKTCPLCRKNQYQTR 176
Cdd:COG5432    10 DWNQTKIPSLKGLDSMLRCRICDCRISIP--CETTCGHTFCSLCIRRH--LGTQPFCPVCREDPCESR 73

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

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|..
gi 2462612425 127 CPICKEEFElRPQVLLSCSHVFHKACLQAFEKfTNKKTCPLC 168
Cdd:pfam00097   1 CPICLEEPK-DPVTLLPCGHLFCSKCIRSWLE-SGNVTCPLC 40

RING finger, H2 subclass, found in RING finger proteins RNF139, RNF145, 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. RNF145 is an uncharacterized RING finger protein encoded by the RNF145 gene, which is expressed in T lymphocytes, and its expression is altered in acute myelomonocytic and acute promyelocytic leukemias. Although its biological function remains unclear, RNF145 shows high sequence similarity with RNF139. Both RNF139 and RNF145 contain a C3H2C3-type RING-H2 finger with possible E3-ubiquitin ligase activity.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|..
gi 2462612425 127 CPICKEEFelRPQVLLSCSHVFHKACLQAFekFTNKKTCPLC 168
Cdd:cd16476     3 CAICYQEM--KEARITPCNHFFHGLCLRKW--LYVQDTCPLC 40

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

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 2462612425 127 CPICKEEFelRPQVLLSCSHVFHKACLQAFEKftNKKTCPLCRKN-QYQTRVI 178
Cdd:cd16535     4 CSICSELF--IEAVTLNCSHSFCSYCITEWMK--RKKECPICRKPiTSKTRSL 52

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

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|...
gi 2462612425 127 CPICKEEFelRPQVLLSCSHVFHKACLQAFEKFTNKKTCPLCR 169
Cdd:cd16599     7 CPICYEPF--REAVTLRCGHNFCKGCVSRSWERQPRAPCPVCK 47

RING finger, H2 subclass, found in RING finger proteins RNF24, RNF122, and similar proteins; This subfamily includes RNF24, RNF122, 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. RNF122 is a RING finger protein associated with HEK 293T cell viability. It is localized to the endoplasmic reticulum (ER) and the Golgi apparatus, and overexpressed in anaplastic thyroid cancer cells. RNF122 functions as an E3 ubiquitin ligase that can ubiquitinate itself and undergo degradation through its RING finger in a proteasome-dependent manner. Both RNF24 and RNF122 contain an N-terminal transmembrane domain and a C-terminal C3H2C3-type RING-H2 finger.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*
gi 2462612425 127 CPICKEEFELRPQV-LLSCSHVFHKACLQAFEKFtnKKTCPLCRK 170
Cdd:cd16469     3 CAVCLEEFKLKEELgVCPCGHAFHTKCLKKWLEV--RNSCPICKS 45

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        30        40
                  ....*....|....*....|....*....|....*....|....
gi 2462612425 127 CPICkeeFELRPQVLLSCSHVFhkaCLQAFEKFT-NKKTCPLCR 169
Cdd:cd16545     3 CCIC---MDRKADLILPCAHSY---CQKCIDKWSdRHRTCPICR 40

RING finger, H2 subclass, found in RING finger proteins RNF111, RNF165, and similar proteins; The family includes RING finger proteins RNF111, RNF165, and similar proteins. RNF111, also known as Arkadia, is a nuclear E3 ubiquitin-protein ligase that targets intracellular effectors and modulators of transforming growth factor beta (TGF-beta)/Nodal-related signaling for polyubiquitination and proteasome-dependent degradation. It also interacts with the clathrin-adaptor 2 (AP2) complex and regulates endocytosis of certain cell surface receptors, leading to modulation of epidermal growth factor (EGF) and possibly other signaling pathways. The N-terminal half of RNF111 harbors three SUMO-interacting motifs (SIMs). It thus functions as a SUMO-targeted ubiquitin ligase (STUbL) that directly links nonproteolytic ubiquitylation and SUMOylation in the DNA damage response, as well as triggers degradation of signal-induced polysumoylated proteins, such as the promyelocytic leukemia protein (PML). RNF165, also known as Arkadia-like 2, Arkadia2, or Ark2C, is an E3 ubiquitin ligase with homology to the C-terminal half of RNF111. It is expressed specifically in the nervous system, and can serve to amplify neuronal responses to specific signals. It acts as a positive regulator of bone morphogenetic protein (BMP)-Smad signaling that is involved in motor neuron (MN) axon elongation. Both RNF165 and RNF111 contain a C-terminal C3H2C3-type RING-H2 finger.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*.
gi 2462612425 125 QPCPICKEEFELRPQV-LLSCSHVFHKACLQafEKFTNKKTCPLCR 169
Cdd:cd16474     1 EKCTICLSDFEEGEDVrRLPCMHLFHQECVD--QWLSTNKRCPICR 44

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 2462612425 127 CPICKEEFELRPQVLLSCSHVFHKACLQAFEKFTNkkTCPLCR 169
Cdd:cd16574     4 CPICLDRFENEKAFLDGCFHAFCFTCILEWSKVKN--ECPLCK 44

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 2462612425 120 QGDSVQPCPICKEEFELRPQV-LLSCSHVFHKACLQAFEKFTnKKTCPLCRK 170
Cdd:cd16796     4 KGDEYDVCAICLDEYEEGDKLrILPCSHAYHCKCVDPWLTKT-KKTCPVCKQ 54

RING finger, HC subclass, found in helicase-like transcription factor (HLTF) and similar proteins; HLTF, also known as DNA-binding protein/plasminogen activator inhibitor 1 regulator, HIP116, RING finger protein 80, SWI/SNF-related matrix-associated actin-dependent regulator of chromatin subfamily A member 3, or sucrose nonfermenting protein 2-like 3, is a yeast RAD5 homolog found in mammals. It has both E3 ubiquitin ligase and DNA helicase activities, and plays a pivotal role in the template-switching pathway of DNA damage tolerance. It is involved in Lys-63-linked poly-ubiquitination of proliferating cell nuclear antigen (PCNA) at Lys-164 and in the regulation of DNA damage tolerance. It shows double-stranded DNA translocase activity with 3'-5' polarity, thereby facilitating regression of the replication fork. HLTF contains an N-terminal HIRAN (HIP116 and RAD5 N-terminal) domain, a SWI/SNF helicase domain that is divided into N- and C-terminal parts by an insertion of a C3HC4-type RING-HC finger involved in the poly-ubiquitination of PCNA.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....
gi 2462612425 127 CPICKEEfeLRPQVLLSCSHVFHKACL-QAFEkfTNKKTCPLCR 169
Cdd:cd16509     6 CAICLDS--LTNPVITPCAHVFCRRCIcEVIQ--REKAKCPMCR 45

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 2462612425 127 CPICKEEFELRPQVLlSCSHVFHKACLQAFEKFTNKKTCPLCR 169
Cdd:cd16749     3 CPVCFEKLDVTAKVL-PCQHTFCKPCLQRIFKARKELRCPECR 44

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

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|...
gi 2462612425 127 CPICKEEFElRPQVLLSCSHVFHKACLQAfeKFTNKKTCPLCR 169
Cdd:cd16506     3 CPICLDEIQ-NKKTLEKCKHSFCEDCIDR--ALQVKPVCPVCG 42

RING finger, HC subclass, found in Saccharomyces cerevisiae translation termination inhibitor protein ITT1 and similar proteins; ITT1 is a protein that modulates the efficiency of translation termination, resulting in the readthrough of all three types of nonsense codons UAA, UAG and UGA. ITT1 contains a typical C3HC4-type RING-HC finger.

                          10        20        30
                  ....*....|....*....|....*....|....
gi 2462612425 123 SVQPCPICKEEFELRPQVLLSCSHVFHKACLQAF 156
Cdd:cd23134     3 SSYHCGICFEEKKGSDFIKLPCGHVFCRECLQDY 36

RING-CH finger, H2 subclass (C4HC3-type), found in E3 ubiquitin-protein ligase listerin and similar proteins; Listerin, also known as RING finger protein 160 or zinc finger protein 294, is the mammalian homolog of yeast Ltn1. It is widely expressed in all tissues, but motor and sensory neurons and neuronal processes in the brainstem and spinal cord are primarily affected in the mutant. Listerin is required for embryonic development and plays an important role in neurodegeneration. It also functions as a critical E3 ligase involving quality control of nonstop proteins. It mediates ubiquitylation of aberrant proteins that become stalled on ribosomes during translation. Ltn1 works with several cofactors to form a large ribosomal subunit-associated quality control complex (RQC), which mediates the ubiquitylation and extraction of ribosome-stalled nascent polypeptide chains for proteasomal degradation. It appears to first associate with nascent chain-stalled 60S subunits together with two proteins of unknown function, Tae2 and Rqc1. Listerin contains a long stretch of HEAT (Huntingtin, Elongation factor 3, PR65/A subunit of protein phosphatase 2A, and TOR) or ARM (Armadillo) repeats in the N terminus and middle region, and a catalytic RING-CH finger, also known as vRING or RINGv, with an unusual arrangement of zinc-coordinating residues in the C-terminus . Its cysteines and histidines are arranged in the sequence as C4HC3-type, rather than the C3H2C3-type in canonical RING-H2 finger.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*....
gi 2462612425 126 PCPIC-----KEEFELRPQVLLSCSHVFHKACLQAFEKFTNKKTCPLCR 169
Cdd:cd16491     2 ECPICysvihGSNHSLPKLKCKTCKNKFHSACLYKWFRSSNKSTCPLCR 50

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 2462612425 127 CPICKEEFELRPQV-LLSCSHVFHKACLQAFekFTNKKTCPLCRKN 171
Cdd:cd16668     2 CAVCIEPYKPSDVIrILPCKHIFHKSCVDPW--LLEHRTCPMCKLD 45

RING-like zinc finger;

                          10        20
                  ....*....|....*....|....*...
gi 2462612425 127 CPICKEEFEL-RPQVLLSCSHVFHKACL 153
Cdd:pfam17123   2 CSICLDEFKPgQALFVLPCSHVFHYKCI 29

RING finger, HC subclass, found in tripartite motif-containing protein 32 (TRIM32) and similar proteins; TRIM32, also known as 72 kDa Tat-interacting protein, zinc finger protein HT2A, or BBS11, is an E3 ubiquitin-protein ligase that promotes degradation of several targets, including actin, PIASgamma, Abl interactor 2, dysbindin, X-linked inhibitor of apoptosis (XIAP), p73 transcription factor, thin filaments and Z-bands during fasting. It plays important roles in neuronal differentiation of neural progenitor cells, as well as in controlling cell fate in skeletal muscle progenitor cells. It reduces PI3K-Akt-FoxO signaling in muscle atrophy by promoting plakoglobin-PI3K dissociation. It also functions as a pluripotency-reprogramming roadblock that facilitates cellular transition towards differentiation by modulating the levels of Oct4 and cMyc. Moreover, TRIM32 is an intrinsic influenza A virus (IAV) restriction factor which senses and targets the polymerase basic protein 1 (PB1) for ubiquitination and protein degradation. It also plays a significant role in mediating the biological activity of the HIV-1 Tat protein in vivo, binds specifically to the activation domain of HIV-1 Tat, and can also interact with the HIV-2 and EIAV Tat proteins in vivo. Furthermore, TRIM32 regulates myoblast proliferation by controlling turnover of NDRG2 (N-myc downstream-regulated gene). It negatively regulates tumor suppressor p53 to promote tumorigenesis. It also facilitates degradation of MYCN on spindle poles and induces asymmetric cell division in human neuroblastoma cells. In addition, TRIM32 plays important roles in regulation of hyperactivities and positively regulates the development of anxiety and depression disorders induced by chronic stress. It also plays a role in regeneration by affecting satellite cell cycle progression via modulation of the SUMO ligase PIASy (PIAS4). Defects in TRIM32 leads to limb-girdle muscular dystrophy type 2H (LGMD2H), sarcotubular myopathies (STM) and Bardet-Biedl syndrome. TRIM32 belongs to the C-VII subclass of the TRIM (tripartite motif)-NHL family that is defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil domain, as well as a NHL (named after proteins NCL-1, HT2A and Lin-41 that contain repeats folded into a six-bladed beta propeller) repeat domain positioned C-terminal to the RBCC domain. The NHL domain mediates the interaction with Argonaute proteins and consequently allows TRIM32 to modulate the activity of certain miRNAs.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 2462612425 127 CPICKEEF---ELRPQVLlscsHVFHKACLQAFEKFTNKKT-----CPLCRKN 171
Cdd:cd16587     3 CPICLESFdegQLRPKLL----HCGHTICEQCLEKLLASLSingvrCPFCRKV 51

RING-CH finger, H2 subclass (C4HC3-type), found in zinc finger SWIM domain-containing protein 2 (ZSWIM2) and similar proteins; ZSWIM2, also known as MEKK1-related protein X (MEX) or ZZ-type zinc finger-containing protein 2, is a testis-specific E3 ubiquitin ligase that promotes death receptor-induced apoptosis through Fas, death receptor (DR) 3, and DR4 signaling. ZSWIM2 is self-ubiquitinated and targeted for degradation through the proteasome pathway. It also acts as an E3 ubiquitin ligase, through the E2, Ub-conjugating enzymes UbcH5a, UbcH5c, or UbcH6. ZSWIM2 contains four putative zinc-binding domains including an N-terminal SWIM (SWI2/SNF2 and MuDR) domain critical for its ubiquitination and two RING fingers separated by a ZZ zinc finger domain, which was required for interaction with UbcH5a and its self-association. This model corresponds to the first RING finger, which is a C4HC3-type RING-CH finger, also known as vRING or RINGv, rather than the canonical C3H2C3-type RING-H2 finger.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|.
gi 2462612425 127 CPICKEEFELRPQVLL----SCSHVFHKACLQAFEKF----TNKKTCPLCR 169
Cdd:cd16494     4 CPICYEEMLEKGEPLTycrfGCGNNVHIHCMKVWAEHqrqsDEPVTCPLCR 54

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
                  ....*....|....*....|....*....|....*....|....*..
gi 2462612425 127 CPICKEEFELRPQ---VLLSCSHVFHKACLQAFEKfTNKKTCPLCRK 170
Cdd:cd16450     5 CPICFEPWTSSGEhrlVSLKCGHLFGYSCIEKWLK-GKGKKCPQCNK 50

RING finger, H2 subclass, found in RING finger protein 44 (RNF44) and similar proteins; RNF44 is an uncharacterized RING finger protein that shows high sequence similarity with RNF38, which is a nuclear E3 ubiquitin protein ligase that plays a role in regulating p53. RNF44 contains a coiled-coil motif, a KIL motif (Lys-X2-Ile/Leu-X2-Ile/Leu, X can be any amino acid), and a C3H2C2-type RING-H2 finger.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*.
gi 2462612425 127 CPICKEEFELRPQV-LLSCSHVFHKACLQAFEKftNKKTCPLCRKN 171
Cdd:cd16680    10 CVVCFSDFESRQLLrVLPCNHEFHTKCVDKWLK--TNRTCPICRAD 53

RING finger, H2 subclass, found in E3 ubiquitin-protein ligase Deltex1 (DTX1), Deltex2 (DTX2), Deltex4 (DTX4), and similar proteins; This subfamily contains the vertebrate homologs of Drosophila melanogaster Deltex, specifically DTX1, DTX2, and DTX4, and other similar proteins mainly from eumetazoa. The vertebrate homologs of Deltex are involved in Notch signaling and neurogenesis. Mammalian DTX1 is most closely related to the Drosophila Deltex. Both of them bind to SH3-domain containing protein Grb2 and further inhibit E2A. DTX1 functions as a Notch downstream transcription regulator. It interacts with the transcription coactivator p300 and inhibits transcription activation mediated by the neural specific transcription factor MASH1. It is also a transcription target of nuclear factor of activated T cells (NFAT) and participates in T cell anergy and Foxp3 protein level maintenance in vivo. Moreover, DTX1 promotes protein kinase C theta degradation and sustains Casitas B-lineage lymphoma expression. DTX4, also known as RING finger protein 155, shares the highest degree of sequence similarity with DTX1. So it likely interacts with the intracellular domain of Notch as well. Like DTX1 and DTX4, DTX2 is expressed in thymocytes. It interacts with the intracellular domain of Notch receptors and acts as a negative regulator of Notch signals in T cells. However, the endogenous levels of DTX1 and DTX2 is not important for regulating Notch signals during thymocyte development. In contrast to other DTXs, DTX3 does not contain two Notch-binding WWE domains at the N-terminus, but rather a short unique N-terminal domain. It does not interact with the intracellular domain of Notch. In addition, it has a different class of RING finger (C3HC4 type or RING-HC subclass), compared with the other DTXs which harbor a C3H2C3-type RING-H2 finger. Thus DTX3 is not included in this subfamily. Drosophila melanogaster Deltex also does not belong to this subfamily.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*....
gi 2462612425 127 CPICKEEFE----------LRPQV---LLSCSHVFHKACLQAFEKFTNKK---TCPLCR 169
Cdd:cd16459     2 CPICCEPLCvasgyeesklEGSKVvvrLKKCSHMYHKACLVAMYSNGAKDgslQCPTCK 60

RING finger, H2 subclass, found in RING finger protein 149 (RNF149) and similar proteins; RNF149, also known as DNA polymerase-transactivated protein 2, is an E3 ubiquitin-protein ligase that interacts with wild-type v-Raf murine sarcoma viral oncogene homolog B1 (BRAF), a RING domain-containing E3 ubiquitin ligase involved in control of gene transcription, translation, cytoskeletal organization, cell adhesion, and epithelial development. RNF149 induces the ubiquitination of wild-type BRAF and promotes its proteasome-dependent degradation. Mutated RNF149 has been found in some human breast, ovarian, and colorectal cancers. RNF149 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 2462612425 127 CPICKEEFELRPQV-LLSCSHVFHKACLQAFekFTNKKTCPLCR 169
Cdd:cd16804     2 CAVCIENYKSKDVVrILPCKHVFHRICIDPW--LLEHRTCPMCK 43

RING finger, H2 subclass, found in vacuolar protein sorting-associated protein 11 homolog (Vps11) and similar proteins; Vps11, also known as RING finger protein 108 (RNF108), is a soluble protein involved in regulation of glycolipid degradation and retrograde toxin transport. It is highly expressed in heart and pancreas. Vps11 associates with Vps16, Vps18, and Vps33 to form a Class C Vps core complex that is required for soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNARE)-mediated membrane fusion at the lysosome-like yeast vacuole. The core complex, together with two additional compartment-specific subunits, forms the tethering complexes HOPS (homotypic vacuole fusion and protein sorting) and CORVET (class C core vacuole/endosome transport). CORVET contains the additional Vps3 and Vps8 subunits. It operates at endosomes, controls traffic into late endosomes and interacts with the Rab5/Vps21-GTP form. HOPS contains the additional Vps39 and Vps41 subunits. It operates at the lysosomal vacuole, controls all traffic from late endosomes into the vacuole and interacts with the Rab7/Ypt7-GTP form. Vps11 is a central scaffold protein upon which both HOPS and CORVET assemble. The HOPS and CORVET complexes disassemble in the absence of Vps11, resulting in massive fragmentation of vacuoles. Vps11 contains a clathrin repeat domain and a C-terminal C3H2C3-type RING-H2 finger. This subfamily also includes Vps11 homologs found in fungi, such as Saccharomyces cerevisiae vacuolar membrane protein Pep5p, also known as carboxypeptidase Y-deficient protein 5, vacuolar morphogenesis protein 1, or vacuolar biogenesis protein END1. Pep5p is essential for vacuolar biogenesis. It associates with Pep3p to form a core Pep3p/Pep5p complex that promotes vesicular docking/fusion reactions in conjunction with SNARE proteins at multiple steps in transport routes to the vacuole.

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                  ....*....|....*....|....*....|....*....|...
gi 2462612425 127 CPICKEEFELrPQVLLSCSHVFHKACLQafEKFTNKKTCPLCR 169
Cdd:cd16688     3 CSACGSTLDL-PSVHFLCGHSFHQHCLE--DYEENDRECPLCA 42

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

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*..
gi 2462612425 127 CPICKEEfeLRPQVLLSCSHVFHKACL-QAFEKFTNKK--TCPLCRK 170
Cdd:cd16583     8 CPICQEP--LKEAVSTDCGHLFCRMCLtQHAKKASASGvfSCPVCRK 52