RING finger (Really Interesting New Gene) domain and U-box domain superfamily; The RING finger is a specialized type of Zn-finger of 40 to 60 residues that binds two atoms of zinc. It is defined by the "cross-brace" motif that chelates zinc atoms by eight amino acid residues, typically Cys or His, arranged in a characteristic spacing. Canonical RING motifs have been categorized into two major subclasses, RING-HC (C3HC4-type) and RING-H2 (C3H2C3-type), according to their Cys/His content. There are also many variants of RING fingers: some have different Cys/His patterns while some lack a single Cys or His residue at typical Zn ligand positions (the fourth or eighth zinc ligand is prevalently exchanged for an Asp, which can indeed chelate Zn in a RING finger as well). C4C4-, C3HC3D-, C2H2C4-, and C3HC5-type RING fingers are closely related to RING-HC fingers. In contrast, C4HC3- (RING-CH alias RINGv), C3H3C2-, C3H2C2D-, C3DHC3-, and C4HC2H-type RING fingers are more closely related to RING-H2 fingers. However, not all RING finger-containing proteins display regular RING finger features, and the RING finger family has turned out to be multifarious. The degenerate RING fingers of the Siz/PIAS RING (SP-RING) family proteins and sporulation protein RMD5, are characterized by lacking the second, fifth, and sixth Zn2+ ion-coordinating residues. They bind only one Zn2+ ion. On the other hand, the RING fingers of the human APC11 and RBX1 proteins can bind a third Zn atom since they harbor four additional Zn ligands. U-box is a modified form of the RING finger domain that lacks metal chelating Cys and His residues. It resembles the cross-brace RING structure consisting of three beta-sheets and a single alpha-helix, which would be stabilized by salt bridges instead of chelated metal ions. U-box proteins are widely distributed among eukaryotic organisms and show a higher prevalence in plants than in other organisms. RING finger/U-box-containing proteins are a group of diverse proteins with a variety of cellular functions, including oncogenesis, development, viral replication, signal transduction, the cell cycle and apoptosis. Many of them are ubiquitin-protein ligases (E3s) that serve as scaffolds for binding to ubiquitin-conjugating enzymes (E2s, also referred to as ubiquitin carrier proteins or UBCs) in close proximity to substrate proteins, which enable efficient transfer of ubiquitin from E2 to the substrates.

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gi 1754388283   1 ASNPLWQSRSSTTVSSGGRFRCPSCR 26
Cdd:cd16761    34 ASNPLWQSRGSSTVSSGGRFRCPSCR 59

RING finger, HC subclass, found in muscle-specific RING finger protein 3 (MuRF-3) and similar proteins; MuRF-3, also known as tripartite motif-containing protein 54 (TRIM54), or RING finger protein 30 (RNF30), is an E3 ubiquitin-protein ligase in ubiquitin-mediated muscle protein turnover. It is ubiquitously detected in all fibre types, is developmentally upregulated, associates with microtubules, the sarcomeric M-line and Z-line, and is required for microtubule stability and myogenesis. It associates with glutamylated microtubules during skeletal muscle development, and is required for skeletal myoblast differentiation and development of cellular microtubular networks. MuRF-3 controls the degradation of four-and-a-half LIM domain (FHL2) and gamma-filamin and is required for maintenance of ventricular integrity after myocardial infarction (MI). MuRF-3 belongs to the C-II subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox2, and a coiled coil region, as well as a COS (carboxyl-terminal subgroup one signature) box, and an acidic residue-rich (AR) domain. It also harbors a MURF family-specific conserved box (MFC) between its RING-HC finger and Bbox domains.

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gi 1754388283   1 ASNPLWQSRSSTTVSSGGRFRCPSCR 26
Cdd:cd16761    34 ASNPLWQSRGSSTVSSGGRFRCPSCR 59

B-Box-type zinc finger;

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gi 1754388283   68 LMCEEHEDEKINIYCLSCEVPTCSLCKVFgAHKDCEVAPL 107
Cdd:smart00336   4 PKCDSHGDEPAEFFCEECGALLCRTCDEA-EHRGHTVVLL 42

B-box-type 2 zinc finger found in muscle-specific RING finger protein 1 (MuRF-1) and similar proteins; MuRF-1, also known as tripartite motif-containing protein 63 (TRIM63), RING finger protein 28 (RNF28), iris RING finger protein, or striated muscle RING zinc finger, is an E3 ubiquitin-protein ligase in ubiquitin-mediated muscle protein turnover. It is predominantly fast (type II) fibre-associated in skeletal muscle and can bind to many myofibrillar proteins, including titin, nebulin, the nebulin-related protein NRAP, troponin-I (TnI), troponin-T (TnT), myosin light chain 2 (MLC-2), myotilin, and T-cap. The early and robust upregulation of MuRF-1 is triggered by disuse, denervation, starvation, sepsis, or steroid administration resulting in skeletal muscle atrophy. It also plays a role in maintaining titin M-line integrity. It associates with the periphery of the M-line lattice and may be involved in the regulation of the titin kinase domain. It also participates in muscle stress response pathways and gene expression. MuRF-1 belongs to the C-II subclass of TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a RING finger, Bbox2, and a coiled coil region, as well as a COS (carboxyl-terminal subgroup one signature) box, and an acidic residue-rich (AR) domain. It also harbors a MURF family-specific conserved box (MFC) between its RING-HC finger and Bbox domains. The type 2 B-box (Bbox2) zinc finger is characterized by a CHC3H2 zinc-binding consensus motif.

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gi 1754388283  67 HLMCEEHEDEKINIYCLSCEVPTCSLCKVFGAHKDCEVAPLP 108
Cdd:cd19831     2 HPMCKEHEDEKINIYCLTCEVPTCSMCKVFGIHKACEVAPLQ 43

B-box-type 2 zinc finger found in muscle-specific RING finger protein (MuRF) family; This family corresponds to a group of striated muscle-specific tripartite motif (TRIM) proteins, including TRIM63/MuRF-1, TRIM55/MuRF-2, and TRIM54/MuRF-3, which function as E3 ubiquitin ligases in ubiquitin-mediated muscle protein turnover. They are tightly developmentally regulated in skeletal muscle and associate with different cytoskeleton components, such as microtubules, Z-disks and M-bands, as well as with metabolic enzymes and nuclear proteins. They also cooperate with diverse proteins implicated in selective protein degradation by the proteasome and autophagosome, and target proteins of metabolic regulation, sarcomere assembly and transcriptional regulation. Moreover, MURFs display variable fibre-type preferences. TRIM63/MuRF-1 is predominantly fast (type II) fibre-associated in skeletal muscle. TRIM55/MuRF-2 is predominantly slow-fibre associated. TRIM54/MuRF-3 is ubiquitously present. They play an active role in microtubule-mediated sarcomere assembly. MuRFs belong to the C-II subclass of TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a RING finger, Bbox2, and a coiled coil region, as well as a COS (carboxyl-terminal subgroup one signature) box, and an acidic residue-rich (AR) domain positioned C-terminal to the RBCC domain. They also harbor a MURF family-specific conserved box (MFC) between its RING-HC finger and Bbox domains. The type 2 B-box (Bbox2) zinc finger is characterized by a CHC3H2 zinc-binding consensus motif.

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gi 1754388283  69 MCEEHEDEKINIYCLSCEVPTCSLCKVFGAHKDCEVAPL 107
Cdd:cd19788     1 MCEEHEEEKINIYCLTCEVPTCSMCKVFGAHKDCEVAPL 39

RING finger, HC subclass, found in muscle-specific RING finger protein 3 (MuRF-3) and similar proteins; MuRF-3, also known as tripartite motif-containing protein 54 (TRIM54), or RING finger protein 30 (RNF30), is an E3 ubiquitin-protein ligase in ubiquitin-mediated muscle protein turnover. It is ubiquitously detected in all fibre types, is developmentally upregulated, associates with microtubules, the sarcomeric M-line and Z-line, and is required for microtubule stability and myogenesis. It associates with glutamylated microtubules during skeletal muscle development, and is required for skeletal myoblast differentiation and development of cellular microtubular networks. MuRF-3 controls the degradation of four-and-a-half LIM domain (FHL2) and gamma-filamin and is required for maintenance of ventricular integrity after myocardial infarction (MI). MuRF-3 belongs to the C-II subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox2, and a coiled coil region, as well as a COS (carboxyl-terminal subgroup one signature) box, and an acidic residue-rich (AR) domain. It also harbors a MURF family-specific conserved box (MFC) between its RING-HC finger and Bbox domains.

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gi 1754388283   1 ASNPLWQSRSSTTVSSGGRFRCPSCR 26
Cdd:cd16761    34 ASNPLWQSRGSSTVSSGGRFRCPSCR 59

B-box-type 2 zinc finger found in tripartite motif-containing protein 36 (TRIM36) and similar proteins; TRIM36, human ortholog of mouse Haprin, also known as RING finger protein 98 (RNF98) or zinc-binding protein Rbcc728, is an E3 ubiquitin-protein ligase expressed in the germ plasm. It has been implicated in acrosome reaction, fertilization, and embryogenesis, as well as in carcinogenesis. TRIM36 functions upstream of Wnt/beta-catenin activation, and plays a role in controlling the stability of proteins regulating microtubule polymerization during cortical rotation, and subsequently dorsal axis formation. It is also potentially associated with chromosome segregation through interacting with the kinetochore protein centromere protein-H (CENP-H), and colocalizing with the microtubule protein alpha-tubulin. Its overexpression may cause chromosomal instability and carcinogenesis. It is, thus, a novel regulator affecting cell cycle progression. Moreover, TRIM36 plays a critical role in the arrangement of somites during embryogenesis. TRIM36 belongs to the C-I subclass of TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a RING finger, Bbox1 and Bbox2, and a coiled coil region, as well as a COS (carboxyl-terminal subgroup one signature) box, a fibronectin type III (FN3) domain, and a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain. The type 2 B-box (Bbox2) zinc finger is characterized by a CHC3H2 zinc-binding consensus motif.

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gi 1754388283  68 LMCEEHEDEKINIYCLSCEVPTCSLCKVFGAHKDCEVAPLPTIYK 112
Cdd:cd19778     1 LMCPEHEMEKVNMYCEACRRPVCHLCKLGGSHANHRVTSMSSAYK 45

RING finger, HC subclass, found in muscle-specific RING finger protein 1 (MuRF-1) and similar proteins; MuRF-1, also known as tripartite motif-containing protein 63 (TRIM63), RING finger protein 28 (RNF28), iris RING finger protein, or striated muscle RING zinc finger, is an E3 ubiquitin-protein ligase in ubiquitin-mediated muscle protein turnover. It is predominantly fast (type II) fibre-associated in skeletal muscle and can bind to many myofibrillar proteins, including titin, nebulin, the nebulin-related protein NRAP, troponin-I (TnI), troponin-T (TnT), myosin light chain 2 (MLC-2), myotilin, and T-cap. The early and robust upregulation of MuRF-1 is triggered by disuse, denervation, starvation, sepsis, or steroid administration resulting in skeletal muscle atrophy. It also plays a role in maintaining titin M-line integrity. It associates with the periphery of the M-line lattice and may be involved in the regulation of the titin kinase domain. It also participates in muscle stress response pathways and gene expression. MuRF-1 belongs to the C-II subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox2, and a coiled coil region, as well as a COS (carboxyl-terminal subgroup one signature) box, and an acidic residue-rich (AR) domain. It also harbors a MURF family-specific conserved box (MFC) between its RING-HC finger and Bbox domains.

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gi 1754388283   1 ASNPLWQSRSSTTVSSGGRFRCPSCRH 27
Cdd:cd16759    37 AANPYWQSRGTSMLGSGGRFRCPSCRH 63

RING finger, HC subclass, found in muscle-specific RING finger protein 2 (MuRF-2) and similar proteins; MuRF-2, also known as tripartite motif-containing protein 55 (TRIM55) or RING finger protein 29 (RNF29), is a muscle-specific E3 ubiquitin-protein ligase in ubiquitin-mediated muscle protein turnover and is also a ligand of the transactivation domain of the serum response transcription factor (SRF). It is predominantly slow-fibre associated and highly expressed in embryonic skeletal muscle. MuRF-2 associates transiently with microtubules, myosin, and titin during sarcomere assembly. It has been implicated in microtubule, intermediate filament, and sarcomeric M-line maintenance in striated muscle development, as well as in signaling from the sarcomere to the nucleus. It plays an important role in the earliest stages of skeletal muscle differentiation and myofibrillogenesis. It is developmentally downregulated and is assembled at the M-line region of the sarcomere and with microtubules. MuRF-2 belongs to the C-II subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox2, and a coiled coil region, as well as a COS (carboxyl-terminal subgroup one signature) box, and an acidic residue-rich (AR) domain. It also harbors a MURF family-specific conserved box (MFC) between its RING-HC finger and Bbox domains.

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gi 1754388283   1 ASNPLWQSRSSTTVSSGGRFRCPSCRHE 28
Cdd:cd16760    37 ASNPYLPTRGGTTVASGGRFRCPSCRHE 64

B-box-type 2 zinc finger found in tripartite motif-containing protein 67 (TRIM67) and similar proteins; TRIM67, also termed TRIM9-like protein (TNL), is a protein selectively expressed in the cerebellum. It interacts with PRG-1, an important molecule in the control of hippocampal excitability dependent on presynaptic LPA2 receptor signaling, and 80K-H (also known as glucosidase II beta), a protein kinase C substrate. It negatively regulates Ras signaling in cell proliferation via degradation of 80K-H, leading to neural differentiation including neuritogenesis. TRIM67 belongs to the C-I subclass of TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a RING finger, Bbox1 and Bbox2, and a coiled coil region, as well as a COS (carboxyl-terminal subgroup one signature) box, the fibronectin type III domain and the SPRY/B30.2 domain positioned C-terminal to the RBCC domain. The type 2 B-box (Bbox2) zinc finger is characterized by a CHC3H2 zinc-binding consensus motif.

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gi 1754388283  70 CEEHEDEKINIYCLSCEVPTCSLCKVFGAHKDCEVAPLPTIYK 112
Cdd:cd19827     3 CAEHELENYSMYCASCRTPVCYQCLEEGKHAKHEVKALGAMWK 45

B-box-type 2 zinc finger found in tripartite motif-containing proteins, TRIM9, TRIM67 and similar proteins; This family includes a group of tripartite motif-containing proteins including TRIM9 and TRIM67, both of which belong to the C-I subclass of TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, consisting of three consecutive zinc-binding domains, a RING finger, Bbox1 and Bbox2, and a coiled coil region, as well as a COS (carboxyl-terminal subgroup one signature) box, a fibronectin type III (FN3) domain, and a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain. The type 2 B-box (Bbox2) zinc finger is characterized by a CHC3H2 zinc-binding consensus motif. TRIM9 (the human ortholog of rat Spring), also known as RING finger protein 91 (RNF91), is a brain-specific E3 ubiquitin-protein ligase collaborating with an E2 ubiquitin conjugating enzyme UBCH5b. It plays an important role in the regulation of neuronal functions and participates in neurodegenerative disorders through its ligase activity. TRIM67, also termed TRIM9-like protein (TNL), is a protein selectively expressed in the cerebellum. It interacts with PRG-1, an important molecule in the control of hippocampal excitability dependent on presynaptic LPA2 receptor signaling, and 80K-H (also known as glucosidase II beta), a protein kinase C substrate. It negatively regulates Ras signaling in cell proliferation via degradation of 80K-H, leading to neural differentiation including neuritogenesis.

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gi 1754388283  69 MCEEHEDEKINIYCLSCEVPTCSLCKVFGAHKDCEVAPL 107
Cdd:cd19764     1 TCSEHPDEALSMYCLSCKVPVCYLCLEDGRHSNHDVQAL 39

B-Box-type zinc finger;

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gi 1754388283   68 LMCEEHEDEKINIYCLSCEVPTCSLCKVFgAHKDCEVAPL 107
Cdd:smart00336   4 PKCDSHGDEPAEFFCEECGALLCRTCDEA-EHRGHTVVLL 42

B-box-type 2 zinc finger found in tripartite motif-containing protein 9 (TRIM9) and similar proteins; TRIM9 (the human ortholog of rat Spring), also termed RING finger protein 91 (RNF91), is a brain-specific E3 ubiquitin-protein ligase collaborating with an E2 ubiquitin conjugating enzyme UBCH5b. TRIM9 plays an important role in the regulation of neuronal functions and participates in the neurodegenerative disorders through its ligase activity. It interacts with the WD repeat region of beta-transducer repeat-containing protein (beta-TCP) through its N-terminal degron motif (DSGXXS) depending on the phosphorylation status, and thus negatively regulate nuclear factor-kappaB (NF-kappaB) activation in the NF-kappaB pro-inflammatory signaling pathway. Moreover, TRIM9 acts as a critical catalytic link between Netrin-1 and exocytosis soluble NSF attachment receptor protein (SNARE) machinery in murine cortical neurons. It promotes SNARE-mediated vesicle fusion and axon branching in a Netrin-dependent manner. TRIM9 belongs to the C-I subclass of TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a RING finger, Bbox1 and Bbox2, and a coiled coil region, as well as a COS (carboxyl-terminal subgroup one signature) box, the fibronectin type III domain and the SPRY/B30.2 domain positioned C-terminal to the RBCC domain. The type 2 B-box (Bbox2) zinc finger is characterized by a CHC3H2 zinc-binding consensus motif.

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gi 1754388283  70 CEEHEDEKINIYCLSCEVPTCSLCKVFGAHKDCEVAPLPTIYK 112
Cdd:cd19826     7 CTDHELENHSMYCVQCKMPVCYQCLEEGKHSSHEVKALGAMWK 49

coiled-coil (CC) domain of Drosophila brain tumor (brat) and similar proteins; This family contains the coiled-coil (CC) region of Drosophila brain tumor (Brat), a translational repressor that belongs to the tripartite motif (TRIM) protein superfamily. TRIM proteins play important roles in various cellular processes and are involved in many diseases which consists of two B-box domains and a coiled-coil (CC) domain at the N-terminal region, and an NHL domain at the C-terminus. Brat localizes at the basal cortex during asymmetric division of Drosophila neuroblasts by directly interacting with the scaffolding protein Miranda (Mira), which it does through the CC-NHL domain tandem, indicating that the function of the Brat CC domain is to assemble Brat-NHL in dimeric form which is necessary for Mira binding. Brat CC forms an elongated antiparallel dimer similar to its other TRIM protein counterparts, but the overall length of Brat CC dimer is shorter than the TRIMs.

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gi 1754388283 132 VQAVITQMEEVCQTIEENSRRQKQLLNQRFEGLCAVLEERKGELLQALA---KEQEEKLQRVRGLIRQYGDHLEASSKLV 208
Cdd:cd20482    19 LRDALKNVEHALSRLQMQYHKAQNEINETFQFYRSMLEERKDELLKELEsiyNAKQLSLNEQQQKLQETIEKIQQGCEFT 98

                          90
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gi 1754388283 209 ESAIQSMEEPQMALYLQQ 226
Cdd:cd20482    99 ERLLKHGSETEVLLFKKL 116

B-box-type 2 zinc finger found in tripartite motif-containing protein 71 (TRIM71) and similar proteins; TRIM71, also known as protein lineage variant 41 (lin-41), is an E3 ubiquitin-protein ligase that may play essential roles in embryonic stem cells, cellular reprogramming, and the timing of embryonic neurogenesis. It was first identified in the nematode Caenorhabditis elegans as a target of the differentiation-associated microRNA (miRNA) let-7 (lethal 7), and therefore part of a heterochronic gene network that controls larval development. In humans, it regulates let-7 microRNA biogenesis via modulation of Lin28B protein polyubiquitination. TRIM71 localizes to cytoplasmic P-bodies and directly interacts with the miRNA pathway proteins Argonaute 2 (AGO2) and DICER. It represses miRNA activity by promoting degradative ubiquitination of AGO2. Moreover, TRIM71 associates with SHCBP1, a novel component of the fibroblast growth factor (FGF) signaling pathway, and regulates its non-degradative polyubiquitination. It is also involved in the post-transcriptional regulation of the CDKN1A, RBL1 and RBL2 or EGR1 mRNAs through mediating RNA-binding in embryonic stem cells. TRIM71 belongs to the C-VII subclass of 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 RING 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 type 2 B-box (Bbox2) zinc finger is characterized by a CHC3H2 zinc-binding consensus motif.

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gi 1754388283  70 CEEHEDEKINIYCLSCEVPTCSLC 93
Cdd:cd19796     4 CEIHEHEVLRLYCDTCSVPICREC 27