B-box-type 2 zinc finger found in tripartite motif-containing protein 14 (TRIM14) and similar proteins; TRIM14 is a mitochondrial adaptor that facilitates innate immune signaling. It also plays a critical role in tumor development. TRIM14 belongs to an unclassified TRIM (tripartite motif) family of proteins that do not have RING fingers and thus lack the characteristic tripartite (RING (R), B-box, and coiled coil (CC)) RBCC motif. It contains a Bbox2 zinc finger as well as a C-terminal SPRY/B30.2 domain. The type 2 B-box (Bbox2) zinc finger is characterized by a CHC3H2 zinc-binding consensus motif.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....
gi 1039768890  20 WRCPEHSERPAELFCRRCGRCVCALCPVLGAHRGHPVGLAEEEA 63
Cdd:cd19768     1 RCCPEHKDRPLELFCKTCKRCVCALCPILGQHRGHDVRLIDEEA 44

B-box-type 2 zinc finger found in tripartite motif-containing protein 14 (TRIM14) and similar proteins; TRIM14 is a mitochondrial adaptor that facilitates innate immune signaling. It also plays a critical role in tumor development. TRIM14 belongs to an unclassified TRIM (tripartite motif) family of proteins that do not have RING fingers and thus lack the characteristic tripartite (RING (R), B-box, and coiled coil (CC)) RBCC motif. It contains a Bbox2 zinc finger as well as a C-terminal SPRY/B30.2 domain. The type 2 B-box (Bbox2) zinc finger is characterized by a CHC3H2 zinc-binding consensus motif.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....
gi 1039768890  20 WRCPEHSERPAELFCRRCGRCVCALCPVLGAHRGHPVGLAEEEA 63
Cdd:cd19768     1 RCCPEHKDRPLELFCKTCKRCVCALCPILGQHRGHDVRLIDEEA 44

B-Box-type zinc finger;

                           10        20        30
                   ....*....|....*....|....*....|....*....
gi 1039768890   20 WRCPEHSERPAELFCRRCGRCVCALCpVLGAHRGHPVGL 58
Cdd:smart00336   4 PKCDSHGDEPAEFFCEECGALLCRTC-DEAEHRGHTVVL 41

B-box-type 2 zinc finger found in tripartite motif-containing protein 14 (TRIM14) and similar proteins; TRIM14 is a mitochondrial adaptor that facilitates innate immune signaling. It also plays a critical role in tumor development. TRIM14 belongs to an unclassified TRIM (tripartite motif) family of proteins that do not have RING fingers and thus lack the characteristic tripartite (RING (R), B-box, and coiled coil (CC)) RBCC motif. It contains a Bbox2 zinc finger as well as a C-terminal SPRY/B30.2 domain. The type 2 B-box (Bbox2) zinc finger is characterized by a CHC3H2 zinc-binding consensus motif.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....
gi 1039768890  20 WRCPEHSERPAELFCRRCGRCVCALCPVLGAHRGHPVGLAEEEA 63
Cdd:cd19768     1 RCCPEHKDRPLELFCKTCKRCVCALCPILGQHRGHDVRLIDEEA 44

B-box-type 2 zinc finger found in tripartite motif-containing protein 65 (TRIM65), B box and SPRY domain-containing protein (BSPRY) and similar proteins; The family includes TRIM65 and BSPRY. TRIM65 is an E3 ubiquitin-protein ligase that interacts with the innate immune receptor MDA5 enhancing its ability to stimulate interferon-beta signaling. It functions as a potential oncogenic protein that negatively regulates p53 through ubiquitination, providing insight into development of novel approaches targeting TRIM65 for non-small cell lung carcinoma (NSCLC) treatment, and also overcoming chemotherapy resistance. Moreover, TRIM65 negatively regulates microRNA-driven suppression of mRNA translation by targeting TNRC6 proteins for ubiquitination and degradation. BSPRY is a regulatory protein for maintaining calcium homeostasis. It may regulate epithelial calcium transport by inhibiting TRPV5 activity. The type 2 B-box (Bbox2) zinc finger is characterized by a CHC3H2 zinc-binding consensus motif.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....
gi 1039768890  20 WRCPEHsERPAELFCRRCGRCVCALCPVLGAHRGHPVGLAEEEA 63
Cdd:cd19793     1 ELCPEH-GRELELYCRTEKRCVCAQCASKGECRGHRVTLLEERA 43

B-Box-type zinc finger;

                           10        20        30
                   ....*....|....*....|....*....|....*....
gi 1039768890   20 WRCPEHSERPAELFCRRCGRCVCALCpVLGAHRGHPVGL 58
Cdd:smart00336   4 PKCDSHGDEPAEFFCEECGALLCRTC-DEAEHRGHTVVL 41

B-box-type 2 zinc finger found in tripartite motif-containing protein 59 (TRIM59) and similar proteins; TRIM59, also known as TRIM57, or RING finger protein 104 (RNF104) or tumor suppressor TSBF-1, is a putative E3 ubiquitin-protein ligase that functions as a novel multiple cancer biomarker for immunohistochemical detection of early tumorigenesis. It is upregulated in gastric cancer and promotes gastric carcinogenesis by interacting with and targeting the P53 tumor suppressor for its ubiquitination and degradation. It also acts as a novel accessory molecule involved in cytotoxicity of BCG-activated macrophages (BAM). Moreover, TRIM59 may serve as a multifunctional regulator for innate immune signaling pathways. It interacts with ECSIT and negatively regulates nuclear factor-kappaB (NF- kappa B) and interferon regulatory factor (IRF)-3/7-mediated signal pathways. TRIM59 belongs to the C-XI subclass of TRIM (tripartite motif) family of proteins that are defined by an N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a RING finger, Bbox2, and a coiled coil region. In addition, TRIM59 contains a C-terminal transmembrane domain.

                          10        20        30
                  ....*....|....*....|....*....|....*
gi 1039768890  22 CPEHSERPAELFCRRCGRCVCALCPVLGAHRGHPV 56
Cdd:cd19790     3 CPEHYRQPLNLFCLLDRKLICGQCLTVGQHQGHPI 37

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.

                          10        20        30
                  ....*....|....*....|....*....|....*
gi 1039768890  22 CPEHSERPAELFCRRCGRCVCALCPVLGAHRGHPV 56
Cdd:cd19778     3 CPEHEMEKVNMYCEACRRPVCHLCKLGGSHANHRV 37

B-box-type 2 zinc finger found in tripartite motif-containing protein TRIM50, TRIM73, TRIM74 and similar proteins; TRIM50 is a stomach-specific E3 ubiquitin-protein ligase, encoded by the Williams-Beuren syndrome (WBS) TRIM50 gene, which regulates vesicular trafficking for acid secretion in gastric parietal cells. It colocalizes, interacts with, and increases the level of p62/SQSTM1, a multifunctional adaptor protein implicated in various cellular processes including the autophagy clearance of polyubiquitinated protein aggregates. It also promotes the formation and clearance of aggresome-associated polyubiquitinated proteins through the interaction with the histone deacetylase 6 (HDAC6), a tubulin specific deacetylase that regulates microtubule-dependent aggresome formation. TRIM50 can be acetylated by PCAF and p300. TRIM50 belongs to the C-IV subclass of TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a RING finger, 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. The type 2 B-box (Bbox2) zinc finger is characterized by a CHC3H2 zinc-binding consensus motif. The family also includes two paralogs of TRIM50, tripartite motif-containing protein 73 (TRIM73), also known as tripartite motif-containing protein 50B (TRIM50B), and tripartite motif-containing protein 74 (TRIM74), also known as tripartite motif-containing protein 50C (TRIM50C), both of which are WBS-related genes encoding proteins and may also act as E3 ligases. In contrast with TRIM50, TRIM73 and TRIM74 belong to the C-V subclass of TRIM family of proteins that are defined by the N-terminal RBCC domains only.

                          10        20        30
                  ....*....|....*....|....*....|....*
gi 1039768890  22 CPEHsERPAELFCRRCGRCVCALCPVLGAHRGHPV 56
Cdd:cd19787     3 CPHH-HNPLSLFCEKDQEVICGLCGLIGSHRQHKI 36

second B-box-type 2 zinc finger found in tripartite motif-containing protein 23 (TRIM23) and similar proteins; TRIM23, also known as ADP-ribosylation factor domain-containing protein 1, GTP-binding protein ARD-1, or RING finger protein 46 (RNF46), is an E3 ubiquitin-protein ligase belonging to the C-IX subclass of TRIM (tripartite motif) family of proteins that are defined by an N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a RING finger, two Bbox2, and a coiled coil region, as well as C-terminal ADP ribosylation factor (ARF) domains. The type 2 B-box (Bbox2) zinc finger is characterized by a CHC3H2 zinc-binding consensus motif. TRIM23 is involved in nuclear factor (NF)-kappaB activation. It mediates atypical lysine 27 (K27)-linked polyubiquitin conjugation to NF-kappaB essential modulator NEMO, also known as IKKgamma, which plays an important role in the NF-kappaB pathway, and this conjugation is essential for TLR3- and RIG-I/MDA5-mediated antiviral innate and inflammatory responses. It also regulates adipocyte differentiation via stabilization of the adipogenic activator peroxisome proliferator-activated receptor gamma (PPARgamma) through atypical ubiquitin conjugation to PPARgamma. Moreover, TRIM23 interacts with and polyubiquitinates yellow fever virus (YFV) NS5 to promote its binding to STAT2 and trigger type I interferon (IFN-I) signaling inhibition.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*..
gi 1039768890  21 RCPEHSERPAELFCR----RCGRCVCALCPVLGAHRGHPVGLAEEEA 63
Cdd:cd19774     4 KCPIHPDHLIEFVCLeedcQESPLMCIICKEYGKHQGHKHELLEEEA 50

B-box-type 2 zinc finger found in tripartite motif-containing protein 45 (TRIM45) and similar proteins; TRIM45, also known as RING finger protein 99 (RNF99), is a novel receptor for activated C-kinase (RACK1)-interacting protein that suppresses transcriptional activities of Elk-1 and AP-1 and downregulates mitogen-activated protein kinase (MAPK) signal transduction by inhibiting RACK1/PKC (protein kinase C) complex formation. It also negatively regulates tumor necrosis factor alpha (TNFalpha)-induced nuclear factor-kappaB (NF-kappa B)-mediated transcription and suppresses cell proliferation. TRIM45 belongs to the C-X subclass of TRIM (tripartite motif) 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 region, as well as a filamin-type immunoglobulin (IG-FLMN) domain and NHL repeats positioned C-terminal to the RBCC domain. The type 2 B-box (Bbox2) zinc finger is characterized by a CHC3H2 zinc-binding consensus motif.

                          10        20        30
                  ....*....|....*....|....*....|....*
gi 1039768890  22 CPEHSERPAELFCRRCGRCVCALCpVLGAHRGHPV 56
Cdd:cd19785     4 CPFHPAEELRLFCETCDKPVCRDC-VLVEHRGHQC 37

B-box-type 2 zinc finger 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, and 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 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.

                          10        20        30
                  ....*....|....*....|....*....|.
gi 1039768890  22 CPEHSERPAELFCRRCGRCVCALCPVLGAHR 52
Cdd:cd19833     3 CEEHEEEKINIYCLSCEVPTCSLCKVFGAHK 33

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.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....
gi 1039768890  20 WRCPEHSERPAELFCRRCGRCVCALCpVLGAHRGHPVglaeeeaVRVQKLIQDC 73
Cdd:cd19796     2 SYCEIHEHEVLRLYCDTCSVPICREC-TMGEHRGHSF-------IYLQEAVQDS 47

B-box-type 2 zinc finger 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 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 signalling 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 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.

                          10        20        30
                  ....*....|....*....|....*....|..
gi 1039768890  21 RCPEHSERPAELFCRRCGRCVCALCPVLGAHR 52
Cdd:cd19832     2 MCEEHEEERINIYCLNCEVPTCSLCKVFGAHK 33

B-box-type 2 zinc finger found in tripartite motif-containing protein 72 (TRIM72) and similar proteins; TRIM72, also known as Mitsugumin-53 (MG53), is a muscle-specific protein that plays a central role in cell membrane repair by nucleating the assembly of the repair machinery at muscle injury sites. It is required in repair of alveolar epithelial cells under plasma membrane stress failure. It interacts with dysferlin to regulate sarcolemmal repair. Upregulation of TRIM72 develops obesity, systemic insulin resistance, dyslipidemia, and hyperglycemia, as well as induces diabetic cardiomyopathy through transcriptional activation of peroxisome proliferation-activated receptor alpha (PPAR-alpha) signaling pathway. Compensation for the absence of AKT signaling by ERK signaling during TRIM72 overexpression leads to pathological hypertrophy. Moreover, TRIM72 functions as a novel negative feedback regulator of myogenesis via targeting insulin receptor substrate-1 (IRS-1). It is transcriptionally activated by the synergism of myogenin (MyoD) and myocyte enhancer factor 2 (MEF2). TRIM72 belongs to the C-IV subclass of TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a RING 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. The type 2 B-box (Bbox2) zinc finger is characterized by a CHC3H2 zinc-binding consensus motif.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|
gi 1039768890  22 CPEHSErPAELFCRRCGRCVCALCPVLGAHRGHPVGLAEE 61
Cdd:cd19797     3 CEEHLD-PLSVYCEQDRALICGVCASLGKHKGHNIITAAE 41

B-box-type 2 zinc finger found in midline-2 (MID2) and similar proteins; MID2, also known as midin-2, midline defect 2, RING finger protein 60 (RNF60), or tripartite motif-containing protein 1 (TRIM1), is a probable E3 ubiquitin-protein ligase that is highly related to MID1 that associate with cytoplasmic microtubules along their length and throughout the cell cycle. Like MID1, MID2 associates with the microtubule network and may at least partially compensate for the loss of MID1. Both MID1 and MID2 interacts with Alpha 4, which is a regulatory subunit of PP2-type phosphatases, such as PP2A, and an integral component of the rapamycin-sensitive signaling pathway. MID2 can also substitute for MID1 to control exocytosis of lytic granules in cytotoxic T cells. It heterodimerizes in vitro with its paralog MID1. Loss-of-function mutations in MID2 lead to the human X-linked intellectual disability (XLID). MID2 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 (carboxy-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.

                          10        20        30
                  ....*....|....*....|....*....|....*
gi 1039768890  22 CPEHSERPAELFCRRCGRCVCALCPVLGAHRGHPV 56
Cdd:cd19823     3 CLEHENEKVNMYCVVDDQLICALCKLVGRHRDHQV 37

4Fe-4S dicluster domain; This family includes proteins containing domains which bind to iron-sulfur clusters. Members include bacterial ferredoxins, various dehydrogenases, and various reductases. The structure of the domain is an alpha-antiparallel beta sandwich.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|
gi 1039768890  33 FCRRCGRCVcALCPVLGAHRGHP------VGLAEEEAVRVQKLIQDCLEC 76
Cdd:pfam13534   1 RCIQCGCCV-DECPRYLLNGDEPkklmraAYLGDLEELQANKVANLCSEC 49

B-box-type 2 zinc finger found in tripartite motif-containing protein 37 (TRIM37) and similar proteins; TRIM37, also known as Mulibrey nanism protein, 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 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 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. The type 2 B-box (Bbox2) zinc finger is characterized by a CHC3H2 zinc-binding consensus motif.

                          10        20        30
                  ....*....|....*....|....*....|....
gi 1039768890  22 CPEHSErPAELFCRRCGRCVCALCPVL-GAHRGH 54
Cdd:cd19779     3 CETHNE-KLSVYCWTCKKCICHQCALWgGTHSGH 35

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.

                          10        20        30
                  ....*....|....*....|....*....|....*
gi 1039768890  22 CPEHSERPAELFCRRCGRCVCALCPVLGAHRGHPV 56
Cdd:cd19788     2 CEEHEEEKINIYCLTCEVPTCSMCKVFGAHKDCEV 36