B-box-type zinc finger superfamily; The B-box-type zinc finger is a short zinc binding domain of around 40 amino acid residues in length. It has been found in transcription factors, ribonucleoproteins and proto-oncoproteins, such as in TRIM (tripartite motif) proteins that consist of an N-terminal RING finger (originally called an A-box), followed by 1-2 B-box domains and a coiled-coil domain (also called RBCC for Ring, B-box, Coiled-Coil). The B-box-type zinc finger often presents in combination with other motifs, like RING zinc finger, NHL motif, coiled-coil or RFP domain in functionally unrelated proteins, most likely mediating protein-protein interactions. Based on different consensus sequences and the spacing of the 7-8 zinc-binding residues, B-box-type zinc fingers can be divided into two groups, type 1 (Bbox1: C6H2) and type 2 (Bbox2: CHC3H2).

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gi 1720428103  18 CGTHPEPSQFFSDDDQVIVCSKCFQSPEHKQHGAYGIQEAA 58
Cdd:cd19795     4 CERHKEKLNLFCEEDQELLCVVCEQSPEHKAHTVVPVEEAA 44

B-box-type 2 zinc finger found in tripartite motif-containing protein 68 (TRIM68) and similar proteins; TRIM68, also known as RING finger protein 137 (RNF137) or SSA protein SS-56 (SS-56), is an E3 ubiquitin-protein ligase that negatively regulates Toll-like receptor (TLR)- and RIG-I-like receptor (RLR)-driven type I interferon production by degrading TRK fused gene (TFG), a novel driver of IFN-beta downstream of anti-viral detection systems. It also functions as a cofactor for androgen receptor-mediated transcription by regulating ligand-dependent transcription of androgen receptor in prostate cancer cells. Moreover, TRIM68 is a cellular target of autoantibody responses in Sjogren's syndrome (SS), as well as systemic lupus erythematosus (SLE). It is also an auto-antigen for T cells in SS and SLE. TRIM68 belongs 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 two coiled coil domains, 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.

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gi 1720428103  18 CGTHPEPSQFFSDDDQVIVCSKCFQSPEHKQHGAYGIQEAA 58
Cdd:cd19795     4 CERHKEKLNLFCEEDQELLCVVCEQSPEHKAHTVVPVEEAA 44

B-box-type 2 zinc finger found in tripartite motif-containing protein 68 (TRIM68) and similar proteins; TRIM68, also known as RING finger protein 137 (RNF137) or SSA protein SS-56 (SS-56), is an E3 ubiquitin-protein ligase that negatively regulates Toll-like receptor (TLR)- and RIG-I-like receptor (RLR)-driven type I interferon production by degrading TRK fused gene (TFG), a novel driver of IFN-beta downstream of anti-viral detection systems. It also functions as a cofactor for androgen receptor-mediated transcription by regulating ligand-dependent transcription of androgen receptor in prostate cancer cells. Moreover, TRIM68 is a cellular target of autoantibody responses in Sjogren's syndrome (SS), as well as systemic lupus erythematosus (SLE). It is also an auto-antigen for T cells in SS and SLE. TRIM68 belongs 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 two coiled coil domains, 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.

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gi 1720428103  18 CGTHPEPSQFFSDDDQVIVCSKCFQSPEHKQHGAYGIQEAA 58
Cdd:cd19795     4 CERHKEKLNLFCEEDQELLCVVCEQSPEHKAHTVVPVEEAA 44

B-box-type 2 zinc finger found in tripartite motif-containing protein 40 (TRIM40) and similar proteins; TRIM40, also termed probable E3 NEDD8-protein ligase, or RING finger protein 35, may function as an E3 ubiquitin-protein ligase of the NEDD8 conjugation pathway. It promotes neddylation of IKBKG/NEMO, stabilizing NFKBIA, and inhibiting NF-kappaB nuclear translocation and activity. TRIM40 belongs to the C-V 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. The type 2 B-box (Bbox2) zinc finger is characterized by a CHC3H2 zinc-binding consensus motif.

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gi 1720428103  18 CGTHPEPSQFFSDDDQVIVCSKCFQSPEHKQH 49
Cdd:cd19781     5 CQLHEKKVEWFCEEDQVLLCEECLKSPEHQSH 36

B-box-type 2 zinc finger found in tripartite motif-containing proteins TRIM7, TRIM27 and similar proteins; The family includes TRIM7 and TRIM27, both of which belong to the C-IV 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, 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. TRIM7, also known as glycogenin-interacting protein (GNIP) or RING finger protein 90 (RNF90), is an E3 ubiquitin-protein ligase that mediates c-Jun/AP-1 activation by Ras signalling. Its phosphorylation and activation by MSK1 in response to direct activation by the Ras-Raf-MEK-ERK pathway can stimulate TRIM7 E3 ubiquitin ligase activity in mediating Lys63-linked ubiquitination of the AP-1 coactivator RACO-1, leading to RACO-1 protein stabilization. Moreover, TRIM7 binds and activates glycogenin, the self-glucosylating initiator of glycogen biosynthesis. TRIM27, also termed RING finger protein 76 (RNF76), or RET finger protein (RFP), or zinc finger protein RFP, is a nuclear E3 ubiquitin-protein ligase that is highly expressed in testis and in various tumor cell lines. Expression of TRIM27 is associated with prognosis of colon and endometrial cancers. TRIM27 was first identified as a fusion partner of the RET receptor tyrosine kinase. It functions as a transcriptional repressor and associates with several proteins involved in transcriptional activity, such as enhancer of polycomb 1 (Epc1), a member of the Polycomb group proteins, and Mi-2beta, a main component of the nucleosome remodeling and deacetylase (NuRD) complex, and the cell cycle regulator retinoblastoma protein (RB1). It also interacts with HDAC1, leading to downregulation of thioredoxin binding protein 2 (TBP-2), which inhibits the function of thioredoxin. Moreover, TRIM27 mediates Pax7-induced ubiquitination of MyoD in skeletal muscle atrophy. It also inhibits muscle differentiation by modulating serum response factor (SRF) and Epc1. Furthermore, TRIM27 promotes non-canonical polyubiquitination of PTEN, a lipid phosphatase that catalyzes PtdIns(3,4,5)P3 (PIP3) to PtdIns(4,5)P2 (PIP2). It is an IKKepsilon-interacting protein that regulates IkappaB kinase (IKK) function and negatively regulates signaling involved in the antiviral response and inflammation. In addition, TRIM27 forms a protein complex with MBD4 or MBD2 or MBD3, and thus plays an important role in the enhancement of transcriptional repression through MBD proteins in tumorigenesis, spermatogenesis, and embryogenesis. It is also a component of an estrogen receptor 1 (ESR1) regulatory complex, and is involved in estrogen receptor-mediated transcription in MCF-7 cells. Meanwhile, TRIM27 interacts with the hinge region of chromosome 3 protein (SMC3), a component of the multimeric cohesin complex that holds sister chromatids together and prevents their premature separation during mitosis.

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gi 1720428103  18 CGTHPEPSQFFSDDDQVIVCSKCFQSPEHKQHGAYGIQEAAE 59
Cdd:cd19762     3 CEKHQEPLKLFCKEDKRPICVVCDRSREHRHHTVLPVEEAAQ 44

B-box-type 2 zinc finger found in tripartite motif-containing protein 8 (TRIM8) and similar proteins; TRIM8, also known as glioblastoma-expressed RING finger protein (GERP) or RING finger protein 27 (RNF27), is a probable E3 ubiquitin-protein ligase that may promote proteasomal degradation of suppressor of cytokine signaling 1 (SOCS1) and further regulate interferon-gamma signaling. It functions as a new p53 modulator that stabilizes p53, impairing its association with MDM2 and inducing the reduction of cell proliferation. TRIM8 deficit dramatically impairs p53 stabilization and activation in response to chemotherapeutic drugs. TRIM8 also modulates tumor necrosis factor-alpha (TNFalpha) and interleukin-1beta (IL-1beta)-triggered nuclear factor-kappaB (NF-kappa B) activation by targeting transforming growth factor beta (TGFbeta) activated kinase 1 (TAK1) for K63-linked polyubiquitination. Moreover, TRIM8 modulates translocation of phosphorylated STAT3 into the nucleus through interaction with Hsp90beta and consequently regulates transcription of Nanog in embryonic stem cells. It also interacts with protein inhibitor of activated STAT3 (PIAS3), which inhibits IL-6-dependent activation of STAT3. TRIM8 belongs to the C-V subclass of nuclear 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 domain, as well as an uncharacterized region positioned C-terminal to the RBCC domain. The coiled coil domain is required for homodimerization and the region immediately C-terminal to the RING motif is sufficient to mediate the interaction with SOCS1. The type 2 B-box (Bbox2) zinc finger is characterized by a CHC3H2 zinc-binding consensus motif.

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gi 1720428103  18 CGTHPEPSQFFSDDDQVIVCSKCFQSPEHKQHGAY 52
Cdd:cd19763     4 CPQHDAYRLYHCEAEQVAVCEYCCYEGTHQGHSIC 38

B-box-type 2 zinc finger found in Xenopus laevis nuclear factor 7 (xNF7) and similar proteins; xNF7 is a maternally expressed novel zinc finger nuclear phosphoprotein. It acts as a transcription factor that determines dorsal-ventral body axis. xNF7 harbors a B-box motif that shows high sequence similarity with B-Box-type zinc finger 2 found in tripartite motif-containing proteins (TRIMs). The type 2 B-box (Bbox2) zinc finger is characterized by a CHC3H2 zinc-binding consensus motif.

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gi 1720428103  18 CGTHPEPSQFFSDDDQVIVCSKCFQSPEHKQH 49
Cdd:cd19800     3 CSEHDEPLKLFCKDDKRLICVICRDSRKHRGH 34

B-box-type 2 zinc finger found in tripartite motif-containing proteins, TRIM10, TRIM15, TRIM26, TRIM31 and similar proteins; This family includes TRIM10, TRIM15, TRIM26 and TRIM31. TRIM10, also known as B30-RING finger protein (RFB30), RING finger protein 9 (RNF9), or hematopoietic RING finger 1 (HERF1), is a novel hematopoiesis-specific RING finger protein required for terminal differentiation of erythroid cells. TRIM15, also termed RING finger protein 93 (RNF93), or zinc finger protein 178 (ZNF178), or zinc finger protein B7 (ZNFB7), is a focal adhesion protein that regulates focal adhesion disassembly. It localizes to focal contacts in a myosin-II-independent manner by an interaction between its coiled-coil domain and the LD2 motif of paxillin. TRIM15 can also associate with coronin 1B, cortactin, filamin binding LIM protein1, and vasodilator-stimulated phosphoprotein, which are involved in actin cytoskeleton dynamics. As an additional component of the integrin adhesome, it regulates focal adhesion turnover and cell migration. TRIM26, also known as acid finger protein (AFP), RING finger protein 95 (RNF95), or zinc finger protein 173 (ZNF173), is an E3 ubiquitin-protein ligase that negatively regulates interferon-beta production and antiviral response through polyubiquitination and degradation of nuclear transcription factor IRF3. It functions as an important regulator for RNA virus-triggered innate immune response by bridging TBK1 to NEMO (NF-kappaB essential modulator, also known as IKKgamma) and mediating TBK1 activation. It also acts as a novel tumor suppressor of hepatocellular carcinoma by regulating cancer cell proliferation, colony forming ability, migration, and invasion. TRIM31 is an E3 ubiquitin-protein ligase that primarily localizes to the cytoplasm, but is also associated with the mitochondria. It can negatively regulate cell proliferation and may be a potential biomarker of gastric cancer as it is overexpressed from the early stage of gastric carcinogenesis. TRIM31 is downregulated in non-small cell lung cancer and serves as a potential tumor suppressor. It interacts with p52 (Shc) and inhibits Src-induced anchorage-independent growth. TRIM10, TRIM15 and TRIM26 belong 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. TRIM31 belongs to the C-V subclass of TRIM family of proteins. The type 2 B-box (Bbox2) zinc finger is characterized by a CHC3H2 zinc-binding consensus motif.

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gi 1720428103  18 CGTHPEPSQFFSDDDQVIVCSKCFQSPEHKQH 49
Cdd:cd19765     3 CEEHGEKIHFFCEDDGKFLCVVCRESREHRTH 34