Death Domain Superfamily of protein-protein interaction domains; The Death Domain (DD) superfamily includes the DD, Pyrin, CARD (Caspase activation and recruitment domain) and DED (Death Effector Domain) families. DDs are protein-protein interaction domains found in a variety of domain architectures. Their common feature is that they form homodimers by self-association or heterodimers by associating with other members of the DD superfamily. They serve as adaptors in signaling pathways and can recruit other proteins into signaling complexes. They are prominent components of the programmed cell death (apoptosis) pathway and are found in a number of other signaling pathways including those that impact innate immunity, inflammation, differentiation, and cancer.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1935598078   7 DHLLNTLEELLPYELEKFKFKLHTTSLEkGHSRIPLSLVKMARPIKLTRLLLTYYGEEYAVRLTLQILRATNQRQLAEEL 86
Cdd:cd08321     2 DLLLDALEDLGEEELKKFKWKLRDIPLE-GYPRIPRGKLENADRVDLVDLLVSYYGEDYAVEVTVEVLRAINQNDLAEKL 80

                  ..
gi 1935598078  87 HK 88
Cdd:cd08321    81 QK 82

Pyrin Death Domain found in ASC; Pyrin Death Domain found in ASC (Apoptosis-associated speck-like protein containing a CARD) and similar proteins. ASC is an adaptor molecule that functions in the assembly of the 'inflammasome', a multiprotein platform, which is responsible for caspase-1 activation and regulation of IL-1beta maturation. ASC contains two domains from the Death Domain (DD) superfamily, an N-terminal pyrin-like domain and a C-terminal Caspase activation and recruitment domain (CARD). Through these 2 domains, ASC serves as an adaptor for inflammasome integrity and oligomerizes to form supramolecular assemblies. Included in this family is human PYNOD (also known as NLRP10 or NOD8) which via its Pyrin domain suppresses oligomerization of ASC, and ASC-mediated NF-kappaB activation. Other members of this subfamily are associated with ATPase domains and their function remains unknown. In general, Pyrin is a subfamily of the DD superfamily and functions in several signaling pathways. DDs are protein-protein interaction domains found in a variety of domain architectures. Their common feature is that they form homodimers by self-association or heterodimers by associating with other members of the DD superfamily including CARD and Death Effector Domain (DED). They serve as adaptors in signaling pathways and can recruit other proteins into signaling complexes.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1935598078   7 DHLLNTLEELLPYELEKFKFKLHTTSLEkGHSRIPLSLVKMARPIKLTRLLLTYYGEEYAVRLTLQILRATNQRQLAEEL 86
Cdd:cd08321     2 DLLLDALEDLGEEELKKFKWKLRDIPLE-GYPRIPRGKLENADRVDLVDLLVSYYGEDYAVEVTVEVLRAINQNDLAEKL 80

                  ..
gi 1935598078  87 HK 88
Cdd:cd08321    81 QK 82

B-Box-type zinc finger;

                           10        20        30        40
                   ....*....|....*....|....*....|....*....|
gi 1935598078  442 PQCPRHMKQVQLLFCEDHREPICLICRLSqEHQGHRVRPI 481
Cdd:smart00336   4 PKCDSHGDEPAEFFCEECGALLCRTCDEA-EHRGHTVVLL 42

Pyrin Death Domain found in ASC; Pyrin Death Domain found in ASC (Apoptosis-associated speck-like protein containing a CARD) and similar proteins. ASC is an adaptor molecule that functions in the assembly of the 'inflammasome', a multiprotein platform, which is responsible for caspase-1 activation and regulation of IL-1beta maturation. ASC contains two domains from the Death Domain (DD) superfamily, an N-terminal pyrin-like domain and a C-terminal Caspase activation and recruitment domain (CARD). Through these 2 domains, ASC serves as an adaptor for inflammasome integrity and oligomerizes to form supramolecular assemblies. Included in this family is human PYNOD (also known as NLRP10 or NOD8) which via its Pyrin domain suppresses oligomerization of ASC, and ASC-mediated NF-kappaB activation. Other members of this subfamily are associated with ATPase domains and their function remains unknown. In general, Pyrin is a subfamily of the DD superfamily and functions in several signaling pathways. DDs are protein-protein interaction domains found in a variety of domain architectures. Their common feature is that they form homodimers by self-association or heterodimers by associating with other members of the DD superfamily including CARD and Death Effector Domain (DED). They serve as adaptors in signaling pathways and can recruit other proteins into signaling complexes.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1935598078   7 DHLLNTLEELLPYELEKFKFKLHTTSLEkGHSRIPLSLVKMARPIKLTRLLLTYYGEEYAVRLTLQILRATNQRQLAEEL 86
Cdd:cd08321     2 DLLLDALEDLGEEELKKFKWKLRDIPLE-GYPRIPRGKLENADRVDLVDLLVSYYGEDYAVEVTVEVLRAINQNDLAEKL 80

                  ..
gi 1935598078  87 HK 88
Cdd:cd08321    81 QK 82

B-box-type 2 zinc finger found in tripartite motif-containing protein 11 (TRIM11) and similar proteins; TRIM11, also known as protein BIA1, or RING finger protein 92 (RNF92), is an E3 ubiquitin-protein ligase involved in the development of the central nervous system. It is overexpressed in high-grade gliomas and promotes proliferation, invasion, migration and glial tumor growth. TRIM11 acts as a potential therapeutic target for congenital central hypoventilation syndrome (CCHS) through mediating the degradation of CCHS-associated polyalanine-expanded Phox2b. Trim11 modulates the function of neurogenic transcription factor Pax6 through the ubiquitin-proteosome system, and thus plays an essential role for Pax6-dependent neurogenesis. It also binds to and destabilizes a key component of the activator-mediated cofactor complex (ARC105), humanin, a neuroprotective peptide against Alzheimer's disease-relevant insults, and further regulates ARC105 function in transforming growth factor beta (TGFbeta) signaling. Moreover, TRIM11 negatively regulates retinoic acid-inducible gene-I (RIG-I)-mediated interferon-beta (IFNbeta) production and antiviral activity by targeting TANK-binding kinase-1 (TBK1). It may contribute to the endogenous restriction of retroviruses in cells. It enhances N-tropic murine leukemia virus (N-MLV) entry by interfering with Ref1 restriction. It also suppresses the early steps of human immunodeficiency virus HIV-1 transduction, resulting in decreased reverse transcripts. TRIM11 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 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.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|..
gi 1935598078 444 CPRHMKQVQLlFCEDHREPICLICRLSQEHQGHRVRPIEEAA 485
Cdd:cd19766     3 CGKHREPLKL-FCKDHEALLCVVCERSREHWGHRVVPAEEAA 43

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.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|..
gi 1935598078 444 CPRHMKQVQLlFCEDHREPICLICRLSQEHQGHRVRPIEEAA 485
Cdd:cd19762     3 CEKHQEPLKL-FCKEDKRPICVVCDRSREHRHHTVLPVEEAA 43

Pyrin death domain found in NALP proteins; Pyrin Death Domain found in NALP (NACHT, LRR and PYD domains) proteins including NALP1 (CARD7, NLRP1), NALP3 (NLRP3, Cryopyrin, CIAS1), and NALP12 (NLRP12, Monarch-1), among others. Mammals contains at least 14 NALP proteins, named NALP1-14 (or NLRP1-14). NALPs are members of the NBS-LRR family of proteins possessing a tripartite domain structure including a C-terminal LRR (leucine-rich repeats), a central nucleotide-binding site (NBS) domain or NACHT (for neuronal apoptosis inhibitor protein, CIITA, HET-E and TP1), and an N-terminal protein-protein interaction domain, which is a Pyrin domain in the case of NALPs. The NBS-LRR family is also referred to as the NLR (Nod-like Receptor) or CATERPILLAR (for CARD, transcription enhancer, R-(purine)-binding, pyrin, lots of LRRs) family. NALP1 contains an additional Caspase activation and recruitment domain (CARD) at the C-terminus. NALP1 and NALP3 are both involved in the assembly of the 'inflammasome', a multiprotein platform which is formed in response to infection or injury and is responsible for caspase-1 activation and regulation of IL-1beta maturation. NALP1-inflammasomes recognize specific substances while NALP3-inflammasomes responds to many diverse triggers. Mutations in the NALP3 gene are associated with a broad spectrum of autoinflammatory disorders including Muckle-Wells Syndrome (MWS), familial cold autoinflammatory syndrome (FCAS), and chronic neurologic cutaneous and articular syndrome (CINCA). NALP12 functions as a negative regulator of inflammation. In general, Pyrin is a subfamily of the Death Domain (DD) superfamily and functions in several signaling pathways. DDs are protein-protein interaction domains found in a variety of domain architectures. Their common feature is that they form homodimers by self-association or heterodimers by associating with other members of the DD superfamily including CARD and DED (Death Effector Domain). They serve as adaptors in signaling pathways and can recruit other proteins into signaling complexes.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1935598078  25 KFKLH--TTSLEKGHSRIPLSLVKMARPIKLTRLLLTYYGEEYAVRLTLQILRATNQRQLAE 84
Cdd:cd08320    15 KFKLLlkEESLEGGLKPIPWTEVKKADGEELAELLTEHYPEQQAWDVALSIFEKMNRTDLCE 76

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.

                          10        20        30
                  ....*....|....*....|....*....|....*...
gi 1935598078 444 CPRHMKQVQLlFCEDHREPICLICRLSQEHQGHRVRPI 481
Cdd:cd19800     3 CSEHDEPLKL-FCKDDKRLICVICRDSRKHRGHRFLPV 39

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.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|...
gi 1935598078 443 QCPRHMKQVQLlFCEDHREPICLICRLSQEHQGHRVRPIEEAA 485
Cdd:cd19795     3 LCERHKEKLNL-FCEEDQELLCVVCEQSPEHKAHTVVPVEEAA 44

B-box-type 2 zinc finger found in tripartite motif-containing proteins TRIM39, TRIM58 and similar proteins; The family includes TRIM39 and TRIM58, both of which 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 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. TRIM39, also termed RING finger protein 23 (RNF23), or testis-abundant finger protein, is an E3 ubiquitin-protein ligase that plays a role in controlling DNA damage-induced apoptosis through inhibition of the anaphase promoting complex (APC/C), a multiprotein ubiquitin ligase that controls multiple cell cycle regulators, including cyclins, geminin, and others. TRIM39 also functions as a regulator of several key processes in the proliferative cycle. It directly regulates p53 stability and modulates cell cycle progression and DNA damage responses via stabilization of p21. TRIM39 also negatively regulates the nuclear factor kappaB (NFkappaB)-mediated signaling pathway through stabilization of Cactin, an inhibitor of NFkappaB- and Toll-like receptor (TLR)-mediated transcription, which is induced by inflammatory stimulants such as tumor necrosis factor alpha (TNFalpha). TRIM39 is a MOAP-1-binding protein that can promote apoptosis signaling through stabilization of MOAP-1 via the inhibition of its poly-ubiquitination process. TRIM58, also known as protein BIA2, is an erythroid E3 ubiquitin-protein ligase induced during late erythropoiesis. It binds and ubiquitinates the intermediate chain of the microtubule motor dynein (DYNC1LI1/DYNC1LI2), stimulating the degradation of the dynein holoprotein complex. It may participate in the erythroblast enucleation process through regulation of nuclear polarization.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|...
gi 1935598078 442 PQCPRHmKQVQLLFCEDHREPICLICRLSQEHQGHRVRPIEEA 484
Cdd:cd19780     3 SLCARH-REALSLFCEEDQEAVCLVCEISHDHRAHTLVPLQDA 44

B-box-type 2 zinc finger found in tripartite motif-containing proteins, TRIM5, TRIM6, TRIM22, TRIM34, TRIM38 and similar proteins; The family includes TRIM5, TRIM6, TRIM22, TRIM34, and TRIM38, all of which belong 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 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. TRIM5, also termed RING finger protein 88 (RNF88), is a capsid-specific restriction factor that prevents infection from non-host-adapted retroviruses in a species-specific manner by binding to and destabilizing the retroviral capsid lattice before reverse transcription is completed. Its retroviral restriction activity correlates with the ability to activate TAK1-dependent innate immune signaling. TRIM5 also acts as a pattern recognition receptor that activates innate immune signaling in response to the retroviral capsid lattice. Moreover, TRIM5 plays a role in regulating autophagy through activation of autophagy regulator BECN1 by causing its dissociation from its inhibitors BCL2 and TAB2. It also plays a role in autophagy by acting as a selective autophagy receptor which recognizes and targets HIV-1 capsid protein p24 for autophagic destruction. TRIM6, also termed RING finger protein 89 (RNF89), is an E3-ubiquitin ligase that cooperates with the E2-ubiquitin conjugase UbE2K to catalyze the synthesis of unanchored K48-linked polyubiquitin chains, and further stimulates the interferon-I kappa B kinase epsilon (IKKepsilon) kinase-mediated antiviral response. It also regulates the transcriptional activity of Myc during the maintenance of embryonic stem (ES) cell pluripotency, and may act as a novel regulator for Myc-mediated transcription in ES cells. TRIM22, also termed 50 kDa-stimulated trans-acting factor (Staf-50), or RING finger protein 94 (RNF94), is an E3 ubiquitin-protein ligase that plays an integral role in the host innate immune response to viruses. It has been shown to inhibit the replication of a number of viruses, including HIV-1, hepatitis B, and influenza A. TRIM22 acts as a suppressor of basal HIV-1 long terminal repeat (LTR)-driven transcription by preventing transcription factor specificity protein 1 (Sp1) binding to the HIV-1 promoter. It also controls FoxO4 activity and cell survival by directing Toll-like receptor 3 (TLR3)-stimulated cells toward type I interferon (IFN) type I gene induction or apoptosis. Moreover, TRIM22 can activate the noncanonical nuclear factor-kappaB (NF-kappaB) pathway by activating I kappa B kinase alpha (IKKalpha). It also regulates nucleotide binding oligomerization domain containing 2 (NOD2)-dependent activation of interferon-beta signaling and nuclear factor-kappaB. TRIM34, also termed interferon-responsive finger protein 1, or RING finger protein 21 (RNF21), may function as an antiviral protein that contributes to the defense against retroviral infections. TRIM38, also known as RING finger protein 15 (RNF15) or zinc finger protein RoRet, is an E3 ubiquitin-protein ligase that promotes K63- and K48-linked ubiquitination of cellular proteins and also catalyzes self-ubiquitination. It negatively regulates tumor necrosis factor alpha (TNF-alpha) and interleukin-1beta-triggered nuclear factor-kappaB (NF-kappaB) activation by mediating lysosomal-dependent degradation of transforming growth factor beta (TGFbeta)-activated kinase 1 (TAK1)-binding protein (TAB)2/3, two critical components of the TAK1 kinase complex. It also inhibits TLR3/4-mediated activation of NF-kappaB and interferon regulatory factor 3 (IRF3) by mediating ubiquitin-proteasomal degradation of TNF receptor-associated factor 6 (Traf6) and NAK-associated protein 1 (Nap1), respectively. Moreover, TRIM38 negatively regulates TLR3-mediated interferon beta (IFN-beta) signaling by targeting ubiquitin-proteasomal degradation of TIR domain-containing adaptor inducing IFN-beta (TRIF). It functions as a valid target for autoantibodies in primary Sjogren's Syndrome.

                          10        20        30
                  ....*....|....*....|....*....|....*....
gi 1935598078 444 CPRHMKQVQLlFCEDHREPICLICRLSQEHQGHRVRPIE 482
Cdd:cd19761     3 CEHHGEKLLL-FCQEDGKVICWLCERSQEHRGHHTFLLE 40

B-box zinc finger;

                          10        20        30
                  ....*....|....*....|....*....|....*...
gi 1935598078 444 CPRHMKQVQLLFCEDHREPICLICrLSQEHQGHRVRPI 481
Cdd:pfam00643   6 CPEHEEEPLTLYCNDCQELLCEEC-SVGEHRGHTVVPL 42

B-box-type 2 zinc finger found in tripartite motif-containing proteins, TRIM16, TRIM29, TRIM47 and similar proteins; This family includes a group of tripartite motif-containing proteins, such as TRIM16, TRIM29 and TRIM47. TRIM16, also termed estrogen-responsive B box protein (EBBP), is a regulator that may play a role in the regulation of keratinocyte differentiation. It may also act as a tumor suppressor through affecting cell proliferation and migration or tumorigenicity in carcinogenesis. TRIM29, also termed ataxia telangiectasia group D-associated protein (ATDC), plays a crucial role in the regulation of macrophage activation in response to viral or bacterial infections within the respiratory tract. TRIM47, also known as gene overexpressed in astrocytoma protein (GOA) or RING finger protein 100 (RNF100), plays an important role in the process of dedifferentiation that is associated with astrocytoma tumorigenesis. TRIM16 and TRIM29 belong 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. TRIM47 belongs to the C-IV subclass of TRIM 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 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.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*.
gi 1935598078 444 CPRHmKQVQLLFCEDHREPICLICRLsQEHQGHRVRPIEEAALQYK 489
Cdd:cd19769     3 CPIH-KKPLELFCRTDQMCICELCAK-EEHRGHDVVTVEEEREKKE 46

B-box-type 2 zinc finger found in tripartite motif-containing protein 21 (TRIM21) and similar proteins; TRIM21, also known as 52 kDa Ro protein, 52 kDa ribonucleoprotein autoantigen Ro/SS-A, Ro(SS-A), RING finger protein 81 (RNF81), or Sjoegren's syndrome type A antigen (SS-A), is a ubiquitously expressed E3 ubiquitin-protein ligase and a high affinity antibody receptor uniquely expressed in the cytosol of mammalian cells. As a cytosolic Fc receptor, TRIM21 binds the Fc of virus-associated antibodies and targets the complex in the cytosol for proteasomal degradation in a process known as antibody-dependent intracellular neutralization (ADIN), and provides an intracellular immune response to protect host defense against pathogen infection. It shows remarkably broad isotype specificity as it does not only bind IgG, but also IgM and IgA. Moreover, TRIM21 promotes the cytosolic DNA sensor cGAS and the cytosolic RNA sensor RIG-I sensing of viral genomes during infection by antibody-opsonized virus. It stimulates inflammatory signaling and activates innate transcription factors, such as nuclear factor-kappaB (NF-kappaB). TRIM21 also plays an essential role in p62-regulated redox homeostasis, suggesting a viable target for treating pathological conditions resulting from oxidative damage. Furthermore, TRIM21 may have implications for various autoimmune diseases associated uncontrolled antiviral signaling through the regulation of Nmi-IFI35 complex-mediated inhibition of innate antiviral response. TRIM21 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.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|
gi 1935598078 443 QCPRHMKQVQLlFCEDHREPICLICRLSQEHQGHRVRPIE 482
Cdd:cd19772     2 RCAVHGERLHL-FCEEDQKALCLVCAQSQKHRDHAMVPIE 40

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        40
                  ....*....|....*....|....*....|....*....|.
gi 1935598078 444 CPRHMKQVQLLFCEDHREPICLICRLSQEHQGHRVRPIEEA 484
Cdd:cd19778     3 CPEHEMEKVNMYCEACRRPVCHLCKLGGSHANHRVTSMSSA 43

B-box-type 2 zinc finger found in B box and SPRY domain-containing protein (BSPRY) and similar proteins; BSPRY is a regulatory protein for maintaining calcium homeostasis. It may regulate epithelial calcium transport by inhibiting TRPV5 activity. BSPRY is composed of a B-box, an alpha-helical coiled coil and a SPRY domain. The B-box motif 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.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....
gi 1935598078 442 PQCPRHMKQVQLlFCEDHREPICLICRLSQEHQGHRVRPIEEAA 485
Cdd:cd19834     1 DLCPDHELELDW-FCSTERRLVCAQCASLGTCRGHRVTPLEERA 43

B-box-type 2 zinc finger found in tripartite motif-containing protein 46 (TRIM46) and similar proteins; TRIM46, also known as gene Y protein (GeneY) or tripartite, fibronectin type-III and C-terminal SPRY motif protein (TRIFIC), is a microtubule-associated protein that specifically localizes to the proximal axon, partly overlaps with the axon initial segment (AIS) at later stages, and organizes uniform microtubule orientation in axons. It controls neuronal polarity and axon specification by driving the formation of parallel microtubule arrays. TRIM46 belongs to the C-I subclass of TRIM (tripartite motif) family of proteins, which 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        40
                  ....*....|....*....|....*....|....*....|.
gi 1935598078 444 CPRHMKQVQLlFCEDHREPICLICRLSQEHQGHRVRPIEEA 484
Cdd:cd19786     5 CPEHKEEVTH-YCKTCQRLVCQLCRVRRTHAGHKITPVLSA 44

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.

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gi 1935598078 444 CPRHMKQVQLlFCEDHREPICLICRLSQEHQGHRVRPI 481
Cdd:cd19787     3 CPHHHNPLSL-FCEKDQEVICGLCGLIGSHRQHKITPV 39

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 1935598078 444 CPRHMKQVQLLFCEDHREPICLICRLSQEHQGHRVRPI 481
Cdd:cd00021     2 CQEHDEEKANKYCVTCEVLYCALCKKSGAHPDHEVAPL 39