Tumor necrosis factor receptor superfamily (TNFRSF); Members of TNFR superfamily (TNFRSF) interactions with TNF superfamily (TNFSF) ligands (TNFL) control key cellular processes such as differentiation, proliferation, apoptosis, and cell growth. Dysregulation of these pathways has been shown to result in a wide range of pathological conditions, including autoimmune diseases, inflammation, cancer, and viral infection. There are 29 very diverse family members of TNFRSF reported in humans: 22 are type I transmembrane receptors (single pass with the N terminus on extracellular side of the cell membrane) and have a clear signal peptide; the remaining 7 members are either type III transmembrane receptors (single pass with the N terminus on extracellular side of the membrane but no signal sequence; TNFR13B, TNFR13C, TNFR17, and XEDAR), or attached to the membrane via a glycosylphosphatidylinositol (GPI) linker (TNFR10C), or secreted as soluble receptors (TNFR11B and TNFR6B). All TNFRs contain relatively short cysteine-rich domains (CRDs) in the ectodomain, and are involved in interaction with the TNF homology domain (THD) of their ligands. TNFRs often have multiple CRDs (between one and six), with the most frequent configurations of three or four copies; most CRDs possess three disulfide bridges, but could have between one and four. Localized or genome-wide duplication and evolution of the TNFRSF members appear to have paralleled the emergence of the adaptive immune system; teleosts (i.e. ray-finned, bony fish), which possess an immune system with B and T cells, possess primary and secondary lymphoid organs, and are capable of adaptive responses to pathogens also display several characteristics that are different from the mammalian immune system, making teleost TNFSF orthologs and paralogs of interest to better understand immune system evolution and the immunological pathways elicited to pathogens.

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gi 767971532  34 CSLARHfLEPGLLVRNCTITANAECACRNGWQCRDKECTECDPLP 78
Cdd:cd13408   78 CESCRH-CNSGLLIRNCTITANTECACPKGWQCRDKECTECDPLP 121

Tumor necrosis factor receptor superfamily member 7 (TNFRSF7), also known as CD27; TNFRSF7 (also known as CD27, T14, S152, Tp55, S152, LPFS2) has a key role in the generation of immunological memory via effects on T-cell expansion and survival, and B cell development. It binds to ligand CD70, and plays a key role in regulating B-cell activation and immunoglobulin synthesis. CD27 transduces signals that lead to the activation of NF-kappaB and MAPK8/JNK, and mediates the signaling process through adaptor proteins TRAF2 and TRAF5. CD27-binding protein (SIVA), a pro-apoptotic protein, can bind to CD27 and may play an important role in the apoptosis induced by this receptor. The potential role of the CD27/CD70 pathway in the course of inflammatory diseases, such as arthritis, and inflammatory bowel disease, suggests that CD70 may be a target for immune intervention. The expression of CD27 and CD44 molecules correlates with the differentiation stage of B cell precursors and has been shown to have a biological significance in acute lymphoblastic leukemia.

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gi 767971532  34 CSLARHfLEPGLLVRNCTITANAECACRNGWQCRDKECTECDPLP 78
Cdd:cd13408   78 CESCRH-CNSGLLIRNCTITANTECACPKGWQCRDKECTECDPLP 121

Tumor necrosis factor receptor superfamily member 7 (TNFRSF7), also known as CD27; TNFRSF7 (also known as CD27, T14, S152, Tp55, S152, LPFS2) has a key role in the generation of immunological memory via effects on T-cell expansion and survival, and B cell development. It binds to ligand CD70, and plays a key role in regulating B-cell activation and immunoglobulin synthesis. CD27 transduces signals that lead to the activation of NF-kappaB and MAPK8/JNK, and mediates the signaling process through adaptor proteins TRAF2 and TRAF5. CD27-binding protein (SIVA), a pro-apoptotic protein, can bind to CD27 and may play an important role in the apoptosis induced by this receptor. The potential role of the CD27/CD70 pathway in the course of inflammatory diseases, such as arthritis, and inflammatory bowel disease, suggests that CD70 may be a target for immune intervention. The expression of CD27 and CD44 molecules correlates with the differentiation stage of B cell precursors and has been shown to have a biological significance in acute lymphoblastic leukemia.

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gi 767971532  34 CSLARHfLEPGLLVRNCTITANAECACRNGWQCRDKECTECDPLP 78
Cdd:cd13408   78 CESCRH-CNSGLLIRNCTITANTECACPKGWQCRDKECTECDPLP 121

Tumor necrosis factor receptor superfamily member 1B (TNFRSF1B) in teleost; also known as TNFR2; This subfamily of TNFRSF1B (also known as TNFR2, type 2 TNFR, TNFBR, TNFR80, TNF-R75, TNF-R-II, p75, CD120b) is found in teleosts. It binds TNF-alpha, but lacks the death domain (DD) that is associated with the cytoplasmic domain of TNFRSF1A (TNFR1). It is inducible and expressed exclusively by oligodendrocytes, astrocytes, T cells, thymocytes, myocytes, endothelial cells, and in human mesenchymal stem cells. TNFRSF1B protects oligodendrocyte progenitor cells (OLGs) against oxidative stress, and induces the up-regulation of cell survival genes. While pro-inflammatory and pathogen-clearing activities of TNF are mediated mainly through activation of TNFRSF1A, a strong activator of NF-kappaB, TNFRSF1B is more responsible for suppression of inflammation. Although the affinities of both receptors for soluble TNF are similar, TNFRSF1B is sometimes more abundantly expressed and thought to associate with TNF, thereby increasing its concentration near TNFRSF1A receptors, and making TNF available to activate TNFRSF1A (a ligand-passing mechanism). Knockout studies in zebrafish embryos have shown that a signaling balance between TNFRSF1A and TNFRSF1B is required for endothelial cell integrity. TNFRSF1A signals apoptosis through caspase-8, whereas TNFRSF1B signals survival via NF-kB in endothelial cells. In goldfish (Carassius aurutus L.), TNFRSF1B expression is substantially higher than that of TNFRSF1 in tissues and various immune cell types. Both receptors are most robustly expressed in monocytes; mRNA levels of TNFRSF1B are lowest in peripheral blood leukocytes.

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gi 767971532  47 VRNCTITANAECACRNGWQC----RDKECTEC 74
Cdd:cd15835   75 AQNCSSTTNAVCVCKPGMYCimgfDHPSCSEC 106

Tumor necrosis factor receptor superfamily member 6 (TNFRSF6), also known as fas cell surface death receptor (Fas); TNFRSF6 (also known as fas cell surface death receptor (FasR) or Fas, APT1, CD95, FAS1, APO-1, FASTM, ALPS1A) contains a death domain and plays a central role in the physiological regulation of programmed cell death. It has been implicated in the pathogenesis of various malignancies and diseases of the immune system. The receptor interactions with the Fas ligand (FasL), allowing the formation of a death-inducing signaling complex that includes Fas-associated death domain protein (FADD), caspase 8, and caspase 10; autoproteolytic processing of the caspases in the complex triggers a downstream caspase cascade, leading to apoptosis. This receptor has also been shown to activate NF-kappaB, MAPK3/ERK1, and MAPK8/JNK, and is involved in transducing the proliferating signals in normal diploid fibroblast and T cells. Of the several alternatively spliced transcript variants, some are candidates for nonsense-mediated mRNA decay (NMD). Isoforms lacking the transmembrane domain may negatively regulate the apoptosis mediated by the full length isoform.

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gi 767971532  42 EPGLLV-RNCTITANAECACRNGWQCRDKECTECDP 76
Cdd:cd10579   72 EHGLEVeKNCTRTQNTKCRCKSNFFCNSSPCEHCDP 107