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 2217269425  61 SGVKTHCPPCNPGFF--KTNNSTCQPCPYGSYSNGSD----CT-------RCPAGTEPAVGF 109
Cdd:cd13406    30 GTQDTVCSPCEPGFYneAVNYEPCKPCTQCNQRSGSEekqkCTktsdtvcRCRPGTQPLDSY 91

Tumor necrosis factor receptor superfamily member 4 (TNFRSF4), also known as CD134 or OXO40; TNFRSF4 (also known as OX40, ACT35, CD134, IMD16, TXGP1L) activates NF-kappaB through its interaction with adaptor proteins TRAF2 and TRAF5. It also promotes the expression of apoptosis inhibitors BCL2 and BCL2lL1/BCL2-XL, and thus suppresses apoptosis. It is primarily expressed on activated CD4+ and CD8+ T cells, where it is transiently expressed and upregulated on the most recently antigen-activated T cells within inflammatory lesions. This makes it an attractive target to modulate immune responses, i.e. TNFRSF4 (OX40) blocking agents to inhibit adverse inflammation or agonists to enhance immune responses. An artificially created biologic fusion protein, OX40-immunoglobulin (OX40-Ig), prevents OX40 from reaching the T-cell receptors, thus reducing the T-cell response. Some single nucleotide polymorphisms (SNPs) of its natural ligand OX40 ligand (OX40L, CD252), which is also found on activated T cells, have been associated with systemic lupus erythematosus.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 2217269425  61 SGVKTHCPPCNPGFF--KTNNSTCQPCPYGSYSNGSD----CT-------RCPAGTEPAVGF 109
Cdd:cd13406    30 GTQDTVCSPCEPGFYneAVNYEPCKPCTQCNQRSGSEekqkCTktsdtvcRCRPGTQPLDSY 91

Tumor necrosis factor receptor superfamily member 4 (TNFRSF4), also known as CD134 or OXO40; TNFRSF4 (also known as OX40, ACT35, CD134, IMD16, TXGP1L) activates NF-kappaB through its interaction with adaptor proteins TRAF2 and TRAF5. It also promotes the expression of apoptosis inhibitors BCL2 and BCL2lL1/BCL2-XL, and thus suppresses apoptosis. It is primarily expressed on activated CD4+ and CD8+ T cells, where it is transiently expressed and upregulated on the most recently antigen-activated T cells within inflammatory lesions. This makes it an attractive target to modulate immune responses, i.e. TNFRSF4 (OX40) blocking agents to inhibit adverse inflammation or agonists to enhance immune responses. An artificially created biologic fusion protein, OX40-immunoglobulin (OX40-Ig), prevents OX40 from reaching the T-cell receptors, thus reducing the T-cell response. Some single nucleotide polymorphisms (SNPs) of its natural ligand OX40 ligand (OX40L, CD252), which is also found on activated T cells, have been associated with systemic lupus erythematosus.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 2217269425  61 SGVKTHCPPCNPGFF--KTNNSTCQPCPYGSYSNGSD----CT-------RCPAGTEPAVGF 109
Cdd:cd13406    30 GTQDTVCSPCEPGFYneAVNYEPCKPCTQCNQRSGSEekqkCTktsdtvcRCRPGTQPLDSY 91