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.

                         10        20
                 ....*....|....*....|....*..
gi 226443053  35 RRVRETDKNCSEGLYQGGPFCCQPCQP 61
Cdd:cd10579    1 RNITKREINCSEGLYRGGQFCCQPCPP 27

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.

                         10        20
                 ....*....|....*....|....*..
gi 226443053  35 RRVRETDKNCSEGLYQGGPFCCQPCQP 61
Cdd:cd10579    1 RNITKREINCSEGLYRGGQFCCQPCPP 27

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.

                         10        20
                 ....*....|....*....|....*..
gi 226443053  35 RRVRETDKNCSEGLYQGGPFCCQPCQP 61
Cdd:cd10579    1 RNITKREINCSEGLYRGGQFCCQPCPP 27