Fas receptor

FAS
Gene ontology
Molecular function	kinase binding protein binding transmembrane signaling receptor activity signal transducer activity identical protein binding tumor necrosis factor-activated receptor activity tumor necrosis factor binding calmodulin binding signaling receptor activity
Cellular component	CD95 death-inducing signaling complex membrane extracellular region cell surface extracellular exosome integral component of membrane plasma membrane integral component of plasma membrane external side of plasma membrane death-inducing signaling complex membrane raft cytosol nuclear body mitochondrion
Biological process	renal system process activation-induced cell death of T cells tumor necrosis factor-mediated signaling pathway T cell homeostasis positive regulation of extrinsic apoptotic signaling pathway in absence of ligand cellular response to mechanical stimulus circadian rhythm apoptotic signaling pathway positive regulation of extrinsic apoptotic signaling pathway regulation of extrinsic apoptotic signaling pathway via death domain receptors activation of cysteine-type endopeptidase activity involved in apoptotic process apoptotic process activation of cysteine-type endopeptidase activity involved in apoptotic signaling pathway spleen development negative thymic T cell selection regulation of lymphocyte differentiation necroptotic signaling pathway motor neuron apoptotic process inflammatory response regulation of myeloid cell differentiation protein homooligomerization response to toxic substance B cell mediated immunity neuron apoptotic process positive regulation of protein homooligomerization cellular response to lithium ion positive regulation of lymphocyte apoptotic process negative regulation of apoptotic process immune response gene expression cellular response to hyperoxia negative regulation of B cell activation response to glucocorticoid extrinsic apoptotic signaling pathway in absence of ligand inflammatory cell apoptotic process immunoglobulin production signal transduction hepatocyte apoptotic process response to lipopolysaccharide extrinsic apoptotic signaling pathway regulation of apoptotic process positive regulation of apoptotic process regulation of cell population proliferation negative regulation of extrinsic apoptotic signaling pathway via death domain receptors multicellular organism development extrinsic apoptotic signaling pathway via death domain receptors positive regulation of protein phosphorylation regulation of stress-activated MAPK cascade cellular response to amino acid starvation Fas signaling pathway positive regulation of apoptotic signaling pathway positive regulation of cysteine-type endopeptidase activity involved in apoptotic signaling pathway protein-containing complex assembly
Sources:Amigo / QuickGO

Ensembl				ENSG00000026103	ENSMUSG00000024778
UniProt	P25445	P25446
RefSeq (mRNA)	NM_000043 NM_152871 NM_152872 NM_152873 NM_152874 NM_152875 NM_152876 NM_152877 NM_001320619	NM_001146708 NM_007987
RefSeq (protein)	NP_000034 NP_001307548 NP_690610 NP_690611	NP_001140180 NP_032013
Location (UCSC)	Chr 10: 88.95 – 89.03 Mb	Chr 19: 34.29 – 34.33 Mb
PubMed search	[3]	[4]

Wikidata

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The Fas receptor, also known as Fas, FasR, apoptosis antigen 1 (APO-1 or APT),

The Fas receptor is a

Gene

FAS receptor gene is located on the long arm of

mammals

.

Protein

Previous reports have identified as many as eight splice variants, which are translated into seven

The mature Fas protein has 319 amino acids, has a predicted molecular weight of 48 kilodaltons and is divided into three domains: an

residues. The transmembrane and cytoplasmic domains have 17 and 145 amino acids respectively. Exons 1 through 5 encode the extracellular region. Exon 6 encodes the transmembrane region. Exons 7-9 encode the intracellular region.

Function

Fas forms the death-inducing signaling complex (DISC) upon ligand binding. Membrane-anchored Fas ligand trimer on the surface of an adjacent cell causes oligomerization of Fas. Recent studies which suggested the trimerization of Fas could not be validated. Other models suggested the oligomerization up to 5–7 Fas molecules in the DISC.^[11] This event is also mimicked by binding of an agonistic Fas antibody, though some evidence suggests that the apoptotic signal induced by the antibody is unreliable in the study of Fas signaling. To this end, several clever ways of trimerizing the antibody for in vitro research have been employed.

Upon ensuing death domain (DD) aggregation, the receptor complex is internalized via the cellular endosomal machinery. This allows the adaptor molecule FADD to bind the death domain of Fas through its own death domain.^[12]

FADD also contains a

into p10 and p18 subunits, two each of which form the active heterotetramer enzyme. Active caspase-8 is then released from the DISC into the cytosol, where it cleaves other effector caspases, eventually leading to DNA degradation, membrane blebbing, and other hallmarks of apoptosis.

Recently, Fas has also been shown to promote tumor growth, since during tumor progression, it is frequently downregulated or cells are rendered apoptosis resistant. Cancer cells in general, regardless of their Fas apoptosis sensitivity, depend on constitutive activity of Fas. This is stimulated by cancer-produced Fas ligand for optimal growth.^[14]

Although Fas has been shown to promote tumor growth in the above mouse models, analysis of the human cancer genomics database revealed that FAS is not significantly focally amplified across a dataset of 3131 tumors (FAS is not an

in humans.

In cultured cells, FasL induces various types of cancer cell apoptosis through the Fas receptor. In AOM-DSS-induced colon carcinoma and MCA-induced sarcoma mouse models, it has been shown that Fas acts as a tumor suppressor.

Role in apoptosis

Some reports have suggested that the extrinsic Fas pathway is sufficient to induce complete apoptosis in certain cell types through DISC assembly and subsequent caspase-8 activation. These cells are dubbed Type 1 cells and are characterized by the inability of anti-apoptotic members of the Bcl-2 family (namely Bcl-2 and Bcl-xL) to protect from Fas-mediated apoptosis. Characterized Type 1 cells include H9, CH1, SKW6.4 and SW480, all of which are lymphocyte lineages except the latter, which is a colon adenocarcinoma lineage. However, evidence for crosstalk between the extrinsic and intrinsic pathways exists in the Fas signal cascade.

In most cell types, caspase-8 catalyzes the cleavage of the pro-apoptotic BH3-only protein

proteins (IAPs).

Interactions

Fas receptor has been shown to

with:

• Caspase 8,^[22][23][24]
• Caspase 10,^[25]
• CFLAR,^[23][24]
• FADD,^{[22][23][26][27][28][29]}
• Fas ligand,^{[22][30][31][32]}
• PDCD6,^[33] and
• Small ubiquitin-related modifier 1.^[34][35]

References

Further reading

• Nagata S (February 1997). "Apoptosis by death factor". Cell. 88 (3): 355–65.
  S2CID 494841
  .
• Cascino I, Papoff G, Eramo A, Ruberti G (January 1996). "Soluble Fas/Apo-1 splicing variants and apoptosis". Frontiers in Bioscience. 1 (4): d12-8.
  PMID 9159204
  .
• Uckun FM (September 1998). "Bruton's tyrosine kinase (BTK) as a dual-function regulator of apoptosis". Biochemical Pharmacology. 56 (6): 683–91.
  PMID 9751072
  .
• Krammer PH (October 2000). "CD95's deadly mission in the immune system". Nature. 407 (6805): 789–95.
  S2CID 4328897
  .
• Siegel RM, Chan FK, Chun HJ, Lenardo MJ (December 2000). "The multifaceted role of Fas signaling in immune cell homeostasis and autoimmunity". Nature Immunology. 1 (6): 469–74.
  S2CID 345769
  .
• Yonehara S (2003). "Death receptor Fas and autoimmune disease: from the original generation to therapeutic application of agonistic anti-Fas monoclonal antibody". Cytokine & Growth Factor Reviews. 13 (4–5): 393–402.
  PMID 12220552
  .
• Choi C, Benveniste EN (January 2004). "Fas ligand/Fas system in the brain: regulator of immune and apoptotic responses". Brain Research. Brain Research Reviews. 44 (1): 65–81.
  S2CID 46587211
  .
• Poppema S, Maggio E, van den Berg A (March 2004). "Development of lymphoma in Autoimmune Lymphoproliferative Syndrome (ALPS) and its relationship to Fas gene mutations". Leukemia & Lymphoma. 45 (3): 423–31.
  S2CID 35128360
  .

External links

• FAS+Receptor at the U.S. National Library of Medicine Medical Subject Headings (MeSH)
• Overview of all the structural information available in the PDB for UniProt: P25445 (Human Tumor necrosis factor receptor superfamily member 6) at the PDBe-KB.
• Overview of all the structural information available in the PDB for UniProt: P25446 (Mouse Tumor necrosis factor receptor superfamily member 6) at the PDBe-KB.