What is FADD apoptosis?

FAS-associated death domain protein (FADD) is a 23 kDa adaptor protein involved in initiating apoptosis. Activated FADD recruits apoptotic pro-caspases to form the death-inducing signal complex (DISC). Formation of the DISC allows cleavage and activation of initiator caspases-8 and -10.

What is the meaning of FADD?

FADD

Do T cells express FAS or FasL?

In particular, FasL is expressed by astrocytes, oligodendrocytes, and macrophages, while Fas is mainly expressed by macrophages, T cells, and oligodendrocytes (69, 70). Several studies have addressed the role of the Fas–FasL system in experimental autoimmune encephalomyelitis (EAE), the murine model of MS (71–75).

What is the function of caspases?

Caspases (cysteine-aspartic proteases) are proteolytic enzymes largely known for their role in controlling cell death and inflammation.

What is disc apoptosis?

The death-inducing signaling complex or DISC is a multi-protein complex formed by members of the “death receptor” family of apoptosis-inducing cellular receptors. It transduces a downstream signal cascade resulting in apoptosis.

What causes Pyroptosis?

Pyroptosis can take place in immune cells and is also reported to occur in keratinocytes and some epithelial cells. The process is initiated by formation of a large supramolecular complex termed the inflammasome (also known as a pyroptosome) upon intracellular danger signals.

What does FAS stand for in apoptosis?

FAS (Fas cell surface death receptor)

What is the relationship between B and T cells?

T cells are responsible for cell-mediated immunity. B cells, which mature in the bone marrow, are responsible for antibody-mediated immunity. The cell-mediated response begins when a pathogen is engulfed by an antigen-presenting cell, in this case, a macrophage.

Do caspases cleave DNA?

1. Regulation of DNA fragmentation by phosphorylation of the MAPK family and mitochondrial proteins. Cleaved caspase-3 translocates to the nucleus, where it cleaves substrates such as the DNA repair enzyme PARP and ICAD. Cleavage of ICAD results in the release and activation of CAD, which induces DNA fragmentation.

What is the function of caspase-3?

Caspases are crucial mediators of programmed cell death (apoptosis). Among them, caspase-3 is a frequently activated death protease, catalyzing the specific cleavage of many key cellular proteins.

What is the main function of disc in apoptosis?

The DISC is composed of the death receptor, FADD, and caspase 8. It transduces a downstream signal cascade resulting in apoptosis.

What cascade is activated in apoptosis?

Caspase Cascade Caspases
Caspases are a family of cysteine proteases that act in concert in a cascade triggered by apoptosis signaling. The culmination of this cascade is the cleavage of a number of proteins in the cell, followed by cell disassembly, cell death, and, ultimately, the phagocytosis and removal of the cell debris.

What is the role of the Fas signaling pathway?

The Fas cell signaling pathway has a central role in the physiological regulation of programmed cell death (also called apoptosis) and has been implicated in the pathogenesis of various malignancies and diseases of the immune system.

How is FADD related to the death effector domain?

FADD carries a DED (Death Effector Domain) and by homologous interaction, it recruits the DED containing Procaspase-8 protein which is in inactive state. This protein complex is also known as DISC (Death-Inducing Signaling Pathways) and exists in Type-I cells.

How does FasL-induced clustering of FAS and FADD occur?

FasL-induced clustering of Fas, FADD, and caspase-8 or -10 within the DISC results in autoproteolytic processing of these caspases by induced proximity and in release of the processed active proteases ( Fig. 1 ).

How does the Fas receptor lead to apoptosis?

The Fas receptor, upon binding to the FasL, trimerizes and induces apoptosis through a cytoplasmic domain called DD (Death Domain) that interacts with signaling adaptors like FAF-1 (Fas-Associated Factor-1), FADD (Fas-Associated Death Domain), Daxx, FAP-1, FLASH (FLICE-associated huge), and RIP (Receptor-Interacting Protein).