Which caspases are involved in apoptosis?

Initiator caspases initiate the apoptosis signal while the executioner caspases carry out the mass proteolysis that leads to apoptosis. Inflammatory caspases do not function in apoptosis but are rather involved in inflammatory cytokine signaling and other types of cell death such as pyroptosis.

Is caspase-3 Required for apoptosis?

Caspases are crucial mediators of programmed cell death (apoptosis). Caspase-3 is also required for some typical hallmarks of apoptosis, and is indispensable for apoptotic chromatin condensation and DNA fragmentation in all cell types examined.

How does caspase-7 cause apoptosis?

Caspase-7 is a member of the caspase (cysteine aspartate protease) family of proteins, and has been shown to be an executioner protein of apoptosis. Sequential activation of caspases plays a central role in the execution-phase of cell apoptosis. It is activated upon cell death stimuli and induces apoptosis.

How does caspase-3 induced apoptosis?

Caspase-3 is known as an executioner caspase in apoptosis because of its role in coordinating the destruction of cellular structures such as DNA fragmentation or degradation of cytoskeletal proteins (1). The activity of caspase-3 is tightly regulated and it is produced as zymogen in an inactive pro-form (1).

What are some examples of apoptosis?

Examples: The resorption of the tadpole tail at the time of its metamorphosis into a frog occurs by apoptosis. The formation of the fingers and toes of the fetus requires the removal, by apoptosis, of the tissue between them.

What is Blebbing in apoptosis?

Blebbing is one of the defined features of apoptosis. During apoptosis (programmed cell death), the cell’s cytoskeleton breaks up and causes the membrane to bulge outward. These bulges may separate from the cell, taking a portion of cytoplasm with them, to become known as apoptotic blebs.

What is the difference between necrosis and apoptosis?

Apoptosis is described as an active, programmed process of autonomous cellular dismantling that avoids eliciting inflammation. Necrosis has been characterized as passive, accidental cell death resulting from environmental perturbations with uncontrolled release of inflammatory cellular contents.

What is the apoptosis pathway?

The intrinsic and extrinsic pathways of apoptosis are both naturally occurring processes by which a cell is directed to programmed cell death. Both pathways of apoptosis activate cell signaling cascades that are an indispensable part of the development and function of an organism.

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 caspases in apoptosis?

In death receptor-mediated apoptosis, engagement of death receptors leads to the formation of the death-inducing signaling complex (DISC) containing the death receptors, adaptor proteins, caspase-8 and caspase-10.

What are the prodomains of an initiator caspase?

Initiator caspases contain long prodomains (>90 amino acids) that allow them to interact with specific signaling complexes (see Section 2.28.2.2) and initiate the execution phase of apoptosis in response to specific death stimuli.

How does caspase 1 lead to pyroptosis in GSDMD-sufficient cells?

Chemical dimerization of caspase-1 induces pyroptosis in GSDMD-sufficient cells, but apoptosis in GSDMD-deficient cells. Caspase-1-induced apoptosis involves the Bid-caspase-9-caspase-3 axis, which can be followed by GSDME-dependent secondary necrosis/pyroptosis.

How many types of caspases are there in the body?

There are mainly fourteen types of caspases but out of them only ten caspasese have got essential role in controlling the process of apoptosis. These ten caspases have been categorized into either initiator caspases (caspase 2, 8, 9, 10) or executioner caspases (caspase 3, 6, 7).