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Current concepts in apoptosis: The physiological suicide program revisited
Cellular & Molecular Biology Letters volume 11, pages506–525(2006)
Apoptosis, or programmed cell death (PCD), involves a complex network of biochemical pathways that normally ensure a homeostatic balance between cellular proliferation and turnover in nearly all tissues. Apoptosis is essential for the body, as its deregulation can lead to several diseases. It plays a major role in a variety of physiological events, including embryonic development, tissue renewal, hormone-induced tissue atrophy, removal of inflammatory cells, and the evolution of granulation tissue into scar tissue. It also has an essential role in wound repair. The various cellular and biochemical mechanisms involved in apoptosis are not fully understood. However, there are two major pathways, the extrinsic pathway (receptor-mediated apoptotic pathway) and the intrinsic pathway (mitochondria-mediated apoptotic pathway), which are both well established. The key component in both is the activation of the caspase cascade. Caspases belong to the family of proteases that ultimately, by cleaving a set of proteins, cause disassembly of the cell. Although the caspase-mediated proteolytic cascade represents a central point in the apoptotic response, its initiation is tightly regulated by a variety of other factors. Among them, Bcl-2 family proteins, TNF and p53 play pivotal roles in the regulation of caspase activation and in the regulation of apoptosis. This review summarizes the established concepts in apoptosis as a physiological cell suicide program, highlighting the recent and significant advances in its study.
apoptosis protease activating factor-1
B-cell lymphoma family
baculoviral IAP repeat
BIR repeat-containing ubiquitin-conjugating enzyme
caspase recruitment domain
cysteine-rich extracellular domain
death-inducing signaling complex
death effector domain
Fas-associated death domain protein
FADD-like-ICE-inhibitory protein or FLICE inhibitory protein
inhibitor of apoptosis
mitochondrial outer membrane permeabilization
programmed cell death
p53-up-regulated modulator of apoptosis
permeability transition pore
receptor interacting protein
TNF alpha-converting enzyme
transforming growth factor-β
tumor necrosis factor α
tumor necrosis factor receptor-1
TNF-related apoptosis-inducing ligand
TNF-receptor associated protein with death domain
terminal deoxynucleotidyl transferase-mediated (TdT-mediated) dUTP-digoxigenin nick end labeling
voltage-dependent anion channel
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Chowdhury, I., Tharakan, B. & Bhat, G.K. Current concepts in apoptosis: The physiological suicide program revisited. Cell Mol Biol Lett 11, 506–525 (2006). https://doi.org/10.2478/s11658-006-0041-3
- Programmed cell death