Apoptosis

apoptoticprogrammed cell deathcell deathdeathpro-apoptoticproapoptoticcell apoptosisapoptotic cell deathapoptotic cellsapoptotic pathway
Apoptosis (from Ancient Greek ἀπόπτωσις "falling off") is a form of programmed cell death that occurs in multicellular organisms.wikipedia
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Programmed cell death

cell deathcellular agingdeath
Apoptosis (from Ancient Greek ἀπόπτωσις "falling off") is a form of programmed cell death that occurs in multicellular organisms.
For example, the differentiation of fingers and toes in a developing human embryo occurs because cells between the fingers apoptose; the result is that the digits are separate.

Apoptotic DNA fragmentation

autodestruction of DNAchromosomal DNA fragmentationnuclear fragmentation
These changes include blebbing, cell shrinkage, nuclear fragmentation, chromatin condensation, chromosomal DNA fragmentation, and global mRNA decay.
Apoptotic DNA fragmentation is a key feature of apoptosis, a type of programmed cell death.

Phagocyte

phagocytesphagocytic cellsphagocytic
Unlike necrosis, apoptosis produces cell fragments called apoptotic bodies that phagocytic cells are able to engulf and remove before the contents of the cell can spill out onto surrounding cells and cause damage to them.
Phagocytes are cells that protect the body by ingesting harmful foreign particles, bacteria, and dead or dying cells.

Necrosis

necroticnecrotizingnecrotic tissue
In contrast to necrosis, which is a form of traumatic cell death that results from acute cellular injury, apoptosis is a highly regulated and controlled process that confers advantages during an organism's life cycle.
In contrast, apoptosis is a naturally occurring programmed and targeted cause of cellular death.

Intrinsic apoptosis

intrinsic pathwayextrinsic apoptotic pathwayintrinsic death pathway
In the intrinsic pathway the cell kills itself because it senses cell stress, while in the extrinsic pathway the cell kills itself because of signals from other cells.
Apoptosis is a programmed form of cell death involving the degradation of cellular constituents by a group of cysteine proteases called caspases.

Bcl-2 family

BCL-2BCL-2 protein familyBH3
Some factors like Fas receptors and caspases promote apoptosis, while some members of the Bcl-2 family of proteins inhibit apoptosis.
The Bcl-2 family is most notable for their regulation of apoptosis, a form of programmed cell death, at the mitochondrion.

Cancer

cancersmalignanciescancerous
Excessive apoptosis causes atrophy, whereas an insufficient amount results in uncontrolled cell proliferation, such as cancer.
Insulin-like growth factors and their binding proteins play a key role in cancer cell proliferation, differentiation and apoptosis, suggesting possible involvement in carcinogenesis.

Bleb (cell biology)

blebbingblebblebs
These changes include blebbing, cell shrinkage, nuclear fragmentation, chromatin condensation, chromosomal DNA fragmentation, and global mRNA decay.
Most commonly, blebs are seen in apoptosis (programmed cell death) but are also seen in other non-apoptotic functions.

Atrophy

atrophicatrophiedatrophies
Excessive apoptosis causes atrophy, whereas an insufficient amount results in uncontrolled cell proliferation, such as cancer.
Causes of atrophy include mutations (which can destroy the gene to build up the organ), poor nourishment, poor circulation, loss of hormonal support, loss of nerve supply to the target organ, excessive amount of apoptosis of cells, and disuse or lack of exercise or disease intrinsic to the tissue itself.

Fas receptor

FasCD95TNFRSF6
Some factors like Fas receptors and caspases promote apoptosis, while some members of the Bcl-2 family of proteins inhibit apoptosis.
The Fas receptor is a death receptor on the surface of cells that leads to programmed cell death (apoptosis).

John Kerr (pathologist)

John KerrDr John Foxton Ross KerrJohn F. R. Kerr
While studying tissues using electron microscopy, John Foxton Ross Kerr at the University of Queensland was able to distinguish apoptosis from traumatic cell death.
He was the first to describe the ultrastructural changes in apoptosis, and could show that they differ significantly from the changes that occur in necrosis, another form of programmed cell death.

Mitochondrion

mitochondriamitochondrialmitochondrial membrane
The two best-understood activation mechanisms are the intrinsic pathway (also called the mitochondrial pathway) and the extrinsic pathway.
In addition to supplying cellular energy, mitochondria are involved in other tasks, such as signaling, cellular differentiation, and cell death, as well as maintaining control of the cell cycle and cell growth.

Pyknosis

pyknoticKaryopyknosispyknotic nuclei
These changes include blebbing, cell shrinkage, nuclear fragmentation, chromatin condensation, chromosomal DNA fragmentation, and global mRNA decay.
Pyknosis, or karyopyknosis, is the irreversible condensation of chromatin in the nucleus of a cell undergoing necrosis or apoptosis.

Death-inducing signaling complex

death-inducing signaling complex (DISC)Fas pathway
The extrinsic pathway is activated by extracellular ligands binding to cell-surface death receptors, which leads to the formation of the death-inducing signaling complex (DISC).
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.

Apoptosome

Once cytochrome c is released it binds with Apoptotic protease activating factor – 1 (Apaf-1) and ATP, which then bind to pro-caspase-9 to create a protein complex known as an apoptosome.
The apoptosome is a large quaternary protein structure formed in the process of apoptosis.

Bcl-2-associated X protein

BaxBcL-2 like proteinBcl2-associated X protein
During apoptosis, cytochrome c is released from mitochondria through the actions of the proteins Bax and Bak.
The BAX gene was the first identified pro-apoptotic member of the Bcl-2 protein family.

Andrew Wyllie

Andrew H. WyllieAndrew Hamilton Wyllie
Following the publication of a paper describing the phenomenon, Kerr was invited to join Alastair R. Currie, as well as Andrew Wyllie, who was Currie's graduate student, at University of Aberdeen.
He and his colleagues John Kerr and Alastair Currie called this process apoptosis, from the use of this word in an ancient Greek poem to mean "falling off" (like leaves falling from a tree).

H. Robert Horvitz

Robert HorvitzBob HorvitzHoward Robert Horvitz
He shared the prize with Boston biologist H. Robert Horvitz.
elegans'' to investigate whether there was a genetic program controlling cell death, or apoptosis.

Karl Vogt

Carl VogtVogtC. C. Vogt
German scientist Karl Vogt was first to describe the principle of apoptosis in 1842.
In 1842, during his time with Louis Agassiz in Neuchâtel, he discovered the mechanism of apoptosis, the programmed cell death, while studying the development of the tadpole of the midwife toad (Alytes obstetricans).

Caspase-9

caspase 9CASP99
The apoptosome cleaves the pro-caspase to its active form of caspase-9, which in turn activates the effector caspase-3.
Caspase-9 belongs to a family of caspases, cysteine-aspartic proteases involved in apoptosis and cytokine signalling.

Tumor necrosis factor alpha

TNF-αTNF-alphaTNFα
Two theories of the direct initiation of apoptotic mechanisms in mammals have been suggested: the TNF-induced (tumor necrosis factor) model and the Fas-Fas ligand-mediated model, both involving receptors of the TNF receptor (TNFR) family coupled to extrinsic signals.
TNF, being an endogenous pyrogen, is able to induce fever, apoptotic cell death, cachexia, inflammation and to inhibit tumorigenesis and viral replication and respond to sepsis via IL1- & IL6-producing cells.

Cellular Inhibitor of Apoptosis Protein 1

cIAP1
cIAP1/2 can inhibit TNF-α signaling by binding to TRAF2.
cIAP1 (also named BIRC2) is the abbreviation for a human protein, cellular inhibitor of apoptosis protein-1.

FADD

FADD-DNFAS-associating death domain-containing protein
The binding of TNF-alpha to TNFR1 has been shown to initiate the pathway that leads to caspase activation via the intermediate membrane proteins TNF receptor-associated death domain (TRADD) and Fas-associated death domain protein (FADD).
FADD is an adaptor protein that bridges members of the tumor necrosis factor receptor superfamily, such as the Fas-receptor, to procaspases 8 and 10 to form the death-inducing signaling complex (DISC) during apoptosis.

Protease

proteasespeptidaseproteinase
Both pathways induce cell death by activating caspases, which are proteases, or enzymes that degrade proteins.
These enzymes are involved in a multitude of physiological reactions from simple digestion of food proteins to highly regulated cascades (e.g., the blood-clotting cascade, the complement system, apoptosis pathways, and the invertebrate prophenoloxidase-activating cascade).

Bcl-2 homologous antagonist killer

BakBAK1
During apoptosis, cytochrome c is released from mitochondria through the actions of the proteins Bax and Bak.
This protein localizes to mitochondria, and functions to induce apoptosis.