How is intrinsic apoptosis measured?
How is intrinsic apoptosis measured?
To measure intrinsic apoptosis you can measure the activity of Bax and/or Bak by conformation specific antibody (e.g. clone6a7) using FACS. These proteins might also be activated if you add the FAS ligand because tBiD is probably also generated.
Is p53 intrinsic or extrinsic?
All these facts come to stress the important role of p53 protein in intrinsic apoptotic pathway. The p53 protein also activates the “death” receptors (belonging to the TNF-R family) and directly caspase 8 – both components of extrinsic apoptotic pathway.
What is the intrinsic cell death pathway?
The intrinsic apoptosis pathway is initiated by, for example, chemotherapy and/or radiotherapy. It is activated by a range of exogenous and endogenous stimuli, such as DNA damage, ischemia, and oxidative stress. Moreover, it plays an important function in development and in the elimination of damaged cells.
Which are the intrinsic factors involved in apoptosis?
Intrinsic pathway of apoptosis Intrinsic stresses such as oncogenes, direct DNA damage, hypoxia, and survival factor deprivation, can activate the intrinsic apoptotic pathway. p53 is a sensor of cellular stress and is a critical activator of the intrinsic pathway (See the p53 Pathway for Apoptosis Signaling).
What is cell death assay?
Cell viability and cytotoxicity assays measure cellular or metabolic changes associated with viable or nonviable cells. These assays can detect structural changes such as loss of membrane integrity upon cell death or physiological and biochemical activities indicative of living cells.
What are apoptosis assays?
An apoptosis assay detects and quantifies the cellular events associated with programmed cell death, including caspase activation, cell surface exposure of phosphatidylserine (PS) and DNA fragmentation.
How does p53 induce cell death?
P53 induces apoptosis in nontransformed cells mostly by direct transcriptional activation of the pro-apoptotic BH3-only proteins PUMA and (to a lesser extent) NOXA. Combined loss of the p53 effectors of apoptosis (PUMA plus NOXA) and cell cycle arrest/cell senescence (p21) does not cause spontaneous tumour development.
What is the function of p53?
A gene that makes a protein that is found inside the nucleus of cells and plays a key role in controlling cell division and cell death. Mutations (changes) in the p53 gene may cause cancer cells to grow and spread in the body.
What is killed by extrinsic apoptosis pathway?
Extrinsic apoptosis pathway is one of the signal pathways which may trigger the process of programmed cell death namely cell apoptosis. Apoptosis is known as a physiological process of cell deletion and is also a process of programmed cell death, resulting in morphological change and DNA fragmentation.
How does cell death occur?
Necrosis: occurs when a cell dies due to lack of a blood supply, or due to a toxin. The cells’ contents can leak out and damage neighbouring cells, and may also trigger inflammation. However, like apoptosis, necroptosis is a programmed suicide process triggered by specific proteins in the dying cell.
What is difference between extrinsic and intrinsic apoptosis?
The extrinsic pathway of apoptosis begins outside a cell, when conditions in the extracellular environment determine that a cell must die. The intrinsic pathway of apoptosis pathway begins when an injury occurs within the cell and the resulting stress activates the apoptotic pathway.
What is necrosis cell death?
Necrosis has been defined as a type of cell death that lacks the features of apoptosis and autophagy, and is usually considered to be uncontrolled. Recent research suggests, however, that its occurrence and course might be tightly regulated.
What is the intrinsic pathway of cell death?
The intrinsic cell death pathway is governed by the Bcl-2 family of proteins, which regulate commitment to cell death through the mitochondria. The key step in the intrinsic cell death pathway is the permeabilization of the mitochondrial outer membrane, after which cells are committed to cell death.
How does caspase 9 activate the extrinsic cell death pathway?
Caspase 9 then activates caspases 3 and 7, leading to apoptosis. Activation of the extrinsic cell death pathway occurs following the binding on the cell surface of “death receptors” to their corresponding ligands such as Fas, TNFR1, or TRAIL.
How does the intrinsic apoptosis pathway work?
The intrinsic apoptosis pathway begins when an injury occurs within the cell. Intrinsic stresses such as oncogenes, direct DNA damage, hypoxia, and survival factor deprivation, can activate the intrinsic apoptotic pathway. p53 is a sensor of cellular stress and is a critical activator of the intrinsic pathway.
Why do some cells have a default death pathway?
Some cells express Fas or TNF receptors that can lead to apoptosis via ligand binding and protein cross-linking. Other cells have a default death pathway that must be blocked by a survival factor such as a hormone or growth factor.