What are the different types of apoptosis?
The two main pathways of apoptosis are extrinsic and intrinsic as well as a perforin/granzyme pathway. Each requires specific triggering signals to begin an energy-dependent cascade of molecular events.
How many apoptosis pathways are there?
two
There are two major pathways leading to apoptosis in the mammalian system: an extrinsic pathway initiated by death receptors and an intrinsic pathway that occurs through the mitochondria (Figure 1). The extrinsic pathway depends on binding of appropriate exogenous mediators to death receptors at the cell surface.
What starts the process of apoptosis?
Apoptosis can be initiated through one of two pathways. 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. Weak external signals may also activate the intrinsic pathway of apoptosis.
What is a apoptosis assay?
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.
What is caspase assay?
Description. The Caspase-Glo® 3/7 Assay(a,b) is a homogeneous, luminescent assay that measures caspase-3 and -7 activities. The assay provides a luminogenic caspase-3/7 substrate, which contains the tetrapeptide sequence DEVD, in a reagent optimized for caspase activity, luciferase activity and cell lysis.
What causes apoptosis?
Sudden removal of the survival signals or disassociation from neighboring cells will cause a cell to initiate apoptosis. Moreover, increased cellular stress such as exposure to high heat conditions, DNA damage caused by irradiation/chemotherapy or pathogenic infection can also lead to cell death by apoptosis.
What are G1, S G2 and M phase?
Image of the cell cycle. Interphase is composed of G1 phase (cell growth), followed by S phase (DNA synthesis), followed by G2 phase (cell growth). At the end of interphase comes the mitotic phase, which is made up of mitosis and cytokinesis and leads to the formation of two daughter cells.
What are the two mechanisms of cell death?
Two distinct morphological patterns of cell death have been recognized, termed necrosis and apoptosis. Apoptosis, or programmed cell death, occurs in both physiological and pathological conditions.
How is autophagy different from apoptosis?
Apoptosis and autophagy are important molecular processes that maintain organismal and cellular homeostasis, respectively. While apoptosis fulfills its role through dismantling damaged or unwanted cells, autophagy maintains cellular homeostasis through recycling selective intracellular organelles and molecules.