What pathways are activated in response to an apoptotic signal?
It is generally accepted that there are two major pathways of apoptotic cell death induction: extrinsic signaling through death receptors that leads to the formation of the death-inducing signaling complex (DISC), and intrinsic signaling mainly through mitochondria which leads to the formation of the apoptosome.
What is the signal for apoptosis to begin?
Apoptosis is triggered when cell-surface death receptors such as Fas are bound by their ligands (the extrinsic pathway) or when Bcl2-family proapoptotic proteins cause the permeabilization of the mitochondrial outer membrane (the intrinsic pathway).
What activates the extrinsic apoptotic pathway?
The extrinsic pathway that initiates apoptosis is triggered by a death ligand binding to a death receptor, such as TNF-α to TNFR1. This death domain plays a critical role in transmitting the death signal from the cell surface to the intracellular signaling pathways.
Where do apoptotic signals come from?
Signaling for apoptosis occurs through multiple independent pathways that are initiated either from triggering events within the cell or from outside the cell, for instance, by ligation of death receptors.
Is apoptosis autocrine signaling?
Autocrine regulation of apoptosis was demonstrated by increased FasL activity after stimulation of GFP− cells with anti-CD3, phorbyl myristyl acetate plus ionomycin, or Con A. Paracrine regulation of apoptosis was suggested by the induction of apoptosis of GFP− cells after coculture with unstimulated GFP+ cells.
What are anti apoptotic genes?
FLIP (FLICE-inhibitory protein), anti-apoptotic members of the Bcl2 family and inhibitors of apoptosis (IAP) are the main three groups of anti-apoptotic genes that counteract caspase activation through both the extrinsic and intrinsic apoptotic pathways.
What is CD95 ligand?
The CD95 ligand (CD95L, Apo-1L, FasL, CD178) is a 281-amino-acid-containing type II transmembrane protein of the TNF family of death factors (Figure 1). 1. Its death-inducing function is best documented in the context of activation-induced cell death (AICD) in T cells.
Where do apoptotic signal come from?
Which of the following is an anti apoptotic protein?
Which of the following is an anti apoptotic protein? Explanation: Bcl-Xs is a Bcl-2 family protein which is pro-apototic, also bim and NOXA are proapoptotic factors. Bfl 1 is an anti apoptotic member of Bcl- 2 family.