Apoptose: Morte Programada das Células

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Apoptosis 1
🔬
Apoptosis
Class Patologia
Created
Reviewed
Programmed cell death
Biochemical signature → phosphatidylserine flipped to the outside of the 
plasma membrane
Doesn't induce inflammation (necrosis)
💡 Important in human development, physiological maintenance
The cytoplasm and the chromatin condenses, the nucleus becomes 
misshapen, cell fragments into blebs. 
The phosphatidylserine acts as a biochemical signal accumulating on the 
extracellular membrane
Extrinsic pathway - shorter
Fas ligand (trimeric) binds on Fas death receptor from another cell
The intracellular domain of Fas receptor recruits and activates FADD Fas 
associated death domain)
FADD recruits procaspases
This complex formation activates procaspases → caspases
Caspase activation leads to apoptosis
Intrinsic pathway - B's proteins family 
Apoptotic stimulus such as UV light, chemotherapy etc activates BH3-only 
protein
Jan 9, 2021 108 PM
Apoptosis 2
BH3-only blocks activity of Bcl-2 protein (anti-apoptotic)
Without Bcl-2, BH123 proteins are able to oligomerize and cytochrome C is 
release from the intermembrane of mitochondria
Cytochrome C activates the Apaf1 proteins which form a heptameric 
complex
Apaf1 recruits caspase-9 executioner caspase
Executioner caspase activation leads to apoptosis