Apoptosis Flashcards
Apoptosis
It is a carefully co-ordinated collapse of cell, protein degradation, DNA fragmentation followed by rapid engulfment of corpses by neighboring cells.
It helps to shape organs and limbs during embryonic development
Necrosis
A form of cell death characterized by ATP and NAD+ that is a disorganized process
why is apoptosis needed?
Proper development
-Formation of fingers and toes of fetus
-Reabsorption of tadpole tail
Destroy cells
-Cells infected with virus
-Immune system cells
-Cells with DNA damage
-Cancer cells
Necrisus vs Apoptosis
cellular swelling vs cellular condensation
membranes are broken vs membranes intact
ATP is depleted vs requiring of ATP
Cell lyses which elicits an inflammatory response vs cell is phagocytosed so no tissue reaction
DNA fragmentation is random vs ladder-like DNA fragmentation
In vivo, whole areas are affected vs individual cells appear infected
Morphological events of apoptosis
-cell shrinkage
-organelle reduction
-mitochondrail leakage
-chromatin codensation
-nuclear fragmentation
-membrane blebbing
Membrane blebbing
It is when intact pieces of the cell separate for recognition and phagocytosis by macrophages
Extrinsic pathway of apoptosis
Death ligands
death receptors
iniatir caspace 8 ( mediates outside signal)
effector 3 caspace
PCD
(this process occurs outside cell)
Intrinsic pathway
DNA damage and p53
Mitochondria/cytochrome C (activate caspase 9)
Initiator Caspase 9
effector caspase 3
PCD
(This occurs within the cell)
MTT assay (basic)
It checks if mitochondria are metabolically active and therefore if cell is viable
MOMP assay
Mitochondrial Outer membrane potential
-checks if mitochondria are responsile for apoptosis by measuring change in membrane potential
Caspase assay
Measures the activity of enzymes (Caspase 3/7) involved in cell death
-Used to check if apoptosis has occured
Western blotting
Measures expression of proteinns involved in apoptosis
Cell cycle assay
If apoptosis is occurring then cell cycle will not happen
Apop percentage
It only binds to cells undergoing apoptosis
Ps (phosphatidyl serine )translocates to outer plasma membrane leaflet
