Cell Death Flashcards
Describe the characteristics of irreversible necrosis
increased intracellular calcium, autolysis, cell bursting
Describe the characteristics of reversible necrosis
membrane integrity compromised, organelle and cell swelling
What is necrosis
wide spread cell death
how is necrosis initiated
external stimulus
how is apoptosis initiated
internal and external stimuli
what is apoptosis
programmed cell death
What are the characteristics of apoptosis
shrinking, break down of nuclear envelope, phagocytosis
TRUE or FALSE - apoptosis doesnt require energy
FALSE
Describe the function of apoptosis in brain ischaemia
surrounding cells undergo apoptosis to restrict spread of cell death
What are the uses of apoptosis in development
digit formation, neural connection refinement
What are the ced genes
genes in c.elegans that inhibit/repress apoptosis
what do ced genes recognise
apoptotic signal
What is the function of ced3 and ced4
trigger apoptosis
what is the effect of decrease in ced3 or ced4
excess adult cells
what is the effect of decrease in ced9
massive cell death
which ced gene is related to caspases
ced3
what are caspases
executioners of cell death = essential for apoptosis
is the caspase pathway reversible or irreversible
irreversible
What does caspase stand for
c - cysteine at active site and aspartic acid at cleavage site on target proteins
What activates initiator caspase
apoptotic signals
What do initiator caspases activate
executioner caspases
What is the function of adaptor proteins
stick together initiator caspases
what is the function of active executioner caspases
cleave multiple proteins and trigger irreversible apoptosis
How many executioner caspases can one initiator caspases activate
multiple
what happens to the targets of caspases
nuclear breakdown, cytoskeletal changes, NO DNA repair
What are the components of the extrinsic apoptosis pathway
death ligands, death receptors, initiator caspase 8 and effector caspase 3
What are the components of the intrinsic pathway of apoptosis
DNA damage, mitochondria/cytochrome C, initiator caspase 9 and effector caspase 3
what can trigger the intrinsic pathway of apoptosis
stress signals, developmental signals
What are the functions of the proteins cleaved by caspases
DNA repair, cell cycle
