Cell Death or Apoptosis Flashcards
swell and burst, spilling their contents over their neighbors and eliciting an inflammatory response
Necrotic cells
One form of necrosis is a form of programmed cell death that is triggered by a specific regulatory signal from other cells
Necroptosis
Form of programmed cell death, Involves cell shrinkage, Loss of adhesion to other cells, Dissection of chromatin, Engulfment by phagocytosis
Mediated by caspases
Apoptosis
What species does apoptosis first found?
C. elegans
Why do we need to have Apoptosis?
Eliminates unwanted cells
Embryonic development to form structure
Eliminate abnormal, nonfunctional and dangerous cells
Master regulator for cell cycle protection
Triggering cell death
P53
functions like a proteins scissors
caspases
Example of caspases in C. elegans
CED-3
Example of Caspases in Drosophila
DronC
DrlCE
Dcp-1
Example of Caspases in Mammals
Caspase-9
Caspase-3
Caspase-7
two major classes of apoptotic caspases
Initiator caspase
Executioner caspase
major function of initiator caspases
activate the executioner caspases
One initiator caspase complex can activate many executioner caspases, resulting in an amplifying proteolytic cascade
TRUE OR FALSE
TRUE
What does executioner caspases do once activated?
catalyze the widespread protein cleavage events that kill the cell
What are two pathways for cell death?
Extrinsic Apoptotic Pathway (triggered by outside) and Intrinsic (triggered by events inside) in mammals
what happened when there is an activation of Caspase 8 or Caspase 9?
activates Executioner Caspases and triggers APOPTOSIS by cutting all proteins in dying cells
what are target proteins that are cut up when there is an Apoptosis?
Nuclear lamins (intermediate filaments); mutation here leads to aging
Protein kinases (ex. Focal adhesion kinase): cause cell detachments
Proteins of the cytoskeleton
Caspase activated DNase called CAD
-CAD startup cutting the DNA
Receptor present in extrinsic pathway that activates initiator caspase and leads to executioner caspase activation
TNF and Fas death receptor
Death receptor containing an extracellular ligand-binding domain which is required for the receptors to activate the apoptotic program
Tumor necrosis factor (TNF) receptor
Fas ligand that activate death receptors and thereby trigger the extrinsic pathway of apoptosis
TRUE OR FALSE
TRUE
Anti-apoptotic protein
Suppresses caspase-8 in DISC and caspase-10 activation
FLIP
what makes the mitochondria porous or may mga holes and the cytochrome c which is normally seen in the mitochondria will trigger initiator caspase and trigger the death of a cell
BAX and BAK
Key protein; When released into the cytosol, it binds to an adaptor protein called Apaf1 (apoptotic protease activating factor-1)
Cytochrome C
recruit initiator caspase-9 proteins, which are thought to be activated by proximity in the apoptosome, just as caspase-8 is activated in the DISC
Apaf1
proteins regulate the intrinsic pathway of apoptosis
Bcl2
suppress apoptosis when expressed in the worm Caenorhabditis elegans
Bcl2
controlling the release of cytochrome c and other intermembrane mitochondrial proteins into the cytosol
Bcl2
Three classes of Bcl2
Anti- apoptotic BCL-2 Proteins
Pro-apoptotic BCL-2 Proteins
Pro-apoptotic BH3-only protein
type of Anti-apoptotic BCL-2 proteins that bind to Bak and prevent it from oligomerization, thereby inhibiting the release of cytochrome c and other intermembrane proteins
Bcl2 and BclXL
Class of Bcl2 that inhibit apoptosis by blocking the release
Anti- apoptotic BCL-2 Proteins
promote apoptosis by enhancing the release
Pro-apoptotic BCL-2 Proteins
example of Pro-apoptotic BCL-2 Proteins
BAK and BAX : similar to Bcl2 but lack the BH4 domain
bound to the mitochondrial outer membrane even in the absence of an apoptotic signal
BAK
mainly located in the cytosol and translocate to the mitochondria only after an apoptotic signal activates it
BAX
class of Bcl2: homology with Bcl2 in only the BH3 domain and promote apoptosis mainly by inhibiting anti-apoptotic Bcl2 family
Pro-apoptotic BH3-only protein
Holes na kung saan lumabas si cytochrome c that trigger apoptosis
MOMP (Mitochondrial outer membrane permeability pore )
ALSO REGULATE APOPTOSIS THAT HELPS CONTROL CASPASES
INHIBITOR OF APOPTOSIS PROTEINS (IAP) AND ANTI-IAP PROTEINS
Function of caspases
cuts proteins that leads to apoptosis
bind to IAPs to prevent their binding to caspases
Anti- IAP proteins
Nerve cells that receive enough survival signals live, while the others die
TRUE OR FALSE
TRUE
______ inhibits apoptosis
survival factor such as anti- apoptotic Bcl2
the apoptotic cell and its fragments do not break open and release their contents, but instead remain intact as they are efficiently eaten.. this process is called ____
phagocytosed
Either Excessive or Insufficient Apoptosis Can Contribute to Disease
TRUE OR FALSE
TRUE
