T1Q5: Apoptosis

Question 1

necrosis

1. wh
2. wy

Answer 1

disordered death due to cell damage

Question 2

apopotosis

Answer 2

ordered cell death

Question 3

intrinsic pathway

Answer 3

wh: orderly cell suicide
wy: withdrawal of cytokines/ growth factor or due to damage from radiation/ free radcials

Question 4

extrinsic pathway

Answer 4

wh: cell execution
wy: triggered by Fas/Fas-Ligand, used by Cytotoxic T-Cells

Question 5

Apaf-1

Answer 5

sig: adaptor protein, associates with caspases and activates instrinsic cell death
def: pro-apoptotic protease activating factor 1

Question 6

FADD

Answer 6

sig: activated Fas receptor associates with FADD as an adaptor molecule to transmit its signal inside the cell
def: fas associated protein with Death Domain

Question 7

Blc-2

Answer 7

sig: REGULATORS of the intrinsic pathway. some are pro- others anti-

def:
1. breakpoint cluster locus-2 protein, a pro-survival protein expressed on the cytoplasmic leaflet of various membrane proteins
2. a family of proteins transmembrane proteins named after their founding member that either favor or prevent cell death

Question 8

BH1-4

Answer 8

def: Bcl-2-homology, a conserved domain in Bcl-2 family of regulatory proteins.

sig:
survival regulatory factors contain BH1&2
Bcl-2 proper, Bcl-xL, and Bcl-w

pro-apoptotic:
Bax, Bac, and Bad- conain Bh1, BH2, Bh3

Question 9

BH3

Answer 9

sig. found in several KILLER proteins that may play an antagonistic role to pro survival proteins
def. break-cluster 2 homology region

Question 10

mechanism:
BCl2 anti-apoptoic proteins
(Bcl-2 proper, Bcl-xL, and Bcl-w)

Answer 10

anti-apopotic proteins bind to Apaf1 and prevent it from activating capase enzyme

They may also prevent the mitochondria from releasing cytochrome C complex

Question 11

mechanism: BCL2 family
pro-apoptotic proteins
Bax, BAD, Bak and Bok

Answer 11

removal of pro-survival proteins from Apaf1

They may also promote liberation of cytochrome C from the mitochondrion

Question 12

caspase

Answer 12

def: cysteine in active site, acts on aspartic acid residues
significance: Ced caspases activate apoptosis

Question 13

initiating caspases

Answer 13

wh: Ced8 & Ced9 begin apoptosis by associating with adaptors
hw: aggregation and association with adaptor proteins (FADD or Apaf-1)

Question 14

execution caspases

Answer 14

wh: Ced3, Ced6, Ced7 destroy things and activate things that destroy things
hw: activated by cleavage by initiating caspases and they go on to cleave substrates within the cell

Question 15

CAD

Answer 15

wh: cytoplasmic DNAse (CAD)
wy: example of a protein that is selectively/ coordinately cleaved to produce targeted loss of function rather than indiscriminate damage

Question 16

scramblase

Answer 16

flips phosphotidyl serine from its position in the inner cytoplasmic leaflet to the extracellular membrane

Question 17

phosphatidyl serine

Answer 17

wh: pholipid in Plasma membrane
wy: “eat me” signal

Question 18

CED1

Answer 18

a major receptor for phagocytosis of apoptotic cells (corpses)

Question 19

Myc

Answer 19

wh: an oncogene (protective gene that when mutated can cause cancer)
wy: may initiate apoptosis if there is an absence of growth factors or genotoxic damage

Question 20

p53

Answer 20

wh: an oncogene
wy: initiates apoptosis if cell damage occurs

Question 21

dysregulated apoptosis: inhibition

Answer 21

cancer

Question 22

dysregulated apoptosis: increased apoptosis

Answer 22

1. neurodegenerative diseases (Alzheimer’s)
2. ischemic injury: heart disease and stroke
3. virus-induced lymphocyte depletion (AIDS)

Question 23

Apaf-1 is to ___ as ____ is to Extrinsic Pathway

Answer 23

“adaptor” protein question

Apaf-1 is to the intrinsic pathway as FADD is to the Extrinsic Pathway

Question 24

What two capases activate apoptosis?

Answer 24

Ced8 and Ced9

Question 25

What three capsases execute apoptosis?

Answer 25

Ced 3,6,7