Alberts, Ch 18 - Cell Death

Question 1

Anti-IAP

Answer 1

Produced in response to various apoptotic stimuli and neutralize inhibition of apoptosis provided by IAPs by binding to IAPs and preventing their binding to caspase

Question 2

Apaf1

Answer 2

Adaptor protein of intrinsic apoptotic pathway, on binding cytochrome coligomerizes to form an apoptosome

Question 3

Apoptosis

Answer 3

Form of programmed cell death, a suicide program is activated within animal cell leading to rapid cell death mediated by intracellular proteolytic enzymes calles caspases

Question 4

Apoptosome

Answer 4

Heptamer of Apaf1 proteins that forms on activation of intrinsic apoptotic pathway, recruits and activates initiator caspases that activate downstream executioner caspases to induce apoptosis

Question 5

Bak

Answer 5

Main effector Bcl2 family protein of intrinsic pathway of apoptosis that is bound to mitochondrial outer membrane even in absence of an apoptotic signal, activation by pro-apoptotic BH3-only protein

Question 6

Bax

Answer 6

Main effectos Bcl2 family protein of intrinsic pathway of apoptosis, located mainly in cytosol and translocates to mitochondria only after activation, activated by pro-apoptotic BH3-only proteins

Question 7

Bcl2

Answer 7

Anti-apoptotic Bcl2 family protein of outer mitochondrial membrane that binds and inhibits pro-apoptotic Bck2 family proteins and prevents inappopriate activation of intrinsic apoptosis pathway

Question 8

Bcl2 family

Answer 8

Family of intracellular proteins that either promote or inhibit apoptosis by regulating release of cytochrome c and other mitochondrial proteins from intermembrane space into cytosol

Question 9

BclXL

Answer 9

Anti-apoptotic Bcl3 family protein of outer mitochondrial membrane that binds and inhibits pro-apoptotic Bcl2 family proteins and prevents inappropriate activation of intrinsic apoptosis pathway

Question 10

BH3-only protein

Answer 10

Largest subclass of Bcl2 family proteins, produced or activated in response to apoptotic stimulus and promote apoptosis mainly by inhibitng anti-apoptotic Bcl2 family proteins

Question 11

Caspase

Answer 11

Intracellular protease that is involved in mediating intracellulat events of apoptosis

Question 12

Cytochrome

Answer 12

Colored heme-containing protein that transfers electrons during respiration and photosynthesis

Question 13

Cytochrome c

Answer 13

Soluble component of mitochondrial electron-transport chain, its releas into cytosol from mitochondrialintermembrane space initiates apoptosis

Question 14

Death receptor

Answer 14

Transmembrane receptor protein that can signal the cell to undergo apoptosis when it binds its extracellular ligand

Question 15

Death-inducing signaling complex (DISC)

Answer 15

Activation complex in which initiator caspases interact and are activated following binding of extracellular ligands to cell-surface death receptors in extrinsic apoptosis pathway

Question 16

Effector Bcl2 family proteins

Answer 16

Pro-apoptotic proteins of intrinsic apoptosis pathway that in response to apoptotic stimulus activated and aggregate to form oligomers in mitochondrial outer membrane inducing release of cytochrome c and other intermembrane proteins, Bax and Bak are main effector Bcl2 family proteins

Question 17

Executioner caspase

Answer 17

Apoptotic caspases that catalyze the widespread cleavage events during apoptosis

Question 18

Extrinsic pathway

Answer 18

Apoptosis pathway triggered by extracellular signal proteins binding to death receptors

Question 19

Fas

Answer 19

Transmembrane death receptor that initiates apoptosis when it binds its extracellular ligand

Question 20

Fas ligand

Answer 20

Ligand that activates Fas triggering extrinsic apoptosis pathway

Question 21

Inhibitors of apoptosis (IAPs)

Answer 21

Intracellular protein inhibitors of apoptosis

Question 22

Initiator caspases

Answer 22

Apoptotic caspases that begin apoptotic process activating executioner caspases

Question 23

Intrinsic pathway

Answer 23

Apoptosis pathway activated from inside. The cell in response to stress or development signals, depends on release of mitochondrial proteins into the cytosol from mitochondrial intermembrane space, also known as mitochondrial pathway

Question 24

Survival factor

Answer 24

Extracellular signal that promotes cell survival by inhibiting apoptosis

Question 25

Anti-apoptotic Bcl2 family proteins

Answer 25

Proteins on cytosolic surface of outer mitochondrial membrane that bind and inhibit pro-apoptotic Bcl family proteins and help prevent inappropriate activation of intrinsic pathway of apoptosis