MOLECULAR MECHANISMS

Question 1

activated enzymes cleave targets resulting in the release of?

Answer 1

nucleases that degrade the DNA

Question 2

what are the two pathways?

Answer 2

mitochondrial pathway (intrinsic)

death receptor pathway
extrinsic

Question 3

name this pathway?

choice between whether or not apoptosis will occur is determined by permeability of the mitochondria

Answer 3

mitochondrial (intrinsic) pathway

Question 4

name this pathway?

a large number of cells express surface molecules called death receptors which trigger apoptosis (TNF receptor family)

Answer 4

death receptor (extrinsic) pathway

Question 5

in the intrinsic pathway, what are the sensors that inhibit antiapoptotic molecules?

Answer 5

Bcl-2 and Bcl-xL

Question 6

what sensors activate pro-apoptotic molecules?

why are these significant?

Answer 6

Bax & Bak

dimerization and inserted into the mitochondrial membrane

Question 7

what specifically activates the caspases in the mitochondrial pathway (intrinsic)?

Answer 7

cytochrome C

Question 8

so the extrinsic pathway or the death receptor pathway has what prototypic death receptors?

Answer 8

type 1 TNF, Fas (CD95)

Question 9

what is the significance of the prototypic death receptors?

Answer 9

death domain in the cytoplasm

mediates interactions with other proteins

Question 10

activation of the death receptors does what?

Answer 10

caspase-8 aggregates and leads to this pathway activation which then can activate the pro-apoptotic members (remember these names?) that feeds into the mitochondrial pathway