Apoptosis

Question 1

Role of apoptosis

Answer 1

Normal embryonic devt

Adults: tissue homeostasis

Question 2

C. Elegans is a good model organism bc

Answer 2

• small
• transparent
• every cell mapped out
• genome sequenced
• short developmental program

Question 3

Mutations in _______ block apoptosis in C. Elegans

Answer 3

ced-3

Question 4

Morphological steps

Answer 4

1. Chromatin and cytoplasm condensation
2. Morphological change to nucleus- break up envelope, fragments
3. Cell shrinks
4. Blebs at outer membrane
5. Phagocytosis of blebs

Prevent damaging immune response

Question 5

Apoptosome

Answer 5

Cytochrome C + 7Apaf-1 + 2Caspase 9

Cyt c brings Apaf-1 monomer
= Apaf-1 hexamer
= recruits 2 Caspase 9 monomers on underside of wheel, dimerize
=+apoptosome 
Cleave downstream effectors

Question 6

Caspase cleaves

Answer 6

DNase inhibitors
Nuclear lamins
Cytoskeletal proteins, actin, myosin, alpha-actinin, tubulin, vimentin
Golgi matrix proteins

Question 7

Caspase

Answer 7

Cysteine-dependent aspartate-directed proteases

Question 8

Bcl-2

Answer 8

Pro-survival
B cell lymphoma
Like ced-9 in c elegans
Bcl-2 homology BH domains

Question 9

Bcl-2 family pro- survival

Answer 9

BH1->BH4

Question 10

Bcl-2 family pro- apoptosis

Answer 10

1. BH1->BH3
   Bak Bax Bok
   Form channels in outer mitochondrial membrane
2. BH3 only proteins
   Puma
   Regulate activity of Bcl-2 and Bax/Bak proteins