Autophagy

Question 1

Aggregate-prone proteins (e.g. those with expanded stretches of glutamine residues in diseases like Huntington’s disease) will cause

Answer 1

neuronal cell death

Question 2

Autophagy degrades _______. No toxic stimulus, no _______.

Answer 2

• the aggregate-prone proteins (perhaps after they have started to form small aggregates)
• neuronal cell death

Question 3

Many proteins - e.g. Bcl-2 - that regulate apoptosis/ cell death, also control

Answer 3

autophagy–remember, this could create problems in interpreting results of therapeutic interventions designed to target these proteins.

Question 4

_______ can cleave essential autophagy regulators, _______ them and therefore _______ the process of autophagy.

Answer 4

• Apoptotic proteases (caspases)
• inactivating
• blocking
• **In some cases, -e.g. with starvation-induced cell death, it is easy to see why autophagy would protect– it provides essential nutrients at least in the short term. In others, e.g. stress-induced cell death from chemotherapy etc. its less clear why autophagy would be protective.

Question 5

_______(best studied)- form a double membrane vesicle that captures cytosolic components/organelles. Then fuse with lysosome where hydrolases degrade contents of autophagosome.

Answer 5

Macroautophagy

Question 6

Macroautophagy (best studied)- form a _______ that captures cytosolic components/organelles. Then fuse with _______where hydrolases degrade contents of _______.

Answer 6

• double membrane vesicle
• lysosome
• autophagosome

Question 7

Macroautophagy (best studied)- form a double membrane vesicle that captures _______. Then fuse with lysosome where _______ degrade contents of autophagosome.

Answer 7

• cytosolic components/organelles

- hydrolases

Question 8

_______–recognition of specific proteins that contain a specific recognition sequence (based on amino acid sequence KFERQ). Direct binding and delivery to lysosome.

Answer 8

Chaperone-mediated

Question 9

Chaperone-mediated–recognition of specific proteins that contain a _______. _______binding and delivery to lysosome.

Answer 9

• specific recognition sequence (based on amino acid sequence KFERQ)
• Direct

Question 10

Chaperone-mediated–recognition of specific proteins that contain a specific recognition sequence (based on amino acid sequence KFERQ). Direct binding and delivery to _______.

Answer 10

lysosome

Question 11

macroautophagy 1: Activate a _______ that allows _______ that will eventually form an _______.

Answer 11

-PI3K complex
nucleation of a membrane
-autophagosome

Question 12

macrophagy 2: Regulation of _______

Answer 12

-protein conjugation events to extend membrane.

Question 13

macrophagy 3: Randomly capture, or specifically deliver cargo to _______, then _______ to _______.

Answer 13

• the extending aytophagosome
• join the membranes
• close the vesicle

Question 14

macrophagy 4: Fuse with _______. Recycle _______ and _______

Answer 14

• lysosome
• amino acids
• other macromolecular precursors