1.5

Question 1

Which enzyme helps untangle and refold aggregated proteins?

Answer 1

Chaperones

Question 2

What is a common feature that enzymes interacting with mis-folded proteins shared with one another to enable physical interaction with their protein substrates?

Answer 2

Hydrophobic surface

Question 3

HSP100

Answer 3

A chaperone protein that helps unfold proteins that are aggregated together

Question 4

Which peptidyl prolyl isomerase requires post translational modification of the substrate protein for recognition and subsequent proline isomerization

Answer 4

PIN1

Question 5

What does ATP hydrolysis to ADP cause to happen in HSP70

Answer 5

Closing of the lid in the substrate binding domain

Question 6

What stabilizes amyloid fibril beta strands

Answer 6

-ionic interactions between charged side chains
-hydrophobic interactions between non polar side chains

Question 7

Cyclophilins

Answer 7

-Peptidyl-prolyl isomerases
-can change proline cis to trans

Question 8

FK506 Binding Proteins

Answer 8

-PPI
-Turns proline cis to trans

Question 9

PIN1

Answer 9

-targets proteins that has a serine or threonine before proline
-alters proline cis to trans
-only recognizes after serine and threonine has been phosphorolyzed

Question 10

HSP60 & HSP10

Answer 10

-chaperone
-primary folding chaperones
-GrOES and GroEL

Question 11

HSP70

Answer 11

-delivery chaperone
-regulates translocation to ER
-delivers unfolded proteins to other chaperones

Question 12

HSP100

Answer 12

-unfolding protein
-unfolds misfolded or aggregated proteins

Question 13

What are the 3 componentes of the u folded protein response?

Answer 13

1. Halting translation
2. Increasing the # of chaperones to help with folding
3. Target misfolded proteins for degradation

Question 14

What happens if the unfolded protein response fails?

Answer 14

The cell will undergo programmed cell death/apoptosis

Question 15

How is the accumulation of unfolded proteins recognized,

Answer 15

BIP

Question 16

How does BIP work?

Answer 16

BIP is normally with the proteins ATF6, IRE1, and PERK. When unfolded proteins build up in the ER, it leaves its proteins which activates them

Question 17

PERK1

Answer 17

-stops translation of new proteins when it phosphorylates the translation imitation complex

Question 18

ATF6

Answer 18

-in the golgi ATF6 is cleaved to release and activate the transcription factor domain which turns on genes that help clean up

Question 19

IRE1

Answer 19

-multifunctional protein
-splices mRNA
-degrades mRNA transcripts
-induces apoptosis

Question 20

What is ubiquitin?

Answer 20

A small protein

Question 21

What does Ubiquitylation of Lys residues do?

Answer 21

Targets protein for degradation by the 26S proteosome

Question 22

How are amyloid beta strands highly stable?

Answer 22

1. Salt bridge between lysine and aspartate
2. Hydrophobic interactions between strands