lecture 25 - globular protein misfolding diseases

Question 1

list examples of globular protein misfolding diseases

Answer 1

• alzheimers
• huntingtons
• parkinsons
• type 2 diabetes
• prion
• amyloidoses (formation of amyloid fibrils from misfolded proteins)

Question 2

explain amyloids

Answer 2

• rich in beta structure
• stacked layers of beta sheets
• pack together to form layers

Question 3

what enhances the likelihood of forming amyloids? how?

Answer 3

• mutations
• destabilize native fold AND/OR
• stabilize misfolded state

Question 4

describe alzheimers in relation to amyloids

Answer 4

• amyloids accumualte in the brain
• starts from a pecursor: amyloid precursor protein (APP) which is a membrane protein
• this proteins then cleaved by proteases into a smaller N-term peptide
• this fibril then grows and disrupts cellular structure

Question 5

describe prions

Answer 5

• infectious proteins with no nucelic acids
• e.g. scrapie, BSE
• these are the misfolded form of a normal protein
• then catylizes the misfolding of normally folded form