Exam 3- Protein folding and diseases

Question 1

What diseases are associated with protein folding?

Answer 1

Osteogenesis Imperfecta (OI)
Hungtinton’s Disease
Alzheimer’s
TSE or Mad Cow

Question 2

What is Huntington’s disease associated to?

Answer 2

There are two main presentations of this disease, early onset (juvenile Hungtinton’s disease) and late onset (age 40 and above). Characterized by uncoordinated jerky body movements.

Is not fatal by itself but as symptoms progress life expectancy is dramatically reduced.

Huntingtin is a protein that is
Glutamine rich repeats in these proteins
CAG

Causes DNA slippage during replication
DNA polymerase copies this many times on accident

Affects motor and movement coordination

Expansion of Poly-Glutamine (Q) repeats in the sequence of Huntingtin. 27 Qs or less = normal protein; 27 Qs or more = mutated Huntingtin – the protein is mislocalized and misfolded – leads to neuron death.

Question 3

-What is Alzheimer’s disease associated to?

Answer 3

Amyloid Precursor Protein APP

We do not have much information on the physiology of this protein But does lead to amyloid plaques on the brain leading to cell death

Question 4

What is Osteogenesis Imperfecta associated to?

Answer 4

Misfolding in collagen I

Disulfide bonds are not formed correctly, leading to bone fragility.

Question 5

What is Transmissible Spongiform Encephalopathy TSE

Answer 5

Mad Cow Disease

Caused by a Prion

Question 6

What is a Prion

Answer 6

Cause other proteins to form aggregates and misfold

This is an infectious agent that lacks Nucleic Acids

This protein by itself can infect

The diseases that involve prions take a long time to develop