Polyomaviridae and Prions

Question 1

List 5 polyomaviruses and describe the structure and genome of one of them.

Answer 1

1. JCV: Archetype; contains A-F regions: divisions roughly define blocks of sequence that are deleted or duplicated and rejoined as units. Rearranged; A (containing TATA box), first half of C & E always retained. B, D & F may be deleted or retained.
2. BK
3. KI
4. WU
5. MCV

Question 2

List the diseases associated with Polyomavirus BKV, JCV, and MCV infection in humans.

Answer 2

BKV: hemorrhagic cystitis, polyomavirus nephropathy.
JCV: AIDS, leukemia/lymphoma, myeloproliferative disorders.
MCV: Merkel cell carcinoma.

Question 3

Describe PML.

Answer 3

a sub-acute demyelinating disease among
immunocompromised individuals.

Question 4

What are prions?

Answer 4

proteinaceous transmissible pathogens responsible for a series of fatal neurodegenerative diseases.

Question 5

Describe three types of prion diseases. Give examples.

Answer 5

1. Sporadic: sixth or seventh decade, rapidly progressive (death in less than a year). Example: Creutzfeldt-Jakob disease (CJD).
2. Familial: mutations in the PrP gene that favour the transition from the cellular to pathological form. Example: Gerstmann-Straussler-Scheinker disease
   (GSS).
3. Transmissible: in the laboratory, the disease is transmitted to mice via intracranial injection from a prion-infected animal. Example: CJD to vCJD.

Question 6

What are the symptoms of Kuru and CJD?

Answer 6

• Kuru: slurred speech, loss of coordination in lower extremities, mental slowing, jerky movements, difficulty swallowing, deep ulceration.
• CJD: dementia, hallucinations, motoric dysfunction.

Question 7

Describe the characteristics of classic and variant CJD.

Answer 7

*screenshot (camera roll)