Viroids + Prions Flashcards
1
Q
Viroids + Prions are…
A
Subviral agents
2
Q
Viroids: Morphology
A
- Circular + ssRNA
- Superhelical
- Non strucutral proteins
3
Q
Viroids: Resistance
A
Extremely strong
4
Q
Viroids: Biological proteins
A
- Plant pathogens
- Infection via gardening tools
- Host spectrum: Varies, no orphan viroid
5
Q
Viroids: Examples
A
- Potato spindle tuber viroid
- Hop stunt viroid
- Coconut cadang-cadang viroid
6
Q
Prions: Etymology
A
Protein of infectious nature
7
Q
Prions: Morphology
A
- Pure protein
- The infectious particle does not contain nucleic acid
8
Q
Prions: Resistance
A
- Extremely high
- Lipid solvents reduce heat resistance
9
Q
Prion: Biological properties
A
- Cellular prion protein
- Resistant to proteases
- The normal component of the neurons
- Isoform: A-helix → b-sheet
10
Q
Prion: Pathogenesis
A
- Gut → spleen, lymph nodes → Nerves
- Modulatory protein in nerves
- Induce neurons to produce PrPsc (Infectious prion protein)
- Amyloid plaques - Neuron degradation → Spongiform encephalopathy
- Progressive CNS symptoms
11
Q
Prions: Antigenic properties
A
- Non-antigenic
12
Q
Prions: Diagnosis
A
- Clinical signs
- Histopathology: Vacuolisation of neurons, amyloid plaques
- Proteinase K digestion, IF, Western blot
13
Q
Prions: Examples
A
- Transmissible spongiform encephalopathies (TSEs)
- Scrapie
- Bovine spongiform encephalopathy (BSE)
- Feline spongiform encephalopathy (FSE)
- Transmissible mink encephalopathy (TME)
- Chronic wasting disease (CWD)
- Exotic ungulate encephalopathy
- Progressive dementia
- Creutzfeld-Jakob disease (CJD)
- Variant CJD (vCJD)
- Gerstmann-Sträussler-Scheinker syndrome (GSS)
- Fatal familial insomnia
14
Q
Scrapie
A
Sheep
- Incoordination
- Swaying
- Itching
15
Q
Chronic Wasting disease (CWD)
- Species
- Location
A
- Mule
- Deer
- Elk
North America
