AAVs Flashcards
What is the adeno-associated virus genome?
ssDNA 4.7kb
What are their promoters?
p5 and p19
Where does Rep gene intergrate?
chromosome 19
What life cycle do AAVs have?
Latent until adeno/herpes infection into the cell.
How do AAVs replicate?
Insert into genome via site specific inverted terminal repeats found at either end of genome
What are 4 pros of AAVs?
Not pathogenic, no viral gene expression, wide range of cells and intergrate into genome.
What are 3 cons to AAVs?
Limited packaging, Rep and helper virus required
AAV needs EA1 gene for what?
Activates AAV gene expression
AAV needs E1B and E4 for what?
stabilise genome and facilitate transport
AAV gene needs E2A for?1
efficient AAV RNA splicing and transcription
AAV gene needs VA RNAs for what?
Stimulates efficient transltion
What 5 adeno genes do AAVs need?
E1A, E1B, E2A, E4 and VA RNAs.
How main strains of AAV are there?
6
What tissues does AAV2 infect?
neuronal
What does AAV5 infect?
Epidermal
What is immune reaction?
Produces many neutralising antibodies cannot readminister
What must be in a fake AAV genome?
Packaging sequence, terminal repeat, Reb, therapeutic gene.
Why does Reb need to be included in AAV vector?
Without Red AAV will intergrate randomly at sites of high translation eg chromosome 12
How big can therapeutic gene be?
2.3kb
How can a larger target gene be incorportated?
2 AAVs splice them together to make 1 mRNA
What are AAV2s good at treating?
AAVs 2 containg 7/8 cap gene treating Haemophillia
What factors is haemophilia due to?
Factors 8 (85%) and 9
What can AAVs treat?
Haemophillia and retinal degreneration?
