Influenza

Question 1

Structure

Answer 1

• HA; NA
• Matrix protein

•helical nucleocapsid
-> 8 distinct segmented ssRNA(-)

•RDRP= 4 proteins

Question 2

Function of RDRP

Answer 2

-make (+)ssRNA
-> replicate neg sense virus RNA;
Synthesis virus protein

Question 3

Describe attachment and penetration

Answer 3

• HA attaches to sialic acid receptor on epithelial cells of respiratory tract;
• RME;
• host cytoplasmic membrane invaginate and pinches off;

=> virus in endocytic vesicle

Question 4

Describe uncoating

Answer 4

Low pH

• > stimulate viral envelope to fuse with lipid bilayer of vesicles membrane
• > releasing nucleocapsid
• > capsid degraded
• > releasing 8 ssRNA (-) genomes

Question 5

Describe synthesis

Answer 5

ssRNA(+) —> ssRNA(-)

For
1.
a) mRNA to make virus protein
b) template for making new viral saRNA(-) genome

2. Exported from nucleus to cytoplasm for translation into:

a) capsid protein and virus protein
b) glycoproteins

Question 6

Describe assembly

Answer 6

-capsid assembled around each viral genome

• HA and NA
• > secreted;
• > transported

Question 7

Describe release

Answer 7

• new virus buds from host cell acquire new coat; covered in sialic acid
• removed by nuramindase so that do not clump