Viruses: General Principles

Question 1

What are the 6 stages in viral replication?

Answer 1

1. Attachment
2. Penetration
3. Uncoating
   4a. Genome replication
   4b. RNA synthesis
   4c. Protein synthesis
4. Assembly
5. Release

Question 2

How does an RNA virus replicate?

Answer 2

Genome is a linear ss + sense RNA

• can make a polyprotein
• doesen’t do anything, it folds up and makes an active site that it recognises itself –> autocleavage to produce RNA pol
• -> can then go and synthesise new strands

Question 3

What is the difference between +ve sense RNA and -ve sense RNA viruses?

Answer 3

+ve sense RNA viruses encode their own RNA pol

-ve sense RNA viruses carry the polymerase with them

Question 4

What is recombination of viruses?

Answer 4

Exchange of stretches of nucleic acid between genomes of similar sequence

Question 5

What is reassortment of viruses?

Answer 5

Swapping of segments for viruses that have segmented genomes