Herpesviruses

Question 1

genome type

Answer 1

linear dsDNA

Question 2

capsid structure

Answer 2

icosahedral

Question 3

enveloped?

Answer 3

enveloped

Question 4

tegument

Answer 4

a protective cluster of proteins between the envelope and capsid

Question 5

HSV-1 gene timing

Answer 5

Early = Activates transcription of middle and late genes

Middle = DNA replication

Late = structural

Question 6

Be familiar with the virus life cycle of papillomaviruses. You will not need to write this out from memory

Answer 6

a. Glycoproteins bind multiple receptors but the main is nectin-1
b. pH independent fusion
c. Capsid transported to nuclear pore
d. Linear genome injected into nucleus
e. Circularization
f. Early genes = transcription of middle genes and protect from innate immunity
g. Middle genes = DNA replication
h. Genome amplification by bidirectional replication and rolling circle
i. Late genes = structural genes
j. Nuclear viral factories
k. Move through golgi transport to plasma membrane
l. exocytosis

Question 7

VAP

Answer 7

glycoproteins

Question 8

host receptor

Answer 8

main receptor is nectin-1

Question 9

why is nectin-1 important for HSV-1 pathogenesis?

Answer 9

a. Expressed on epithelial cells and neurons
b. Neurons = latency phase

Question 10

Know when the HSV-1 genome exists as a linear and a circular genome

Answer 10

a. Linear in capsid
b. Circularized in nucleus for replication
c. Linear after rolling circle

Question 11

Understand the pathogenesis of HSV-1 from how it enters the body to latent infection, to reactivation.

Answer 11

a. Intimate contact spreads
b. Infect epithelial cells
c. Replication causes sores
d. Infection of sensory PNS
e. Neuronal ganglia = site of latency

Question 12

How does HSV-1 sense and activate latency

Answer 12

a. Enters neurons
b. Latency mRNA produced which creates a latency switch
c. Represses early protein transcription
d. Replicates only if neuron does

Question 13

What is the only efficacious human herpesvirus vaccine? What type is it?

Answer 13

VZV (chickenpox) is live attenuated

Question 14

How do drugs targeting HSV inhibit virus replication? Can this completely cure someone from HSV infection?

Answer 14

Prevent virus from synthesizing its DNA by inhibiting polymerases or helicase to prevent shedding

Reduces number and severity of outbreaks. Does not cure

Question 15

Site of latency

Answer 15

Neuronal ganglia