L35_DNA Viruses 2 Flashcards
Name some infections that herpesviruses cause?
Chickenpox, mononucleosis, Birth Defects, Cancer
How many human herpes viruses are there?
8
What strain is genital herpes, above the waist?
HSV 2 (genital) HSV 1 (above waist)
describe the genome of herpes virus
Liner dsDNA
How does herpes virus enter the cell?
It binds to surface proteins and fuses or is endocytosed.
Where does herpes virus capsid uncoat?
The nuclear pore
What happens to the herpesvirus genome when it enters the nucleus?
It circularizes
Describe the stages of transcription of herpersvirus
Immediate Early (Transcription factors), Early (replication proteins), Late (capsid proteins)
Where is the capsid formed for new herpes virus virions?
In the nucleus
What polymerase is used for replication of herpesvirus?
The viral DNA polymerase
How does Herpesvirus egress?
exocytosis
Do all herpesviruses have the same tissue tropism?
NO
Where does herpesvirus get its envelope?
First from nuclear membrane, then it gets its tegument, then gets a second envelope from the trans golgi network.
Is the cell killed in the production of herpesvirus?
Not necessarily, cells can shed virions without being killed
What is the definition of latency
The genome is present in a cell but infectious virions are absent.
When does latency occur?
Immediately upon infection, before any symptoms present, this is why we can get rid of it once its there.
How is HSV1 spread?
Spread by close contact with active lesions or asymptomatic shedding
What type of infection usually occurs in children with HSV1?
Gingivostomatitis (lesions on mouth, face, nose, and eyes)
What cells does herpes virus become latent for life for both HSV1 and HSV2?
Neurons (terminal non-differentiated)
What is the prodrome of recurrent HSV1?
Tingling and itching
What can trigger an HSV1 recurrent outbreak?
Fever, sunlight, hormones, stress, physical trauma, etc.
Where do recurrent mouth lesions originate from?
Trigeminal ganglion.
What part of brain to HSV viruses tend to target?
The temporal lobe
What type of neurological infections can HSV cause in primary and secondary infections?
Primary- meningitis (stiff neck and headache)
Secondary- Encephalitis (Fever and Neurological symptoms)
How is HSV2 spread?
Spread by close contact between mucous membranes (genital and/or oral)
What are the symptoms of HSV2
many lesions, pain, itching, fever, malaise, headache (usually but not always below waist