EBV part III Flashcards
2 functions of EBNA1?
tethers EBV viral genome to the host chromosomes
helps distribute genome into daughter cells during latent replication.
What is unusal about EBNA1 amino acid sequence?
It has alot of glycine and alanine repeats?
What effects do the alanine and glycine repearts within EBNA1 aa sequence mean?
poor proteosomal degradation
unusal RNA secondary structure, so poor translation.
low levels of EBNA1 with a long half life.
EBNA1 is inefficiently targeted by CD8 T cells.
3 examples of immediate-early, early and late proteins in lytic infection?
BZLF1, BMLF1, BLLF1
Which of the 10 unique lytic cycle genes mediate immune evasion?
BNLF2A
What are the effects of BNLF2A?
Inhibition of peptide-TAP binding, and ATP-TAP binding. Leads to HLA I downregulation.
What stage of lytic infection does BNLF2A immune evasion work in?
in immediate early stages of lytic cycle (low expression at later time points)
What are the effects of BILF1?
BILF1 increases the turnover of MHC I and directs MHC I to lysosomes for degradation.
Which HLA does BILF1 spare?
spares HLA-C, maintains it for NK cell inhibition.
How does BGLF5 cause a decrease in MHC I synthesis?
inhibits host shut off protein.
What does BDLF3 increase to decrease MHC I expression?
incrases MHC I ubiquitiantion and internalisaiton.
Which immune evasion proteins haev late and later expression in lytic cycle?
BILF1 and then BDLF3.
