isolate cell surface proteins -> immbolize proteins in chromotography column -> test for virus binding
mix virus w/ cell protein extract -> chemically induce crosslinking -> look to see what has bound to virus
mRNA from permissive cell is obtained and converted into cDNA library -> inserted into nonpermissive cells (one of which will now contain the receptor protein ) -> a previosly non permissive will become permissive -> recover and sequence
what is critical in transitioning from attachement to uncoating
fusion can take place
-internally (more common): endosome or lyzosome
typicall when something comes from the exterior of the cell to the interior, it becomes more
acidic, but some viruses take advantage of that
how are the more important receptors determined
inducing certain mutations
influenza spike proteins
1. Hemagglutinin (HA)
2. Neuraminidase (NA)
what type of virus does not require a fusion protein
fusion of enveloped virus
virus just fuses in
endocytosis of an enveloped virus
vesicle forms around viral envelope
most animal virues
primary binding protein
what dictates where most of the replication will take place
viruses will utilize what to carry the virus to the nucleus?
what is an example of a virus that has replicates unusually?
how do plant viruses infect?
through broken/damaged parts (mechanical destruction from insects chewing)
reproductive structures are also susceptible
what structure in plants allow the spreading of a virus once its in?
plant immune defense
chemicals that kill the tissues before further spreading
helps direct RNA polymerase where to start
T7 DNA replication proteins
1. gp 2.5 (viral) : ss binding protein
2. gp 4 (viral): helicase and primase
3. gp 5 (viral): polymerase
4. Trx (host): aid processivity
MS2 genes (4)
2. RdRp gene
3. A protein
4. lysis protein
what is RdRp
RNA dependent RNA polymerase
which MS2 gene is in high abundance?
which MS2 gene is in low abundance?
the phi chi 174/phi x 174 has a ___________ genome
how are the genes in bacteriophage lambda expressed? (3)
1. immediate early
if the virus has a complicated structure, you can assume that there are lots of
under good growth conditions, bacteriophage lambda favors
under poor growth conditions, bacteriophage lambda favors
lambda gene expression
1. immediate early
2. expression of N gene (transcriptional antiterminator) and protein (Pl promoter)
3. Cro gene and protein (Pr promoter)
what does the transcribing in bacteriophage lambda?
what does the N protein do?
binds to the terminator stem loop and recruits host protein
what does Q protein do?
causes more antitermination which late gene expression