Transcript doesnt become message until leave nucleus.
Promoter, enhancer (stimulate initiation and transcription). Introns (first from adenovirus)
RNA synthesis is initiated and regulation
When virus enter cell, first thing is to get transcribe
Virology: Infectious cycle- attachment and entry
Susceptible cell- has receptor for virus
Resistant cell- has no receptor for virus
Permissive- can replicate virus (doesnt matter about receptor)
Need to be susceptible AND permissive cell for virus to be t
Herpes simplex virus brings in VP16, activate all immediate early gene products, potent
transcriptional activators, etc. Autoregulator loops.
DNA virus transcription:
-Polyoma 2 transcriptional units, multiple splicing.
Adenovirus have 8 transcriptional u
HIV requires step of integration. Must take RNA genome, intergrate into host, it is linear
molecule. Long terminal repeat. First product made is full length RNA, spliced in two
parts- Rev. Rev is protein that induced splicing throughout genome, allow prop
Specify accurate initation, respond to host and virus proteins, synthesize de novo RNA
-Recognize core promoter, form stable closed initiation complex (nothing happens). Want
to open complex- allow access by helicase to unwind, allow initiati
First must get inside nucleus!
-Hep B must be completed.
-Adenovirus/polyoma enter cell nucleus. Some sequences are readily accessible.
Early genes transcribed, lead to cascade of virus genes.
-Herpes- introduce virion- associated protein (loaded and read
1 for many bacteriphages, high for animal viruses so hard to study and determine
if something is infectious or not.
-Not all particles are infectious, infectious cycle needs to be done in correct order.
One step growth cycle
-E.coli bacteriophages: adsorb
Not reversible, assembly pathway is irreversible in cell, reversible in uninfected
cell receiving virion.
- Assembly depends on host- all proteins are virus encoded, need cell functions to
fold into protein molecules.
- Transport system move