Please enable JavaScript.
Coggle requires JavaScript to display documents.
preinitiation complex for class l (rRNA promoter) Transcription factor,…
preinitiation complex for class l (rRNA promoter)
Transcription factor
UPE-binding factor (upstream-binding factor (UBF) or upstream activating factor (UAF) )
UPF is assembly factot
helps core binding factor to bind to core promoter elemnt
architectural transcription factor
stimulates transcription by pol l
can activate the intact promoter, or core element alone
mediates the activition by UPE
core-binding factor (SL1 or TIF-IB)
SL1 required for
recruit RNA polymerase l
basal transcription activity (help in initiation)
TIF-IB
recruit RNA polymerase l and stimulate initiation in the proper place (downstream)
add or delete up to 50bp between TIF-IB site and transcription start site to allow transcription to occur
initiation site move upstream or downstream depend to mutation type
composed of
TBP
3 TAFs ( TAF I 110, TAF I 63, TAF I 48)
Class ll Factors
TFlllC
assembly factor allow TFlllB to bind
TFlllA
required only for 5s rRNA
anti-TFlllA
inhibits 5s rRNA but has no effect on tRNA
first member of DNA-binding proteins that have zinc finger
4 amino acid bind a zinc ion
3 Cys + 2 His
OR
4 Cys
nine zinc fingers
bind to major groove
TFlllB
required for transcription of pol lll genes
can remain bound and sponsor initiation of repeated transcription rounds
preinitiation complex
TFlllC bind to ptomoter
TFlllB with it is TBP bind to upstream
poly lll bind in start site
TFIIIC remove
Transcripyion start
pol lll
tRNA
5s rRNA
UPF can not bind by it self but SL1 can
SL1 and UBF bind cooperatively and UBF stimulates rRNA transcription
suzan albordaini
201703178