transcription 3 Flashcards
what is the main difference in eukaryotic gene regulation compared to prokaryotic
eukaryotic genes are individually regulated
why are eukaryotic genes individually produced and regulated
because certain genes may be used to make different things for different purposes
what transcribes all genes that encode proteins
rna polymerase 2
how many units does rna polymerase 2 have
12
what can rna polymerase cannot do
it cannot initiate transcription
what do eukaryotic transcription factors do
help rna polymerase bind
what do transcriptional activators do
they help attract rna polymerase 2 to the promotor region and to regulate rate and gene expression
what are ‘other proteins’ responsible for
sorry lol that’s legit what they’ve called them
unwinding chromatin to allow access for the transcription factors
how do proteins recognise the promoter region
the major groove of the double helix
what does the core promoter contain and at what location
TATA box at -30
initiator at +1
where is the enhancer located
-1000
where are the upstream sequence elements located
-100
how does initiation begin in eukaryotes
the TFII position rna pol 2 and separate the dna
which is the first protein to bind and what are the units they contain and what do they do
TFII2
its units are TBP - which recognises and binds to tata bo
TAFs allows other transcription factors to bind
what is the order of proteins binding
lol sorry
TFIID
TFIIA
TFIIB
rna pol
TFIIF
TFIIE
TFIIH
what is TFIIE and TFIIH
E- atpase
H- helicase
what do all the transcription factors and rna pol form
pre-initiation complex
what happens as elongation begins to occur
(hint - 4 things)
the c terminal will be phosphorylated
there will be conformational change in the rna pol and it will tighten
tfs will dissoicate
rna pol will acquire elongation proteins
what does a core promoter that does not contain a tata box have and what transcription factor will recognise it
initiator and a downstream promoter element
will be recognised by TF2 I
what will upstream sequence elements carry out
tissue specific enhancment
what are the three types of upstream sequence motifs
-bound by general transcription
-allow tissue-specific expression
-a response to stimuli
which way do enhancers work
either orientation
what does the enhancer interact with
the PIC
what do different cell types have
different activator proteins
