Flashcards in 2.16 Transcription Deck (15):
What is the Promoter?
Responsible for Binding RNA Polymerase II
What is the Cap Sequence
WHere transcription is initiated
What is the actual nucleotide sequence of the Cap Sequence?
What is the ATG codon responsible for ?
Codon responsible for initiation
What is the TAA codon responsible for?
Where are CAAT and TATA boxes found and what is their role?
Found in the promoter sequence and function to attract polymerase and begin transcription
What are C/EBPs?
transcription factors that recruit other transcription factors and open chromatin
How does the enhancer function?
It can physically interact with the promoter via transcription factor interactions to modulate gene expressions
What are the three steps of Transcription
What occurs during the initiation phase?
RNA Polymerase II binds to promoter
This requires Transcription factors
What occurs during the Elongation phase
Synthesized 5' --> 3'
Antiparallel to DNA sequence
T's are replaced with U's
What is released during elongation each time a NT is added
What occurs during Termination phase
5' cap is applied which is methylated guanosine
3' end receives a poly A tail
What are the two post-transcriptional modifications that concern the cap and tail?
5' cap of methylated guanosine is installed in 5' to 5' polarity bound by three phosphates
3' terminus is modified by having roughly 200 A residues added. This gets shorter as mRNA ages