RNA Processing and Transcription Flashcards
What is TFIIH?
It is a transcription factor that phosphorylates the RNA Pol-II CTD which allows transcription initiation
What is TFIID?
It is a transcription factor that contains a TATA-Box binding protein(TBP) and multiple TBP association factors(TAFs).
TBP: binds to TATA box
TAFs: interacts with other transcription factors
What is the function of RNA-Pol-III?
Transcribes DNA to produce tRNA, 5s rRNA, and other small RNAs
What is the function of RNA Pol-I?
Function is transcription of only rRNA including; 28S, 18S, 5.8S (except of 5s rRNA)?
Where does rRNA transcription occur?
In the Nucleolus
What is the function of (sno)RNA and how does it work?
It directs nucleotide modification within rRNAs. Works by base pairs to specific target sequences.
What are the 4 basic steps of pre-mRNA processing?
1) 5’ G-capping
2) Cleavage at Poly(A) site
3) Polyadenylation
4) RNA splicing
Which kind of RNA Polymerase transcripts are not G-capped? Which are G-capped?
All RNA Pol-I and III transcripts are not G-capped.
All RNA Pol-II transcripts are G-capped.
What 2 RNA sequences are important for cleavage and polyadenylation?
AAUAAA and G/U rich sequences
How does the cell known to only cleave and polyadenylate mRNA?
The RNA Pol-II CTD(stimulates cleavage/polyadenylation and interacts with cleavage/polyadenylation factors) and sequence specificity on mRNA(AAUAAA and G/U)
What is the function of the Poly-A tail?
signals termination of RNA Pol-II transcription
What is the functions of miRNA? Where does it bind?
Repress translation and activate mRNA decay. It base pairs with the mRNA 3’ UTR imperfectly.
Wobble position tRNA C base pairs with…
G
Wobble position tRNA A base pairs with…
U
Wobble position tRNA G base pairs with…
C and U
