-
What is the function of RNA helicase?
Melt out stems in mRNA which is found in initiation and enlongation factors.
-
most EIF, EEF and EFs have multiple...
proteins
-
UTR stands for...
Untranslated Region
-
ORF stands for
Open reading frame
-
the 60S large ribosomal subunit has what components?
-
the 40S small ribosomal subunit has what components?
-
-
All 3 RNA polymers are needed for ...
eukaryotic translation
-
RNA polymerase I consists of..
18S, 28S, 5.8S
-
RNA polymerase II consists of ...
proteins
-
RNA Polymerase III consists of
5S
-
ribosomal subunits are assembled in the .....
nucleolus
-
The ribosomal subunits transcribe ______ which needs to move back to the _________.
-
Once the mRNA moves back to the cytoplasm it translates...
protein
-
After the protein is translated in the cytoplasm is goes back into the...
nucleolus
-
3' 18S has no complement to....
mRNA
-
In Eukaryotic tanslation intiation there is no________ (No shine delgarno)
Ribosomal binding site (rbs)
-
the 5' cap of the 7-methyl guanosine is recognized by...
eIF4
-
The eIF4 binds to _________ and Poly A binds _______.
-
Poly A protein binds to...
Poly A tail
-
eIF4 is involved with what two things regarding eukaryotic tanslation initiation?
The recognition of the 7-methylguanosine cap and the binding of the mRNA to the small ribosomal unit.
-
the 40S ribosomal unite pre-binds what?
trnameti
-
There is no _____ trna in eukaryotes.
f-met trna
-
What makes the main eukaryotic initiation complex (eIF4)
-
The intiation complex moves ______-stream and pauses on the ______.
-
Only ____% of the time, the 1st AUG is used.
90
-
Once the AUG is found by the intiation complex, the _____ binds.
60S
-
What are the four factors that help you pick AUG?
- Short (<10NT) 5' UTR is not translated well
- Kozac Rule: Conserved sequences around the AUG codon that enhances the start.
- If you have a hairpin (stem loop) just the downstream 3' side of AUG will enhance it.
- A strong stem loop close to the cap will black translation
-
Short (<10NT) 5' UTR are usually not _________well
translated
-
Kozac's rule is when.....
You have conserved sequences around the AUG codon that enhances the start.
-
A strong stem loop that is to close to the cap will ________ translation.
block
-
what is needed for optimal translation?
kozacks rules
-
The eukaryotic initiator tRNA is...
tRNAmet
-
the initial binding of mRNA to the eukaryotic ribosome requires a ...
7-methylguanosine
-
The eukaryotic enlongation rate in trnaslation is typically....
2 to 6 amino acids
-
Eukaryotic translation termination requires what two factors?
eRF1 and eRF3
-
eIF1, eIF2 amd eIF6 do what?
prevent association between small and large ribosomal subunits
-
eIF2 does what?
promotes binding of initiator tRNA to the small ribosomal subunit
-
eIF5 does what?
help dissociate other enlongation factors which allows the large ribosomal subunit to bind
-
eEF1 (alpha) function is...
involved in the binding of tRNA
-
eEF1 (beta) function is...
Nucleotide exchange factors required for the functioning of EF-Tu and EFF1 (alpha)
-
The eEF2 function is...
required for tanslocation
-
what is the eRF1 function?
Recognizes a stop codon and triggers the cleavage of the polypeptide from the tRNA
-
what is the eRF3 function?
GTPases that are also involved in termination
-
Which ribosomal sites can be found at a tRNA without an amino acid attached?
The E and P sites
-
a tRNA without an amino acid attached is only briefly found in the P-site, just before _______ occurs
translocation
-
Which ribosomal sites can be found at a tRNA with a polypeptide attached?
The P site and A site
-
A tRNA with a polypeptide chain attached is only briefly found in the ____site, just before translocation occurs.
A-site
-
Which ribosomal sites would you find on A tRNA with a single amino acid attached?
Usually the A site, except the initiator tRNA which can be found in the P site.
-
An mRNA encodes a polypeptide that is 312 amino acids in length. The 53rd codon in this polypeptide is a tryptophan codon.A mutation in the gene that encodes this polypeptide changes this tryptophan codon into a stop codon. How many amino acids would be in the resulting polypeptide: 52, 53, 259, or 260?
52
-
Describe the components of eukaryotic ribosomal subunits and where the assembly of the subunits occurs within living cells.
- 33 proteins and one rRNA assemble to form a 40S subunit,
- 49 proteins and three rRNAs assemble to form a 60S subunit.
- assembly occurs within the nucleolus.
-
Would a bacterial mRNAbe translated in vitro by eukaryotic ribosomes?
The initiation phase of translation is very different in bacteria and in eukaryotes, so they would not be translated very efficiently (bacterial mRNA Lacks cap structure)
-
Would a eukaryotic mRNA be translated in vitro by bacterial ribosomes?
A eukaryotic mRNA would not have a Shine-Dalgarno sequence near its 5' end, so it would not be translated very efficiently in abacterial translation system.
|
|
