RNA in Translation Flashcards
This form of tRNA only associates with the ribosome.
Peptidyl tRNA
This form of tRNA carries amino acids, bound to it’s 3’ end.
Aminoacyl tRNA
tRNA is a ________ __________ of RNA, folded into a _____ _______ _______.
Single Strand
Quasi Double Helix
At the end of the loop of the RNA strand are:
3 Bases called Anticodon
How many possible anticodons and different tRNA’s?
61 tRNA’s
64 Possible Antiocodons
How many Anticodons without a tRNA?
3
How many possible permeations of anticodon? 4(3) =
64
How do amino acids attach to tRNA?
Aminoacyl-RNA synthetase
Codon & Anticodon pairings are…
Specific & Complementary!
The Genetic Code is the most striking evidence that…
We all evolved from one common ancestor
Left side of Genetic Code?
First mRNA Base
Right Side?
Third mRNA base
Top?
Second mRNA base
AUG =
MET or Start! The only codon which carries MET
UAA
UGA
UAG
STOP SEQUENCE!
The genetic code is somewhat redundant in that…
3rd base is very flexible
These are the facilitators for binding & where codon-anticodon interactions occur…
Ribosomes!
The ribosomes also catalyze..
Peptide Bonds
Two subunits of the ribosome?
Small Subunit
Large Subunit
In large there are 3 binding sites for tRNA.
A - aminoacyl tRNA
P - peptidyl tRNA
E - empty tRNA’s
(From left to right EPA, they go from A>P>E)
Translation begins when the small subunit…
Binds to the 5’ Cap
Close to the 5’ cap will be the..
Start Codon AUG
Start codon AUG’s anticodon?
UAC
This refers to the start of a protein or polypeptide terminated by an amino acid with a free amine group
Amino Terminus
The large subunit will bind…
Aminoacyl-tRNA in P site
T/F This is the only time an aminoacyl-tRNA will be here -
TRUE - Then moves to P site and out
How can we establish the reading frame?
Start Codon, then every three bases from
When does the elongation start?
When new tRNA enters
Elongation is noted by the forming of a…
Peptide Bond, added to the carboxy terminal
The first tRNA passes it’s amino acid to the:
A site, and then out. A->P, new one in A, pass from P, P out E, etc.
How does it make a specific amino acid?
Codon-Anticodon pairings
The ribosome shifts in the __’ direction
3’ direction, while mRNA is read 5’-3’
Termination happens when the…..
Stop Codon hits the A site
Following the stop codon the…
Release Factor enters & hydrolyzes bonds.
The hydrolyzing of the bonds releases the:
Peptide & Empty tRNA
As the ribosome moves downstream and the peptide becomes longer…
Another ribosome will hop on! Polyribosomes. Teamwork.
This process will continue until the tail is completely:
Eaten. Pac-Manned
