Protein Synthesis Flashcards
What is Transcription?
- The synthesis of RNA from a DNA template
What is translation?
- The synthesis of proteins from mRNA
What are the 3 RNA binding sites?
A site
P site
E site
What happens at the E binding site?
- this is an mRNA binding site
- Releases the used tRNA into the cytoplasm
What happens at the P binding site?
This site holds one amino acid (The tRNA and the growing chain of amino acids attached)
What happens at the A binding site?
Where the tRNA and the next amino acid attaches
What is an elongation factor?
elongation factors deliver aminoacyl-tRNA to the A binding site on the ribosome
What is the structure of tRNA?
- A single strand of bases which binds to itself to create loops
What is the Anticodon loop?
A loop that is very important due to it containing Inosine which can base pair with C, A or U
What is the 3D structure of tRNA?
an L shape
What is the CCA arm?
The CCA arm is present on one end of the tRNA and allows for proofreading of amino acids due to its ability to move
What is Aminoacyl-tRNA also known as?
tRNA ligase
What does Aminoacyl-tRNA do?
It attaches the appropriate amino acid to the tRNA
How is aminoacyl-tRNA bonded?
- the hydroxyl group of the tRNA is esterified to the 3’ end of an amino acid
Where is Aminoacyl-tRNA located?
in the binding site of a ribosome
What is synthetase?
- a set of enzymes that couple each amino acid to its tRNA molecule
What is an Initiator?
- A special methionine tRNA that binds to the initiation codon at the start of translation
How many reading frames are possible?
- 3
What is the mechanism of protein synthesis?
- it requires translation of nucleotide sequences into amino acid sequences
Does Synthase require energy?
NO
Does synthetase require energy?
YES - usually in the form of ATP
What is the wobble hypothesis?
The wobble hypothesis is that the binds between tRNA and the amino acid aren’t set and allow the tRNA molecules to recognise more than 1 codon
