Translation presntion by me
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Transcript of Translation presntion by me
BIO CHEMISTRY PRESENTATION
MADE BY UMME HABIBATOOBA SHEIKHUMEMA ZUBAIR UMAIR AHMED
3. Translation - making proteins
Nuclearmembrane
Transcription
RNA Processing
Translation
DNA
Pre-mRNA
mRNA
Ribosome
Protein
Eukaryotic Cell
Translation occurs on ribosomes
in three steps:
Ribosome moves towards the 3’ end
Translation
Three parts:1. initiation: start codon (AUG)2. elongation:3. termination: stop codon (UAG, UAA, UGA)
Let’s make a PROTEIN!!!!.
Start codon is AUG; first amino acid is always methionine, which may be removed after translation.
The large subunit joins the complex, the charged tRNA is now in the P site of the large subunit.
Initiation factors are responsible for assembly of the initiation complex.
Initiation
mRNA
A U G C U A C U U C G
2-tRNA
G
aa2
A U
A
1-tRNA
U A C
aa1
anticodon
hydrogenbonds codon
Elongation: the second charged tRNA enters the A site.
When the first tRNA has released its methionine, it moves to the E site and dissociates from the ribosome—can then become charged again.
Elongation occurs as the steps are repeated, assisted by proteins called elongation factors.
Large subunit catalyzes two reactions:
Breaks bond between tRNA
in P site and its amino acid
Peptide bond forms between that amino acid and the amino
acid on tRNA in the A site
1
2
mRNA
A U G C U A C U U C G
1-tRNA 2-tRNA
U A C G
aa1 aa2
A U
A
anticodon
hydrogenbonds codon
peptide bond
3-tRNA
G A A
aa3
Elongation
mRNA
A U G C U A C U U C G
1-tRNA
2-tRNA
U A C
G
aa1
aa2
A U
A
peptide bond
3-tRNA
G A A
aa3
Ribosomes move over one codon
(leaves)
mRNA
A U G C U A C U U C G
2-tRNA
G
aa1
aa2
A U
A
peptide bonds
3-tRNA
G A A
aa3
4-tRNA
G C U
aa4
A C U
mRNA
A U G C U A C U U C G
2-tRNA
G
aa1aa2
A U
A
peptide bonds
3-tRNA
G A A
aa3
4-tRNA
G C U
aa4
A C U
(leaves)
Ribosomes move over one codon
mRNA
G C U A C U U C G
aa1aa2
A
peptide bonds
3-tRNA
G A A
aa3
4-tRNA
G C U
aa4
A C U
U G A
5-tRNA
aa5
mRNA
G C U A C U U C G
aa1
aa2
A
peptide bonds
3-tRNA
G A A
aa3
4-tRNA
G C U
aa4
A C U
U G A
5-tRNA
aa5
Ribosomes move over one codon
Termination: translation ends when a stop codon [UAA, UAG, UGA] enters the A site.
Stop codon binds a protein release factor—allows
hydrolysis of bond between
polypeptide chain and tRNA on the P
site.
mRNA
A C A U G U
aa1
aa2
U
primarystructure
of a protein
aa3
200-tRNA
aa4
U A G
aa5
C U
aa200
aa199
terminator or stop codon
Termination
Polypeptide chain: C terminus is the last amino acid added.
Enzymes degrade mRNA!
The ribosome subunits
dissociate.
End Product
The end products of protein synthesis is a primary structure of a protein.
A sequence of amino acid bonded together by peptide bonds.
aa1
aa2 aa3 aa4aa5
aa200
aa199
This m-rna can again be translated by the same or any other ribosomes to form the multiple copies of that protein!!!
THANK YOU!