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!