Protein Synthesis

1
Protein Synthesis
2
Protein Synthesis
3
Protein Synthesis

• Transcription
• DNA ? mRNA
• Occurs in the nucleus

• Translation
• mRNA ? tRNA ? AA
• Occurs at the ribosome

4
RNA and DNA Compared
5
Triplets (Codons)
6
Genetic Code
7
Transcription
8
Initiation

• Promoter
• TATA Box
• Initiation Site
• RNA Polymerase
• AUG

9
Elongation

• RNA Polymerase
• Adds nucleotides to the 3 end

10
Termination

• Proceeds until RNA polymerase transcribes a
  terminator sequence
• UAA
• UAG
• UGA

11
RNA Processing

• 5 guanine cap
• 3 Poly (A) tail

12
RNA Splicing

• Introns
• Exons

13
Introns????

• Regulation
• One gene can code for alternate polypeptides
• Evolution
• Domains structural and functional regions

14
Translation
15
tRNA
16
Aminoacyl-tRNA Synthetase
17
Ribosomes

• Small subunit
• Large subunit
• P site (peptidyl-tRNA)
• A site (Aminoacyl-tRNA)
• E site (Exit site)

18
Transcription
19
Initiation

• The first tRNA with its AA attaches to the mRNA
  and the small subunit
• The first tRNA and its AA enters the P site

20
Elongation

• The second tRNA and its AA enters the A site
• A peptide bond forms

21
Elongation

• Translocation
• The third tRNA and its AA enters the A site
• A peptide bond forms

22
Termination
23
Polyribosomes
24
Point Mutation
25
Point Mutation

• Base Pair Substitution

26
Frame ShiftMutation

• Base Pair Insertion or Deletion

27
(No Transcript)