PROTEIN SYNTHESIS Introduction and Overview

1. PROTEIN SYNTHESIS Introduction and Overview

2. Protein Synthesis How DNA directs how proteins are made

3. The variety of life on earth is due to different proteins.

4. Protein Synthesis You are different from the people around you because your proteins are different.

5. Protein Synthesis Your hair, muscles fibres in your skin are all made of proteins.

6. Protein Synthesis If you have straight hair, your protein is slightly different to someone who has curly hair

7. Protein Synthesis • Proteins are made up of units called amino acids • In our examples we will use a few amino acids to represent a protein • Proteins are much larger and have more that 50 amino acids

8. Protein Synthesis Proteins are made up of units called amino acids. Amino acids join together to make proteins.

9. Protein Synthesis Proteins differ from each other by the type (different shapes) and sequence (the order in which the shapes occur) of amino acids. If this is the protein for straight hair A single amino acid change results in curly hair

10. Protein Synthesis The proteins are different because the DNA for curly and straight hair is different.There is a THREE letter DNA code (codon) for each amino acid.Eg. TGG codes for

11. Protein Synthesis AGC codes for aGGT codes for a In this example:TAC codes for aAAA codes for a The code for this aminoacid sequence is : What is the DNA codefor this sequence? TAC AGC GGT AAA GGT GGT

12. G A G C C C A U U A U A C T T G A C A A T A T T C G G G T A Protein Synthesis: Overview of the Process DNA RNA Protein makes makes

13. Protein Synthesis: A closer look Firstly, part of the DNA is copied into messenger RNA (mRNA)This is calledTRANSCRIPTION

14. Protein Synthesis: A closer look The mRNA carries the message to make the protein to the cytoplasm and attaches to the ribosome

15. Protein Synthesis: A closer look tRNAcollects amino acids in the cytoplasm

16. Protein Synthesis: A closer look TRANSLATION: tRNAbrings amino acids to the ribosome which link and form proteins

17. Protein Synthesis The Detailed Process

18. TRANSCRIPTION A piece of DNA that codes for a protein is copied into mRNA

19. TRANSCRIPTION Part of the DNA molecule is unzipped by an enzyme

20. TRANSCRIPTION DNA separates

21. A U G U U U U C G C C A TRANSCRIPTION T A A piece of DNA from one side is copied intomRNA C A A A A G C G G T

22. A A U G U U U U C G C C A U G G C C C U U U U A TRANSCRIPTION mRNAseparates from DNA T A C A A A A G C G G T

23. T A C A A A A U G U U U U C G C C A A G C G G T

24. T A C A A A A U G U U U U C G C C A A G C G G T mRNAmoves out of the nucleus to a ribosome in the cytoplasm ribosome

25. A A U U G G U U U U U U U U C C G G C C C C A A mRNAattaches to a ribosome

26. TRANSLATION The ribosome encodes mRNA to form a new protein

27. U A C A U G U U U U C G C C A tRNA brings a specific amino acid which links mRNA Amino Acid tRNA mRNA

28. U A C A U G U U U U C G C C A The tRNA with its specific amino links to mRNA according to its specific three letter code Amino Acid tRNA mRNA mRNA three letter code (codon) Corresponding tRNA code (anticodon)

29. U U A A C C A A A A U G U U U U C G C C A tRNA brings in the next amino acid according to the nextmRNA codon The ribosome moves along themRNA molecule exposing the next codon tRNA moves into the cytoplasm to collect another amino acid The amino acids combine

30. A A G G C C A A A A U G U U U U C G C C A tRNAs bring in another amino acids to extend the protein chain The process continues as the ribosome moves along mRNA exposing the next codon

31. A G C G G U A U G U U U U C G C C A tRNAs bring in another amino acids to extend the protein chain The process continues as the ribosome moves along mRNA exposing the next codon

32. G G U A U G U U U U C G C C A TERMINATION: Ribosome and mRNA separate NEW “Protein” is formed

33. DNA RNA A T A U C G U A A U A U A U G C G C C G G C T A Protein In Summary … makes makes