1. Protein Synthesis: DNA Transcription & Translation By Jessi Jones

2. Table of Contents Slide Title Slide # What is Protein Synthesis3 The Site of Construction4 The Workers5 Transcription6 How this works7 DNA vs mRNA8 tRNA9 Codons and Their Amino Acids10 Ribosomes11 Translation12 Completion13 References14

3. What is Protein Synthesis? Protein Synthesis actually means the ‘construction’ of proteins. We need proteins for our body to grow and to work. Your body makes the proteins it needs everyday with the amino acids from the foods that you eat.

4. The Site of Construction Every cell in your body make proteins. There are 2 parts to protein synthesis; Each cell has millions of construction sites 1. Transcription: copying the plans 2. Translation: reading and constructing

5. The Workers The Nucleus the head office where all the original blue prints and important instructions are held safe as DNA. The Ribosomes the actual sites of construction, they are found throughout the cytoplasm in the cell. mRNA (messengerRNA) go into the nucleus and copy parts of the DNA and take the instructions to a ribosome. tRNA (translatorRNA) translate the instructions on the mRNA. They carry amino acids (the building blocks), and 3 codons.

6. Transcription DNA are the ‘blue prints’ for our body’s. That’s where mRNA comes in! DNA never leaves the nucleus! So, the pieces of information needed for each project has to be copied and taken to the construction sites. Messenger RNA go into the nucleus and copy the parts it needs then go out and find a ribosome.

7. How This Works 1. The DNA unwinds itself in one spot 1 2 a 2. mRNA attaches itself for a second and makes a copy of that part of the instructions. a. mRNA will replace the T codon for U b. It will also copy a start and end code. 3. When complete, the mRNA leaves the nucleus to find a ribosome. 4. The DNA strand then winds itself back up.

8. DNA vs mRNA This is a DNA double Helix. It’s called that because it is two rows twisted together. mRNA is just one row.

9. tRNA Amino acid tRNA 3 letter codon This is a tRNA ready for attachment It has an Amino Acid And the 3 letter codon

10. Codons and Their Amino Acids The 3 letter codons on tRNAs are specific to the amino acid they carry. Below is a table of the 3 letter codons and the amino acids associated with them.

11. Ribosomes During Protein Synthesis mRNA is used by many ribosomes at once. tRNA mRNA Ribosome Ribosomes are made up of 2 parts. When joined there is a small space between them where the mRNA attaches and slides through. This is also the area where the tRNAs attach and for the polypeptide chain. Space for mRNA

12. Translation 1. tRNAs 3 letter codon matches the available space on the mRNA and attaches itself. -The polypeptide is then released to coil upon itself creating a protein. - tRNA and mRNA are also released - Ribosomes break apart 2. Amino acid attaches to previous amino acid; releasing the previous tRNA continuing the polypeptide chain. 3. Repeats until end code on mRNA is reached.

13. Completion The polypeptide created coils upon itself, creating a protein. tRNAs seek specific amino acids that match its 3 letter codon. mRNAs return to the nucleus to repeat the transcription process. Ribosome’s float around the cytoplasm waiting for the next job. Protein synthesis begins again! Proteins

14. References J. Creager, J. Black, & V. Davison. 1990. Microbiology: Principles and Practice. Prentice-Hall, Inc. 839 pp. P. Raven & G. Johnson. 1999. Biology. WCB?McGraw Hill Publishing. 1284pp. W. Purves, D. Sadava, G. Orians, H. Heller. 2001. Life: The Science of Biology. WH Freeman & COmpany. 1044 pp. S. Mader. 1987. Biology: Evolution, Diversity amd the Environment. William C. Brown Publishers. 772pp.