1. Protein Synthesis Making Proteins

2. Cell organization DNA DNA is in the nucleus
genes = instructions for making proteins
want to keep it there = protected in the nucleus
“locked in the vault”
cytoplasm
nucleus

3. Cell organization Proteins chains of amino acids
made by a “protein factory” or ribosome in cytoplasm
Rough ER protein for export, free ribosome
Protein for cell
protein factory = ribosome
cytoplasm
nucleus
build proteins
ribosome

4. Passing on DNA information
Need to get DNA gene information from nucleus to cytoplasm
need a copy of DNA
messenger RNA (mRNA) is made from DNA
mRNA can leave the nucleus
cytoplasm
nucleus
build proteins
mRNA
ribosome

6. RNA Translation: Protein Synthesis

7. From nucleus to cytoplasm
transcription
Ribosome
DNA
mRNA
protein
translation
trait
nucleus
cytoplasm

8. DNA vs. RNA DNA RNA deoxyribose sugar nitrogen bases double stranded
G, C, A, T
T : A
C : G
double stranded
RNA
ribose sugar
nitrogen bases
G, C, A, U
U : A
C : G
single stranded

9. Transcription Making mRNA from DNA
DNA strand is the template (pattern)
pairing bases
U : A
G : C
Enzyme
RNA polymerase

10. Pairing bases of DNA & RNA
Double stranded DNA unzips T G G T A C A G C T A G T C A T C G T A C C G T

11. Pairing bases of DNA & RNA
Double stranded DNA unzips T G G T A C A G C T A G T C A T C G T A C C G T

12. Pairing bases of DNA & RNA
Pair RNA bases to DNA bases on one of the DNA strands C U G A G U G U C U G C A A C U A A G C
RNA
polymerase U A G A C C T G G T A C A G C T A G T C A T C G T A C C G T

13. Pairing bases of DNA & RNA
U instead of T is matched to A
TACGCACATTTACGTACGCGG
DNA
AUGCGUGUAAAUGCAUGCGCC
mRNA
ribosome U C A G

14. cytoplasm
protein
nucleus
ribosome U C A G
trait

15. How does mRNA code for proteins
mRNA leaves nucleus
mRNA goes to ribosomes in cytoplasm
Proteins built from instructions on mRNA
mRNA U C A G aa

16. How does mRNA code for proteins?
TACGCACATTTACGTACGCGG
DNA
ribosome
AUGCGUGUAAAUGCAUGCGCC
mRNA ?
Met Arg Val Asn Ala Cys Ala
protein aa
How can you code for 20 amino acids with only 4 DNA bases (A,U,G,C)?

17. mRNA codes for proteins in triplets
TACGCACATTTACGTACGCGG
DNA
codon
ribosome
AUGCGUGUAAAUGCAUGCGCC
mRNA
AUGCGUGUAAAUGCAUGCGCC
mRNA ?
Met Arg Val Asn Ala Cys Ala
protein
Codon = block of 3 mRNA bases

18. The mRNA code For ALL life! Code has duplicates Start codon
strongest support for a common origin for all life
Code has duplicates
several codons for each amino acid
mutation insurance!
Strong evidence for a single origin in evolutionary theory.
Start codon
AUG
methionine
Stop codons
UGA, UAA, UAG

19. How are the codons matched to amino acids?
TACGCACATTTACGTACGCGG
DNA
mRNA
AUGCGUGUAAAUGCAUGCGCC
codon
UAC
Met
GCA
Arg
tRNA
CAU
Val
anti-codon
amino acid
Anti-codon = block of 3 tRNA bases

20. mRNA to protein = Translation
The working instructions  mRNA
The reader  ribosome
The transporter  transfer RNA (tRNA)
ribosome
mRNA U C A G aa
tRNA G U aa
tRNA U A C aa
tRNA G A C
tRNA aa A G U

21. From gene to RNA to protein
_____________ aa
_________________
______________
______
__________
______
ribosome U C A G
_______ aa
_____________
trait

22. From gene to RNA to proteinaa
cytoplasm
transcription
translation
DNA
mRNA
protein
ribosome U C A G
tRNA aa
trait
nucleus

23. cytoplasm
protein
transcription
translation
nucleus
trait

24. From gene to protein
protein
transcription
translation