1. Protein Synthesis Making Proteins

2. DNA  Proteins  Cells  Bodies
DNA has the information to build proteins
Genes (section of DNA)
One gene codes for one protein(polypeptide)
proteins
cells
DNA gets all the glory, Proteins do all the work
bodies

3. How do proteins do all the work
proteins run living organisms
enzymes
control all chemical reactions in living organisms
structure
all living organisms are built out of proteins

4. DNA mRNA protein trait Central Dogma transcription translation nucleus
cytoplasm

5. 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
A – U
Guys!

6. Types of RNA Messenger RNA (mRNA) Ribosomal RNA (rRNA)
copy of a gene; mRNA carries the code from the nucleus to the rest of the cell
Ribosomal RNA (rRNA)
Along with certain proteins, rRNA makes up ribosomes that make proteins
Transfer RNA (tRNA)
During protein synthesis, tRNA transfers amino acids to the ribosomes

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

9. Matching 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

10. Matching 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. Matching bases of DNA & RNA
Match 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

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

13. cytoplasm
protein
nucleus
ribosome U C A G
trait

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

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

16. 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

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

18. Watch this animation to see the process in action…

19. DNA mRNA protein trait From gene to protein tRNA transcriptionaa
transcription
translation
DNA
mRNA
protein
ribosome U C A G
tRNA aa
trait
nucleus
cytoplasm

20. Transcription and Translation Review
RNA polymerase binds to DNA and separates the two strands. RNA polymerase then uses one of the strands as a template to create mRNA. (RNA polymerase binds to promoter regions on the DNA.)
Translation
Ribosomes “read” the mRNA strand. They use tRNA to build proteins from mRNA.

21. How it works mRNA contains the code, copied from DNA.
(Promoters, Start- and stop-sequences in the DNA ‘tell’ RNA polymerase where to transcribe.)
mRNA carries the code into the cytoplasm.
mRNA attaches to a ribosome.
An anticodon on a tRNA molecule binds to each codon on the mRNA.
The ribosome links the amino acids and separates them from tRNA.
Repeat 4-5 until a stop codon is reached.

22. From gene to protein
protein
transcription
translation

23. More Protein Synthesis Animations
overview
translation
overview

24. Whoops! See what happens when your genes don’t work right!
Any Questions??