Discover how DNA sequences code for proteins with different roles and functions yourgenome.org

THE CODON WHEEL
- Start from the centre and move outwards
Example: CAT = H (Histidine) yourgenome.org

FUNCTION FINDERS ANSWERS
1
2
3
4
5
Amino acid sequence
M K S A I L T G L L F V
M S K G E E L F T G V V
E N M E N D E N I V Y G
G W A L R I M F L H LY
M E L A A L C R W G L L
Protein name Function
Antifreeze protein type III
Prevents fish freezing in icy seawater.
Green
Fluorescent
Protein (GFP)
Luciferase
Odorant receptor protein OR1
HER1
Used by jellyfish to communicate, also used as a marker in genetic engineering to indicate when genes have been inserted.
Used by fireflies to create light in a process called bioluminescence.
Receptor used by mosquitoes to detect the smell of sweat.
A molecular switch which turns cell division ‘on’ or ‘off’.
yourgenome.org

FUNCTION FINDERS ANSWERS
6
Amino acid sequence Protein name
P G E N L C Y R K M W C
Alphabungarotoxin
7 P R E I Q T A V R L L L Histone H2B
8
9
10
P G G E K E T S AT Q R
E K R K L F I R S M
M S S D S E M A I F
Mucin-1
Caspase 1
Myosin 1
Function
Snake venom.
Used to wind up DNA so it can be condensed into chromosomes.
Forms a protective film on the surface of cell in our bodies e.g. those lining the intestines and throat.
Destroys cellular proteins which leads to cell death (apoptosis).
Makes muscles move.
yourgenome.org

1. ANTIFREEZE PROTEIN TYPE III
Sequence M K S A I L T G L L F V
Prevents fish such as the Atlantic wolffish freezing in icy seawater.
What other organisms may use antifreeze proteins?
How can this protein be relevant to us?
DOAA, Wikimedia commons yourgenome.org

2. GREEN FLUORESCENT PROTEIN
Sequence M S K G E E L F T G V V
Used by organisms such as jellyfish
( Aequorea victoria ) to communicate.
It can also be used as a marker for successful genetic manipulation to indicate when genes have been inserted into cells.
Why is this protein relevant to us?
S. Roy, Wellcome Images yourgenome.org

3. LUCIFERASE
Sequence E N M E N D E N I V Y G
Produced by fireflies to attract a mate through a process called bioluminescence.
Which other organisms use bioluminescence?
Why is this protein relevant to us?
Antfarmer, Wikimedia commons yourgenome.org

4. ODORANT RECEPTOR PROTEIN OR1
Sequence G W A L R I M F L H L Y
Used by mosquitoes to detect human sweat.
Why is this protein relevant?
yourgenome.org

5. HER2
Sequence M E L A A L C R W G L L
Acts like a “molecular switch”, instructing cells when to divide and when not to divide.
Why is this protein relevant to us?
yourgenome.org

6. ALPHA-BUNGAROTOXIN
Sequence P G E N L C Y R K M W C
Causes muscle paralysis. This toxic snake venom is produced by the many-banded krait (Bungarus
multicinctus).
Why is this protein relevant?
Skink Chen, Flickr yourgenome.org

7. HISTONE H2B
Sequence P R E I Q T A V R L L L
Acts as a scaffold for DNA so it can be condensed into chromosomes.
Why is this protein relevant to us?
Paul Dixon yourgenome.org

8. MUCIN-1
Sequence P G G E K E T S A T Q R
Forms a protective film on the surfaces of cells in our bodies, e.g. those lining the intestines and throat.
Why is this protein relevant?
Michela Schaeppi, Wellcome Images yourgenome.org

9. CASPASE 1
Sequence E K R K L F I R S M G E
Destroys cellular proteins; this leads to cell death
(apoptosis).
Why is this protein relevant?
Paul Martin, Wellcome Images yourgenome.org

10. MYOSIN 1
Sequence M S S D S E M A I F G E
A molecular machine that makes muscle fibres contract by binding to and pulling another protein scaffold.
Why is this protein relevant to us?
Paul Foot, Wikimedia commons yourgenome.org