Environmental Physiology (FISH441) group presentation of research project

1. HYPOXIA IMPACTS ON
PACIFIC OYSTER
(CRASSOSTREA GIGAS)
GENE EXPRESSION
Abby Tillotson
Halley Nelson
Rizky Darmawan
http://osufoundation.org/news/featurednews/current/moore/index.htm

2. Hypoxia
• Dissolved oxygen CROSS Anthropogenic
concentration <2mg/l SECTION contribution
• Worldwide
• Estuaries
• Semi-enclosed seas
• Commonly seasonal
• Anthropogenic
• Increase in duration, extent Thermo- or
and magnitude Pycnocline
LOW DO
Diaz (2001); Diaz and Rosenberg (2008)

3. Dead Zone?
AQUATIC
Chronicle/Ken Stevens :Michigan Department of Natural Resources Thousands
of gizzard shad were found along the shore (Mona Lake)

4. Plasticity of Gene Expression?
HYPOXIA
http://en.wikipedia.org/wiki/File:Phenotypic_plasticity_diagram.svg

5. Secondary Ecological Impacts
• Heat-shock proteins
• Hsp70

6. Secondary Ecological Impacts
• Heat-shock proteins
• Hsp70
• Hypoxia-Inducible Factors
• HIF-1α

7. Secondary Ecological Impacts
• Heat-shock proteins
• Hsp70
• Hypoxia-Inducible Factors
• HIF-1α
• Insulin-like Growth Factor
• hrIGF-1
http://pubs.niaaa.nih.gov/publications/arh26-4/274-281.htm

8. Hypoxia Exposure
mRNA gene expression
High DO Low DO
Acclimation

9. Pacific Oyster
Why?
• Abundant
• Lives in the
intertidal zone
• Commercially
important

10. Experimental Design

11. Hsp70
1.8
1.6
1.4
mean mRNA expression of Hsp70
1.2
1
0.8
0.6
0.4
0.2
0
High DO Control Low DO
Acclimation

12. HIF-1α

13. hrIGF-1
2.5
2
Mean mRNA expression of hrIGF-1
1.5
1
0.5
0
High DO Control Low DO
Acclimation

14. Summary
1. Hsp70: General stress response, but lower levels in Low DO
acclimated group
2. HIF-1α: Lower levels in Low DO acclimated group
3. hrIGF-1: High levels in Low DO acclimated group

15. Importance
Adapt
Grow
Survive
Commercial Conservation