Biochemical Soul Musings on Nature, Science, Evolution, Biology, and Education


Evolution in Action: Fruit Flies Evolve Low Oxygen Tolerance in the Lab

Summary of alterations in signal transduction pathways.

Summary of alterations in signal transduction pathways.

ResearchBlogging.orgIn a cool new study in PLoS Genetics, through artificial selection researchers have allowed fruit flies (Drosophila) to evolve tolerance to normally lethal low levels of Oxygen.

To many scientists, this type of research will not be seen as that impressive, as a general finding. Artificial selection has been occurring for millennia, and it is the method through which we have created every domesticated animal and crop on the planet. Scientists will however find the specific genetic changes and biological pathway changes involved in this microevolution fascinating indeed. But it serves one more example (among mountains of others) of evolution being witnessed and directed under laboratory conditions.

Personally, I think one of the most amazing aspects of this study was just how quickly these flies evolved to survive and develop perpetually in severely low oxygen conditions. In only 32 generations the flies were able to live in oxygen conditions completely lethal to normal flies.

After they generated the flies, they did whole genome analyses to figure out exactly which DNA sequences and enzymatic pathways had changed in sequence or expression to result in this tolerance, including (not surprisingly) cellular respiration enzymes, citric acid cycle enzymes, and major signaling pathways, such as EGF, Insulin, Notch and Toll/Imd pathways.

Their goal is to eventually apply this information to mammalian systems to understand our own reactions to low oxygen states such as the “reduction in oxygen delivery at high altitude or during certain disease states, such as myocardial infarction and stroke.”

So yes, Sarah Palin, fruit fly research is good for something.

Dan Zhou, Jin Xue, James C. K. Lai, Nicholas J. Schork, Kevin P. White, Gabriel G. Haddad, Eric Rulifson (2008). Mechanisms Underlying Hypoxia Tolerance in Drosophila melanogaster: hairy as a Metabolic Switch PLoS Genetics, 4 (10) DOI: 10.1371/journal.pgen.1000221