Genes As Time Machines
Scientists at the Foundation for Applied Molecular Evolution, University of Florida (both at Gainesville, FL) and DNA2.0 (Menlo Park, CA) today publish a study in the journal Nature where more than 20 ancient genes were resurrected from organisms that lived between 500 million to 3.5 billion years ago.
"By studying proteins encoded by these primordial genes, we are able to infer information about the environmental conditions of the early Earth" said Dr. Eric Gaucher at the Foundation for Applied Molecular Evolution and lead scientist of the study. "Genes evolve to adapt to the environmental conditions in which an organism lives. Resurrecting these long extinct genes gives us the opportunity to analyze and dissect the ancient surroundings that have been recorded in the gene sequence. The genes essentially behave as dynamic fossils."
The researchers chose a gene that encodes a protein which captures the environmental temperature of the gene's host organism. In essence, the resurrected genes are ancient thermometers. These 'thermometers' were used to provide evidence that the oldest bacterial life forms lived at a hot temperature of 75 degrees C ( 165 degrees F) 3.5 billion years ago, and