Banks said understanding how the Pteris vittata functions with arsenic could lead to ways to clean up arsenic-contaminated land.
"Potentially you could take these genes and put them in any organism that could suck the arsenic out of the soil," Banks said.
Salt said rice plants could be modified with the gene to store arsenic in the roots of plants - instead of rice grains - in contaminated paddies.
Banks and Salt found another gene in Pteris vittata that looks almost exactly the same as the one that controls arsenic tolerance. When the fern was exposed to arsenic, the confirmed arsenic-tolerance gene increased its expression while the similar gene did not.
Salt said the gene that regulates arsenic tolerance could be a duplicate of the other that has changed slightly to give itself a new function.
"The fact that it has these two genes could be a sign of evolution," Salt said. "One of the thoughts of gene evolution is that one copy could continue to do what it has always done, while the duplicate can develop another function."
The plant might have evolved to accumulate arsenic, Banks and Salt theorized, as a defense against animals or insects eating them.
Banks hopes findings such as this will lead to more research emphasis on non-flowering plants. She said there are characteristics in plants such as Pteris vittata that cannot be found in other organisms.
The next step in their research is to put the arsenic-tolerance gene from Pteris vittata into Arabidopsis to see whether it gives the new plant the same characteristics.
|Contact: Brian Wallheimer|