WEST LAFAYETTE, Ind., June 10 (UPI) -- U.S. scientists say they have used genetic manipulation in research to identify a gene that allows plants to clear soil and water contaminated by arsenic.
Purdue University researchers led by Professors Jody Banks and David Salt said they isolated a gene that allows a type of fern (Pteris vittata) to tolerate up to 1,000 times more arsenic than other plants.
Without a genome sequenced for Pteris vittata, Banks and Salt used a method of gene identification called yeast functional complementation to identify the gene. They combined thousands of different Pteris vittata genes into thousands of yeast cells that were missing a gene that makes them tolerant to arsenic.
The yeast was exposed to arsenic, with most of it dying. But the yeast strains that lived had acquired the genes from the fern that convey arsenic resistance.
"It tells us this gene is necessary for the plant to function on arsenic," said Banks. "We looked for a similar gene in the plant Arabidopsis. We couldn't find it. It can't be found in any flowering plant."
Banks said understanding how the fern functions with arsenic could lead to ways to clean arsenic-contaminated land. For example, he said rice plants could be modified with the gene to store arsenic in their roots -- instead of rice grains -- in contaminated paddies.
The study appears in the early online edition of the journal Plant Cell.
