The electric eel is an amazing animal that can unleash up to 860 volts of electricity. Scientists have now found that the eel's electric current can also lead to the uptake of genetic material by fish larvae. This process is related to electroporation, a technique in which an electric field is used to create holes in cell membranes through which DNA or other molecules can move. The findings have been reported in PeerJ.
The scientists behind this work thought that electric currents in rivers could affect the cells in organisms that live in those rivers. Fragments of DNA can be found all over the environment as well, including in rivers. In the research lab, the investigators exposed very young fish to a solution that contained DNA which had been tagged with fluorescent markers. The fish larvae were then housed with an electric eel that was prompted to discharge an electric current.
The investigators found that the tagged DNA had been taken up by about five percent of the larvae, because they could see it.
Corresponding study author Professor Atsuo Iida of Nagoya University noted that electroporation was thought to be limited to the laboratory, but he had other ideas.
"I thought electroporation might happen in nature," said Iida. "I realized that electric eels in the Amazon River could well act as a power source, organisms living in the surrounding area could act as recipient cells, and environmental DNA fragments released into the water would become foreign genes, causing genetic recombination in the surrounding organisms because of electric discharge."
The presence of fluorescent DNA in the larvae shows that electric eels can power gene transfer into cells, even though they do not produce the same type of voltage as machines that are used for electroporation, added Iida.
This gene transfer may also be having some impact, the researchers suggested. "Electric eels and other organisms that generate electricity could affect genetic modification in nature."
Previous research has shown that natural sources like lightning can generate a powerful enough electric field to trigger gene transfer, which can affect organisms like soil microbes and roundworms. There could be a lot more for humans to learn about the ways of nature. "I believe that attempts to discover new biological phenomena based on such unexpected and'outside-the-box ideas will enlighten the world about the complexities of living organisms and trigger breakthroughs in the future," Iida concluded.
Sources: Nagoya University, PeerJ
