Study: Plants use hydrogen peroxide as sunscreen

June 29 (UPI) -- Plants need sunlight to survive. But like humans, plants can suffer damage from overexposure. Plants can get sunburned, too.

New research shows hydrogen peroxide plays an important role in protecting plants from sun damage. Hydrogen peroxide, H2O2, serves as sunscreen for plants.

H2O2 is a by-product of photosynthesis. It's previously been suggested the chemical plays a sensory and signaling role, but scientists couldn't confirm where or how. The new research -- detailed in the journal Nature Communications -- shows hydrogen peroxide moves from plant cells called chloroplasts to cell nuclei, altering the response of cells to varying sunlight levels.

"It's important for plants to be able to detect how much light there is, so they can make the most of it for photosynthesis," Nick Smirnoff, researcher at the University of Exeter, said in a news release. "They also have to adjust to protect themselves, as high levels of light can damage leaves -- similar in some ways to how we humans get sunburn on our skin."

Researchers used a fluorescent protein to track the movement and behavior of H2O2 inside plant cells. The biomarker showed hydrogen peroxide moving from chloroplasts to cell nuclei where genes can be manipulated to adjust the rate of photosynthesis and ensure plant leaves don't become sunburned.

Some chloroplasts are directly connected to plant nuclei, allowing for easy movement of H2O2.

"This breakthrough was made possible by the development of the hydrogen peroxide fluorescent protein sensors, which allowed us to observe the movement of H2O2 in plant cells in real time," said Marino Exposito-Rodriguez, researcher at the University of Essex.

Because H2O2 plays a role in manipulating photosynthesis rates, the chemical could be engineered to boost crop yields.