When intense sunlight hits a plant, it doesn't freeze up — it fights back in minutes. Scientists at Bielefeld University in Germany and the Australian National University in Canberra have discovered exactly how plants do it, and the answer could help farmers grow food in a hotter, wilder world.

The researchers found that plants can reprogram which proteins they make within just 10 minutes of facing strong light. That's lightning-fast compared to the slower process scientists used to think was the only way plants could respond — signaling to the cell's control center, called the nucleus, to switch genes on and off. That detour takes hours because genes need time to produce new messenger molecules first.

Instead, plants directly flip a molecular switch. An enzyme called GAPDH, which usually helps break down sugar, latches onto tiny sequence elements at the start of messenger RNA molecules. Depending on how bright the light is, GAPDH either attaches or detaches — turning protein production up or down like a dimmer switch. More proteins for photosynthesis get made, protecting the plant from damage.

First author Dr. Marten Moore, who started the work at Bielefeld and finished it at the Australian National University, said the team was surprised by how precisely the system works. "We were able to demonstrate that plants reprogram their protein production within minutes — well before gene activity in the cell nucleus changes," he said. "This means we have identified an additional, very rapid regulatory layer."

The researchers proved the mechanism works not just in the common lab plant Arabidopsis, but also in Setaria viridis, a type of millet. That suggests many plants — including crops — may use this same trick.

The discovery took nearly two decades to come together. Dr. Karl-Josef Dietz's research group at Bielefeld University first proposed the underlying idea about 18 years ago.

In a warming world where droughts, heat waves, and extreme sunlight are becoming more common, understanding this rapid response could matter for food security. Scientists hope to one day breed crop varieties that tap into this natural switch to grow more reliably, without having to genetically modify the plants from scratch.

"This insight opens up concrete perspectives for breeding more robust crops — a highly relevant issue in the context of climate change," Dietz said.