The unexpected activity of the metabolic compound helps to decode the language of the light of the plants

The researchers have revealed a way in which plants previously unknown shape their growth in response to light – a breakthrough that could better equip crops to manage environmental stress.

In a first observation of its kind, the team discovered how a compound involved in the metabolism of plants can in fact “reprogram” an unrelated light detection protein.

This unexpected interaction, reported in the newspaper Nature communicationsis an exciting step towards a more in -depth understanding of plant physiology.

“In the future, this mechanism could be used to refine plant growth, development and stress responses,” said Erich Grotewold, professor of Michigan State University Research Foundation and author of the latest study.

“This could lead to cultures with improved tolerance for light constraint and more effective use of light energy, without based solely on environmental changes,” he added.

As much as plants need their sun, there can always be too much good. In fact, hard light can cause damage similar to a sunburn.

To protect themselves, plants produce a variety of natural “sunscreen” called flavonoids and pigments. Like similar specialized molecules that defend themselves against pests or attract pollinators, these compounds give plants an evolutionary advantage in their environment.

Originally, Grotewold and his team examined the mutant variants of the Arabidopsis model that could not produce an important flavonoid enzyme. During their experiences, the researchers noticed that a type of mutant had serious growth problems when exposed to a certain type of light, even if wild samples and other mutants seemed healthy under the same conditions.

They discovered that the culprit was a compound called Naringénine Chalcone, or NGC.

Usually, this molecule is produced as part of the metabolic process which creates flavonoids. However, because the mutant lacked a key enzyme along this path, NGC began to accumulate in the cells of the plant.

Once they knew which molecular component caused these growth faults, the team turned their attention to the larger biochemical mystery: exactly why?

By creating thousands of mutants of various arabidopsis and raising them in stressful light conditions, scientists were able to identify a handful of plants that seemed to develop without defects. The only element that these successful specimens had in common was a mutation for a specific gene called UVR8, a protein which generally detects UV light.

Thanks to a series of biochemical experiences, the Grotewold laboratory revealed that NGC interacts physically and “reprogramming” UVR8, activating it to send signals regulating growth even without the presence of UV light.

So far, such a link has not been known to be possible.

“We were surprised to discover that the Naringénine Chalone, a metabolic intermediary, could directly modulate the function of a light detection protein like UVR8,” said Nan Jiang, the main study of the study and a former Grotewold group researcher who is now a deputy professor at the University of Hawai’i in Mānoa.

“This type of diaphony between specialized metabolism and photoreceptor signaling opens up a whole new way of thinking how plants integrate metabolic status into the perception of the environment.”

In plant physiology, you could consider UVR8 as an actor in a room and NGC as a crew member behind the scenes. NGC helps keep the show smoothly, while UVR8 only meets a specific signal – a kind of particular light called UV -B.

With these results, it appeared that the crew member suddenly directed the production star.

Luckily, Grotewold did not have to look far to find out more about UVR8. Just in the corridor of the Biochemistry and Molecular Biology department of MSU, the colleague Robert Last, who earlier had isolated the protein for the very first time.

“Two decades ago, UVR8 was the last type of photoreceptor in the plants that we did not know – a photoreceptor for the Ultraviolette -B light,” said Last, a distinguished professor at the university. “Seeing this new unexpected interaction is wild and cool.”

The latest team discoveries are to reshape what we know about the complex chemical choreography that occurs between the light detection machines of a plant and its own growth.

As for the ends of this surprising molecular relationship, Grotewold sees it as a means for plants to fold more effectively the light signaling in their development.

“If you treat a plant with UV light and nothing else, it is almost deadly – but if you increase this UV intensity by a hundred times in the context of white light, the plant knows exactly how to face it,” said Grotewold. “This is what we think that NGC does, which allows to integrate light signaling into the signaling of development.”

For the future, these discoveries help extend the horizon for the modification of the plants focused on the light. By modifying the capacity of a plant to detect light and produce specific compounds, crops could be made to develop more effectively in low -light or severe environments, or better respond to harmful pathogens.

“This work reveals a new layer of regulatory complexity,” said Jiang. “This suggests that plants can use small molecules not only as final or defense compounds, but also as signaling messengers that refine key physiological responses such as growth and development.”