Published 10 May 2024 by Hanna Kurlanda-Witek
A New Kind of Night Light
This year avid gardeners and plant collectors were able to purchase something completely out of the ordinary − a glowing plant. The Firefly Petunia, produced by the startup Light Bio, is the first of its kind, and despite the fact that it gives off a greenish glow in the dark, it doesn’t require any particular care and lives as long as regular petunias. The magic began in the lab by transferring four genes from bioluminescent fungi into a tobacco plant, and from there the group of plant scientists adapted the technique in a more widely-known decorative house plant.
The Science Behind the Glow
Bioluminescence is the ability of living organisms to produce light, and is a common feature in marine organisms, such as fish, jellyfish, algae and bacteria. The effect has long puzzled scientists. While aboard the Beagle, Charles Darwin observed, “(…) the sea was very luminous: light, pale, sparkling (…). The luminous particles passed through fine gauze.” Darwin also noticed that when collected in a glass, the small crustaceans glowed only while they were alive.
The mechanism that governs bioluminescence is the oxidation of the organic molecule luciferin, catalysed by enzymes such as luciferase or photoproteins. The result of this reaction is energy released in the form of light. Why would an organism go to all this trouble? There are more questions than answers, but some organisms use bioluminescence to attract prey, others to ward off predators, and still others to communicate.
The Nobel Prize for Bioluminescence
In 2008, the Nobel Prize in Chemistry was awarded to Osamu Shimomura, Martin Chalfie, and Roger Y. Tsien “for the discovery and development of the green fluorescent protein, GFP” (all three laureates gave lectures at the Lindau Nobel Laureate Meetings). Shimomura was the first to crystallise luciferin and isolate GFP from the jellyfish Aequorea victoria. Martin Chalfie transferred the GFP to other organisms, demonstrating that fluorescence can serve as a tag for biomolecules without disrupting cell processes. Roger Tsien showed that GFP could be mutated to appear brighter and not just green, but also yellow and blue. A range of colourful fluorescent proteins followed, dubbed “the fluorescent protein paintbox” by Tsien. Synthetic fluorescent molecules have vast applications, particularly in visualising biological processes through labelling—lighting up bacteria, individual cells, and tumours.
A New Trend?
The Firefly Petunia was sold out before the growing season got underway, but new plants are sure to follow (and not just petunias). Mimicking the development of GFP, there will most likely be plants that glow red, yellow, and blue. Perhaps in the coming decades gleaming flower arrangements at weddings and after-dark exhibitions at botanical gardens will become a standard feature of the horticultural world. What does this remarkable new product do for science? It isn’t a cure for infectious diseases. It won’t impact climate change. But the glow-in-the-dark plant can highlight the complexity of plant biology. It also reveals that science can simply make things pretty.