While investigating the synthetic reaction of luciferin, which is deeply involved in firefly luminescence, the research group discovered that a small amount of luciferin can be produced by stirring two chemical substances with simple structures in neutral water for several hours.For the first time, it has been clarified that the complex molecules that hold the key to the luminescence reaction are assembled from substances with simple structures under the conditions that actually exist in nature.
From this, it can be predicted that about 1 million years before the appearance of the firefly ancestor, a simple luciferin reaction occurred in the body, which triggered the evolution of luminescence.Experiments on amino acid synthesis once gave great suggestions about "chemicals and evolution," but the same can be said for this discovery.

　Firefly luminescence is produced by the reaction of "luciferin" involved in the luminescence reaction of living organisms and "luciferase" that promotes the luminescence reaction.Of these, the evolutionary process of luciferase has been elucidated, leaving the elucidation of the synthetic process of luciferin.Associate Professor Oba and his colleagues had revealed that fireflies synthesize luciferin in their own bodies, but it was unclear why such a synthetic process could evolve.

　In the future, it will be an issue to elucidate the process of promoting synthetic reactions in modern fireflies.In addition, the principle of the luminescence reaction of fireflies is widely used not only in the field of basic medicine but also as a test reagent for various germs.Advances in research on this synthetic method will lead to the development of a simpler method for producing luciferin, and is expected to be applied to industry.Furthermore, the luminescence reaction of fireflies is also published in high school biology textbooks, but since this phenomenon can be reproduced in an environment such as a science room, it is considered to be useful from an educational point of view.