Professor Yuichi Oba of Chubu University, in collaboration with Nagoya University, succeeded in elucidating the origin of luciferase for the first time in fish.It was clarified that Kinmokudoki acquired an enzyme from Cypridina chinensis, which is a bait, and emits light.
Bioluminescence is a trait that is widespread from bacteria to vertebrates and has evolved many times independently throughout the history of life.The luminescence reaction is a biochemical reaction between an enzyme protein generally called "luciferase" and a chemical substance collectively called "luciferin".It is said that the luminescent organisms have evolved their own luciferases of different origins.However, there has never been a case in which the identity of luciferase has been elucidated among luminescent fish.
In this study, the amino acid sequence of the luciferase of the luminescent fish Kinmokudoki was analyzed, and it was the same as the luciferase of the crustacean Cypridina luciferase.Furthermore, it was found that when Cypridina was bred for a long period of time without feeding Cypridina, Cypridina lost its ability to emit light, and then when Cypridina was given as food, its luciferase was taken into the body and its ability to emit light was restored.
Enzymes are made of proteins, and when they enter the body as food, they are broken down in the digestive system and lose their original function.However, Kinmokudoki preyed on Cypridina and took it into cells without digesting luciferase by an unknown mechanism and used it for its original function (luminescence).
This phenomenon, which was named "theft protein" this time, is the world's first research result including all life phenomena, not limited to luminescence.It is hoped that the possibility that this phenomenon will exist universally in the biological world and its evolutionary and genetic mechanisms will be elucidated.Furthermore, various applications such as the development of oral administration methods for proteinaceous drugs are expected.
Paper information:[Science Advances] Kleptoprotein bioluminescence: Parapriacanthus fish obtain luciferase from ostracod prey