Medical Research Council - London Institute of Medical Sciences

Now in our 8th year of bringing you beautiful imagery from biomedical science every day

07 July 2013

Glowing Eels

Five years after the Nobel Prize was awarded for work on green fluorescent protein (GFP), extracted from the jellyfish Aequorea victoria, a fluorescent protein has for the first time been identified in a vertebrate. Found in the muscles of the Japanese freshwater eel (juveniles shown swimming above), it has been named UnaG, after the Japanese word for eel, unagi. The protein emits green fluorescence when it binds to bilirubin, a product of the breakdown of heme, the iron component of the blood pigment haemoglobin. UnaG could have immediate medical applications: bilirubin levels are a good indicator of liver function, so can help diagnose diseases such as jaundice, and researchers have successfully used UnaG fluorescence to monitor bilirubin in human samples. Moreover, UnaG’s vertebrate origins mean it has many different properties from the other fluorescent proteins currently known, and so should be particularly useful as a tool for future research.

Written by Emmanuelle Briolat

Search The Archive

Submit An Image

What is BPoD?

BPoD stands for Biomedical Picture of the Day. Managed by the MRC London Institute of Medical Sciences the website aims to engage everyone, young and old, in the wonders of biomedicine. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.

Read More

BPoD is also available in Catalan at with translations by the University of Valencia.