In daylight, Neonothopanus nambi is a rather unremarkable brown fungus. But a surprise hides behind the drab façade: at night, the fungus glows ghostly green. Neonothopanus nambi is one of over 100 species of mushrooms that emit light. Aristotle already documented this phenomenon, called bioluminescence, when he described glowing, rotting treebark. Now, scientists have for the first time identified the biochemical pathway that allows bioluminescent fungi to light up. But they went even further: by putting the three genes necessary to generate luminescence into a non-glowing yeast, they created an artificially luminescent eukaryote. Fyodor Kondrashov, professor at the Institute of Science and Technology Austria (IST Austria) was co-author of the study published today in PNAS, which was led by Ilia Yampolsky at the Institute of Bioorganic Chemistry of the Russian Academy of Sciences in Moscow.