[1] A fluorescent green protein derived from this screen was serendipitously discovered to have sensitivity to ultraviolet light-- We happened to leave one of the protein aliquots on the laboratory bench overnight.
The next day, we found that the protein sample on the bench had turned red, whereas the others that were kept in a paper box remained green.
Although the sky had been partly cloudy, the red sample had been exposed to sunlight through the south-facing windows.
[1] Many PAFPs have been engineered from existing fluorescent proteins or identified from large-scale screens in the wake of Kaede's discovery.
Unlike other fluorescent proteins, PAFPs can be used as selective optical markers.