Scientists use glowing jellyfish proteins to track diseases inside human cells.

The discovery of Green Fluorescent Protein (GFP) traces back to 1962 when Osamu Shimomura isolated it from the Aequorea victoria jellyfish. This species, found in the North Pacific, uses the protein to convert blue light into a green glow. For decades, the protein remained a biological curiosity until researchers realized its potential as a molecular tag.In the 1990s, Douglas Prasher and Martin Chalfie successfully cloned the GFP gene and expressed it in other organisms like bacteria and roundworms. By fusing the GFP gene to a specific protein of interest, scientists can create a 'chimeric' protein that glows. This allows researchers to observe biological processes in living organisms without killing them or using invasive dyes.Roger Tsien further refined the technology by creating a full palette of fluorescent colors beyond green, including yellow and red. This breakthrough enabled the tracking of multiple different processes simultaneously within a single cell. Today, GFP is used to study everything from Alzheimer's disease to the way HIV buds from infected cells.The 2008 Nobel Prize in Chemistry was awarded jointly to Shimomura, Chalfie, and Tsien for their work on GFP. Their contributions transformed modern bioscience by providing a window into the microscopic world. It remains one of the most essential tools in medical research and genetic engineering today.