The role of GFP in recombinant DNA technology is to give researchers the ability to detect small quantities of certain proteins. By expressing them from a plasmid, they are able to use fluorescence microscopy techniques to visualize these proteins at high resolution. They also provide new opportunities for studying protein-protein interactions. The GFP gene is responsible for making green fluorescent protein. This gene was first isolated from Aequorea victoria jellyfish about 35 years ago. Nowadays, many scientists use GFP to study how individual cells behave inside living organisms. For example, biologists use GFPs to tag specific proteins inside cells, then watch how they move around and interact with other molecules.