Live Imaging with Green Fluorescent Protein

If developmental biologists were given the chance to design the perfect cell-or tissue-specific marker, they would ensure that it had several properties. First, it would function in living animals, eliminating the need for fixation and dehydration and their associated artefacts. Second, it would permit each stage of development to be studied in a single, intact embryo. Third, it would function in all cell types and would reveal their morphology, making it simple to identify different cells without compromising their viability.