The green fluorescent protein (GFP) is a protein that exhibit bright green fluorescence when exposed to blue light. GFPSparkTM is an improved variant of the green fluorescent protein GFP. It possesses bright green fluorescence (excitation/ emission max = 487 / 508 nm) that is visible earlier than fluorescence of other green fluorescent proteins. GFPSparkTM is mainly intended for applications where fast appearance of bright fluorescence is crucial. Its amazing ability to generate a highly visible, efficiently emitting internal fluorophore is both intrinsically fascinating and tremendously valuable. It is specially recommended for cell and organelle labeling and tracking the promoter activity.