The jellyfish GFP is a powerful molecular tool to fluorescently label specific proteins by fusing the GFP-coding gene to the gene of interest; the dynamic behavior of these fusion proteins can be examined in living cells. In order to examine the spatial and temporal coordination of the GFP fusion protein with other intracellular structures, Haraguchi et alt. used a time-lapse multiple-wavelength fluorescence microscope system that is capable of recording simultaneously mutiple cellular components in the living state. For example, using the system, they have observed dynamic behavior of chromosomes and several GFP fusion proteins-such as lamin B receptor-GFP, cyclin B1-GFP and CENP-B-GFP-in living human cells during mitosis. This cytological technology is also applicable for visualization of mitotic and meiotic events in yeast cells. Thus, live observation of GFP fusion proteins is useful for understanding the full relevance of the temporal and spatial relationships between multiple cellular components[27].

The fusion of GFP with other proteins generates labeled proteins that can be constitutively expressed in situ for longterm studies. These chimeric proteins often maintain normal function when GFP is added to the NH2 or COOH terminus of the fusion partner. Hence, GFP is an ideal tool for labeling cellular proteins to follow their spatial and temporal localization in live-cell preparations. Illumination of living cells with light in the UV range is highly detrimental to the cells (the amount of damage is dependent on cumulative exposure time). Even with 488-nm laser line illumination of GFP there can be a disruption of normal cellular events such as mitosis. Thus, to obtain physiologically relevant data, the excitation light must be kept to an absolute minimum. The primary consideration when selecting a camera to image GFP chimeras in living cells, therefore, is sensitivity. It is important to choose a low-noise camera that maximizes signal-to-noise ratio. Additionally, to perform precise localization of the labeled structures within the cell, a medium- to high-resolution detector is preferred [28].

Here we reported same uses for GFP of particular interesting: