Green fluorescent protein (GFP) is a protein originally isolated from jellyfish that fluoresces when excited by either blue or ultraviolet light. This technology takes the inherent fluorescent property of GFP and combines it with genetics so that the GFP can be used as an expression reporter. The sequence for GFP is linked to the regulator element of a gene interest. Consequently, researchers can visualize the expression pattern of their gene of interest via fluorescence. Researchers have used GFP as a reporter in nearly all model organisms and its use as a gene expression marker is widely considered a “gold standard” in biological research.
Unlike other expression markers such as β-galactosidase or luciferase, GFP does not require a substrate to activate its tagging ability. Moreover, GFP is very stable and can persist even after extreme treatments such as cellular fixation. These attributes of GFP make the technology versatile for a number of applications.
Since GFP was first developed from the endogenous jellyfish gene, many modifications have been made to further expand its uses in research. Modern derivatives of the original GFP have increased stability and slightly altered fluorescence, allowing the GFP to be picked up fluorescent detectors such as flow cytometers and microscopes. Other modifications have allowed researchers to view synaptic activity in neurons, tag GFP to cell membranes, measure pH sensitivity, and tag multiple proteins using variant color mutants.
Finally, with current methods of gene modification, GFP can be delivered both in vitro and in vivo in a variety of ways.
Patent Pending WO1995007463 A1
Tech Ventures Reference: IR MS093/01/26