Going green – GFP antibody research

The GFP antibody targets the Green Fluorescent Protein (GFP), a highly useful protein and epitope tag derived from the bioluminescent jellyfish Aequorea Victoria, which was first cloned in 1994.GTP has proven invaluable in molecular and cell biology research, as it can demonstrate visible fluoresce in all living cells.

The protein was identified and developed by Osamu Shimomura, Martin Chalfie et al, whose contribution to the world of molecular research was recognised when they were awarded the Nobel Prize for Chemistry in 2008.GFP antibodies are widely used in epitope and protein tagging studies, with GFP being a particularly useful tool for studying gene expression.

It is highly stable and, unlike many fluorescing chemicals, not cytotoxic under excitation.The stability and reactivity of GFP is down to its unique ability to fluoresce independently of any other proteins, in its natural environment. Rather than external enzyme intervention, the chromophore is activated by three of the 238 amino acids enfolded within the GFP protein structure.

This means the GFP tag can be inserted into any living cell, from any organism, and retain full fluorescence, which can be observed and quantified via fluorescence microscopy.In genetic tagging, the GTP gene is spliced with the gene of interest, which then expresses its protein and the GTP chromophore together. The development of modified GTP proteins, excitable at different wavelengths, means several proteins can be studied together in vivo.

Where GTP expression is low, the signal can be amplified by use of a GTP antibody conjugated to a fluorescent dye such as FITC. FITC is cytotoxic, but because the conjugated GTP antibody is targeting the GTP, rather than the protein itself, this is not a problem.We at Novus Biologicals have 36 conjugated and non-conjugated GFP antibodies on our antibody database, used in a wide number of applications, including ELISA, Western blot and FRET (fluorescence energy transfer) assays.