Understanding Human Genetics Disorders. Using Glowing Markers to Study Genes and Gene Expression

Jellyfish Wins Nobel Prize

Martin Chalfie, Osamu Shimomura and Rogr Y. Tsien are each several hundred thousand dollars richer thanks to their work on the glowing green fluorescent protein, GFP. It was first observed in the jellyfish, Aequorea victoria in 1962 and the award recognises the original discovery as well as many developments that have led to its use as a tagging tool in biological systems.

Human Genetic Disorders and DNA Technology

There are so many genetic disorders and important chemical processes in the body; and proteins, whether functioning or not are heavily involved. Being able to map their role in the body is key to understanding how things work and more importantly finding out why things sometimes go wrong.

By using DNA technology, GFP has become a vitally important tagging tool. For example glowing markers have revealed how cancers spread through tissues in the body, how insulin-producing beta cells are created in the pancreas of embryos as well as revealing what happens to nerve-cells in Alzheimer’s patients. Other applications include incorporating GFP in bacteria to act as environmental biosensors.

The Discovery

• Jellyfish will glow under blue or ultraviolet light because of the GFP protein. It was Shimomura who discovered this amazing property in 1962.

• It was Chalfie of Columbia University who, in the 1990’s first demonstrated GFP’s value as a tag to illuminate biological phenomena.

• Co-laureate Tsien’s work in furthering our understanding of how GFP fluoresces led to his inclusion in the award.

GFP

GFP is invaluable. It’s a tiny molecule and can be attached to almost any gene product. Then simply by shining a light on it, scientists can see where gene products are located, how the genes are being expressed as well as seeing the interactions that are taking place.

In genetic engineering it’s standard to tag the gene that codes for GFP to the genetic package that will modify a plant or animal. In this way fluorescence can tell scientists if the modification has been taken up or not.

GFP: The Molecular Spies

Roger Tsien has a neat way of summing up his life’s work. He’s professor of pharmacology, chemistry and biochemistry at UC San Diego and on his university’s website says, “Our work is often described as building and training molecular spies … molecules that will enter a cell or organism and report back to us what the conditions are, what’s going on with the biochemistry, while the cell is still alive.”

His lab uses GFP to study calcium movement in cells, which has revealed much about nerve impulses, muscle contraction and fertilisation.

The Future’s Bright

Without a shadow of a doubt, the application of GFP has revolutionised our understanding of biological systems and will continue to do so. One intriguing question still remains though. What is the purpose of GFP in jellyfish? No one really knows.